Journal articles on the topic 'Biosensor experiments'
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Gómez-Gómez, Maribel, Ángela Ruiz-Tórtola, Daniel González-Lucas, María-José Bañuls, and Jaime García-Rupérez. "New Method for Online Regeneration of Silicon-Based Nanophotonic Biosensors." Proceedings 4, no. 1 (November 14, 2018): 22. http://dx.doi.org/10.3390/ecsa-5-05741.
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The optimal development of biosensors is a costly and time-consuming task, since an enormous amount of experiments is required. Therefore, the possibility of reusing the biosensors is highly desirable. In this work, a protocol based on the use of formamide for the regeneration of nanophotonic biosensors used for oligonucleotides detection is presented. This protocol was carried out online using the microfluidic system used to drive the target samples to the nanophotonic biosensor, thus allowing the possibility of running several experiments in a row using the same biosensor.
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Baronas, Romas, and Karolis Petrauskas. "Sudėtinės geometrinės struktūros biojutiklių kompiuterinis modeliavimas." Informacijos mokslai 56 (January 1, 2011): 156–62. http://dx.doi.org/10.15388/im.2011.0.3141.
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Biojutikliai yra analitiniai įrenginiai, skirti medžiagų koncentracijoms matuoti. Kuriant naujus biojutiklius reikia atlikti daug eksperimentų. Siekiant sumažinti atliekamų fizinių eksperimentų skaičių taikomas kompiuterinis biojutiklių veiksmo odeliavimas, kai įprastai kiekvienam struktūriškai naujam biojutikliui yra sudaromas matematinis modelis, tuomet jis keičiamas skirtuminiu, o jo lygčių sistemos sprendimas įgyvendinamas sudarant kompiuterinį modelį. Kiekvienas žingsnis reikalauja atidos ir turėtų būti automatizuotas. Straipsnyje yra pateikiamas biojutiklio metamodelis, leidžiantis formuluoti biojutiklių modelius dalykinės srities sąvokomis. Pasiūlytasis metamodelis aprašo biojutiklių modelius, formuluojamus dvimatėje erdvėje, apimančius biojutiklio struktūros, jo geometrinių savybių, biojutikliuose vykstančių reakcijų ir difuzijos procesų aprašus. Sudarius metamodelį, buvo sukurta programinė įranga, automatiškai sukonstruojanti kompiuterinį biojutiklio modelį pagal metamodeliosąvokomis išreikšto biojutiklio aprašą. Metamodelis ir programinė įranga buvo taikoma realiam biojutiklio modeliui sudaryti ir jo veiksmui modeliuoti kompiuteriniu būdu.", t. y. ištrinti žodžius "biojutiklių veiksmo.Computer-Aided Modeling of Biosensors with a Complex Geometrical StructureRomas Baronas, Karolis Petrauskas SummaryBiosensors are analytical devices used to measure the concentration of substances. When developing new biosensors, a lot of experiments are needed to be performed. Mathematical modeling of biosensors is used to decrease the number of physical experiments. Models of biosensors are usually created for each structurally unique biosensor by defining its mathematical model and the corresponding numerical approximation. Equations of the numerical model are then solved using computer programs, usually created for a particular model of the biosensor. Each of these steps requires a great attention and should be automated. The article presents a metamodel for a biosensor, enabling one to define models of biosensors in domain-specific terms. The proposed metamodel describes biosensor models, defined in the two-dimensional space and including definitions of the structure of a biosensor, its geometrical properties, reactions and diffusion processes taking place in it. Upon defining the metamodel, we compiled the computer software able to create computer models for biosensors from the models formulated according to the proposed metamodel. The metamodel was practically used to define a model for a real biosensor, and the biosensor modeling software was used to simulate its operation.
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Petrauskas, Karolis, and Romas Baronas. "Biojutiklių, modeliuojamų dvimatėje erdvėje, kompiuterinių modelių automatizuotas sudarymas." Informacijos mokslai 42, no. 43 (January 1, 2008): 108–13. http://dx.doi.org/10.15388/im.2008.0.3434.
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Biojutikliai yra plačiai naudojami tirti medžiagų koncentracijai tirpaluose. Viena pagrindinių biojutiklio sudedamųjų dalių yra fermentas. Fermentai yra gana brangios medžiagos, dėl to ir vykdyti eksperimentus yra brangu. Kuriant naujus biojutiklius tenka atlikti daug eksperimentų. Kad būtų sumažintas reikiamų eksperimentų skaičius, taikomas kompiuterinis biojutiklių veiksmo modeliavimas. Dažniausiai konkrečios geometrijos biojutikliui kuriamas konkretus jo kompiuterinis modelis. Šiame straipsnyje pristatoma sistema, kuri gali prisitaikyti prie konkrečios geometrijos biojutiklio. Sistema gali būti taikoma biojutikliams, kurių veiksmas aprašomas matematiniais modeliais, formuluojamais dvimatėje stačiakampėje srityje. Konkretaus biojutiklio matematinio modelio sprendinys komponuojamas parenkant konkrečius algoritmus.Computer aided model composition for biosensors modelled in two-dimensional spaceKarolis Petrauskas, Romas Baronas SummaryBiosensors are analytical devices that use biological components, usually enzymes, which catalyse the interaction with a target analyte. Biosensors are widely used in clinical, environment and industrial applications for the determination of species concentrations. In some applications of biosensors, enzymes are very expensive and only available in very limited quantity. In design of novel highly sensitive biosensors a lot of experiments are required. Computer simulation of the biosensor action is an effective way to decrease a number of physical experiments. This paper presents a system adaptive to a concrete geometry of the biosensor. The system may be applied for biosensors, the action of which can be described by a mathematical model formulated in a two dimensional space. A simulator for a concrete biosensor is generated from the detailed description of the biosensor action.eight: 18px;">
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Klyuchko, O. M., and P. V. Beloshitsky. "Biosensor concept and data input to biomedical infornation systems." Medical Informatics and Engineering, no. 3 (June 10, 2021): 51–69. http://dx.doi.org/10.11603/mie.1996-1960.2020.3.11698.
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Background. In present publication we generalized and analyzed deeply the experience of some biosensors studying in biophysical experiments with aim to incorporate them further to electronic information systems. Output biosensor electrical signals were input ones to electronic information system making their connection into joined bioinformation system. Materials and methods. Methods of comparative analysis of the characteristics of input and output electrical information signals of biosensor were applied; its physical and mathematical models were developed. For biosensor properties studies the methods of transmembrane electric currents recording in voltage-clamp mode as well as patch-clamp on hippocampal neuronal membranes were used. Results. Biosensor concept and their general characteristic were given, corresponding prototypes were observed. The physical model of biosensor was developed and some test results of this device were suggested. The biosensor was examined as abstraction in consistent unity of its functions: signal receiver — filter — analyzer — encoder/decoder. A brief mathematical description of biosensor functioning was given as well as corresponding algorithm. As a result of performed works the possibilities of this biosensor incorporation to bioinformation electronic systems were substantiated and the example of such system «EcoIS» was observed. Conclusion. In conclusion following results of the works were summarized. The detailed description of technical devices — biosensors as elements of biomedical information systems were done as well as analysis of electrical information signals at output of biosensor, its ability to encode information and detailed analysis of the possibility to incorporate this biotechnical device into electronic information systems due to biosensor output electricals signals.
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Uludağ, İnci, and Mustafa Kemal Sezgintürk. "Ultrasensitive and Cost-Effective Detection of Neuropeptide-Y by a Disposable Immunosensor: A New Functionalization Route for Indium-Tin Oxide Surface." Biosensors 12, no. 11 (October 26, 2022): 925. http://dx.doi.org/10.3390/bios12110925.
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Neuropeptide Y (NPY) is one of the most abundant neuropeptides in the human brain, and its levels in the blood change in neurodegenerative and neuroimmune disorders. This indicates that NPY may serve as a diagnostic and monitoring marker for associated disorders. In this paper, an electrochemical immunosensor was created to detect NPY biomarkers using a novel immobilization technique. The proposed biosensor system enables accurate, specific, cost-effective, and practical biomarker analysis. Indium tin oxide-coated polyethylene terephthalate (ITO-PET) sheets were treated with hexamethylene diisocyanate (HMDC) to covalently immobilize antibodies. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques were used to analyze each step of the biosensors. The proposed NPY biosensor has a broad linear detection range (0.01–100 pg mL−1), a low limit of detection (LOD) (0.02968 pg mL−1), and a low limit of quantification (LOQ) (0.0989 pg mL−1). Atomic force microscopy (AFM) was used to support in the optimization process, study the surface morphology, and visualize it. Studies of repeatability, reproducibility, storage, and Kramers–Kronig transformation were conducted during electrochemical characterization. After analytical experiments, the biosensor’s responses to human serum samples were evaluated. According to the obtained data, the error margin is small, and the created biosensor offers a great deal of promise for the clinical measurement of NPY.
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Skopis, Vladimir, and Igors Uteshevs. "Research in Adaptronic Automatic Control System and Biosensor System Modelling." Electrical, Control and Communication Engineering 8, no. 1 (July 1, 2015): 20–29. http://dx.doi.org/10.1515/ecce-2015-0003.
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Abstract This paper describes the research on adaptronic systems made by the author and offers to use biosensors that can be later inserted into the adaptronic systems. Adaptronic systems are based, on the one hand, on the adaptronic approach when the system is designed not to always meet the worst condition, but to change the structure of the system according to the external conditions. On the other hand, it is an extension of common automatic control ad adaptive systems. So, in the introduction firstly the adaptronic approach and biosensor as a term is explained. Adaptive systems, upon which adaptronic ones are based, are also mentioned. Then the construction of biosensor is described, as well as some information is given about the classification of biosensors and their main groups. Also it is suggested to use lichen indicators in industry to control concentration of chemical substances in the air. After that mathematical models and computer experiments for adaptronic system and biosensor analysis are given.
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Ma, Zhicong. "Effect Evaluation of Biomedical Experiment Teaching Based on Intelligent Sensor." Journal of Sensors 2022 (February 14, 2022): 1–10. http://dx.doi.org/10.1155/2022/2124462.
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With the continuous development and progress of nanotechnology, its biosensors have been widely used in biomedical experimental teaching, and good experimental results have been achieved. Graphene, as a new nanomaterial with large surface area, good thermal conductivity, and unique electrical conductivity, has unique advantages in the field of biosensor preparation. Based on this, this paper will prepare the electrochemical sensor applied to biomedical experimental teaching based on graphene, optimize the detection sensitivity and detection range of graphene electrochemical sensor based on the corresponding experimental conditions, and improve its corresponding stability and reusability. At the level of electrochemical activity of biosensors, this paper innovatively uses the electric AC impedance method to detect the electrochemical activity, so as to accurately evaluate the key characteristics of biosensors. Based on the preparation of biosensors and the results of biological experiments, this paper will design a network-based biomedical experiment teaching effect evaluation system, and realize the basic functions of teacher-student interaction, teaching effect evaluation, sensor performance evaluation and so on. Based on the above, the electrochemical sensor based on graphene and a conductive polymer solution is actually prepared in this paper. At the same time, the electrocatalysis experiment is carried out based on the sensor, and the experimental teaching effect is systematically evaluated. The experimental results show that the sensitivity of the biosensor proposed in this paper is increased by about 10% compared with the traditional biosensor, the corresponding preparation complexity is reduced by nearly 1/3, and the corresponding reusability is increased by 30%. Therefore, the biomedical experiment teaching effect evaluation system proposed in this paper has good evaluation effect. It can provide accurate reference for the evaluation of biological experiment teaching effect, so it has important value and significance.
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Antonova, Hanna, Yevgenia Babenko, Oleksandr Voronenko, Igor Galelyuka, Anna Kedych, and Oleksandra Kovyrova. "Biosensor Devices in the Production of Alcoholic and Non-Alcoholic Beverages." Cybernetics and Computer Technologies, no. 3 (September 30, 2021): 103–14. http://dx.doi.org/10.34229/2707-451x.21.3.9.
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"Smart" multisensors and biosensor systems based on modern information and communication technologies make it possible to qualitatively improve the parameters of testing systems for biologically active, chemical and toxic substances and biological or biophysical objects, improve parameter control, data processing and analysis in digital agriculture, food industry, environmental monitoring and other areas of human activity. These next-generation devices combine biologically sensitive elements with converters of biophysical signals into electrical digital signals. The article reveals the basic principles of construction of biosensor devices, their practical implementation and application. The own results of development of a wireless network of "smart" multisensors and biosensor devices for express diagnostics of a condition of grape and fruit crops and control of process of production of wine are presented. In order to test the capabilities of the unit of measurement, a number of experimental works were performed. To perform such work, it was first necessary to develop a new embedded software for the microprocessor of Analog Devices ADuCM350, and the corresponding user software for the OS Windows 10. Experiments were performed using disposable sensors based on the enzyme glucose oxidase to measure the sugar content in glucose and wine solution. A review and analysis of modern biosensor devices used in the production of alcoholic and Non-Alcoholic Beverages were done. The comparative table of analyzers for different studies based on biosensors is made. Development and preparation for mass production of "smart" biosensors, biosensor devices and networks based on them is in line with global scientific and technological trends of today and, of course, the near future. Keywords: biosensors, ammetric transducers, wireless sensor network, express diagnostics of grape and berry crops.
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RASOOLY, AVRAHAM. "Surface Plasmon Resonance Analysis of Staphylococcal Enterotoxin B in Food." Journal of Food Protection 64, no. 1 (January 1, 2001): 37–43. http://dx.doi.org/10.4315/0362-028x-64.1.37.
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Surface plasmon resonance (SPR) biosensors are electro-optical instruments used for analyzing real-time protein-protein interactions. This work evaluates an SPR biosensor (Biacore 3000) in the detection of staphylococcal enterotoxin B (SEB) in foods. A sandwich SPR immunosensor involving two antibodies was used. The capturing antibody, bound covalently to the surface of the biosensor chip, performs the initial binding of the antigen and a second antibody binds to the captured antigen. The second antibody makes antigen verification possible and amplifies the signal. Pure SEB as well as SEB in spiked foods (milk and meat) were detected with little interference from the food matrix. In the control experiments with uncontaminated food samples no significant signal was detected. The SPR biosensor assay detects SEB at ~10 ng/ml rapidly, with initial binding within 2 min. The entire measurement cycle (including washing and chip regeneration) may take 5 min using one antibody or 8 min using two antibodies. These results suggest that the SPR biosensor may be a useful tool for real-time analysis of toxin in foods.
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Klyuchko, Olena, Anatoliy Beletsky, Olga Gonchar, and Olga Melezhyk. "Bioinformation Systems with Detectors and Signal Coding Capabilities." Science and Innovation 18, no. 2 (April 30, 2022): 73–84. http://dx.doi.org/10.15407/scine18.02.073.
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Introduction. The integration of computer technologies into various fields of science allows the development of new methodologies, hybrid information systems with advanced capabilities, such as EcoIS bioinformation system for monitoring the environment with the use of biological data detectors.Problem Statement. The development of innovation bioinformation systems with biological data detectors is a very important task, as they have numerous advantages: allow rapid diagnostics and testing of chemicals in thefirst moments of their action, may be incorporated easily into electronic registration systems, may serve as elementary analytical units with data coding capabilities, etc.Purpose. The purpose of this research is to make a comprehensive analysis of different types of biological data detectors to develop a physical model of a biosensor capable of encoding signals and a bioinformation system with such detectors.Materials and Methods. The comparative analysis of information systems with functions of ecomonitoring and different types of biosensors have been used; the data are taken from electrophysiological experiments on registration of chemosensitive transmembrane electric currents in voltage clamp and patch clamp modes.Results. The physical model of biosensor has been developed and tested. The integration of the developed biosensors into the electronic bioinformation system by the example of EcoIS authors’ system has been demonstrated. Neuron-like biosensor has been considered an abstraction in the unity of its functions: signal receiver — filter — analyzer — encoder/decoder, where the input information is obtained in the form of chemical structures or electrical signals, after the conversion (recoding) of information it is registered as electrical signals with changed characteristics. The prospects for developing the cutting-edge methods for information protection in systems with biosensors have been shown. Conclusions. This development may be used for creating a bioinformation system for environmental moni toring with integrated biosensor system and data protection based on the principles and achievements of contemporary biophysics.
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Tiruthani, Karthik, Adam Mischler, Shoeb Ahmed, Jessica Mahinthakumar, Jason M. Haugh, and Balaji M. Rao. "Design and evaluation of engineered protein biosensors for live-cell imaging of EGFR phosphorylation." Science Signaling 12, no. 584 (June 4, 2019): eaap7584. http://dx.doi.org/10.1126/scisignal.aap7584.
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Live-cell fluorescence microscopy is broadly applied to study the dynamics of receptor-mediated cell signaling, but the availability of intracellular biosensors is limited. A biosensor based on the tandem SH2 domains from phospholipase C–γ1 (PLCγ1), tSH2-WT, has been used to measure phosphorylation of the epidermal growth factor receptor (EGFR). Here, we found that tSH2-WT lacked specificity for phosphorylated EGFR, consistent with the known promiscuity of SH2 domains. Further, EGF-stimulated membrane recruitment of tSH2-WT differed qualitatively from the expected kinetics of EGFR phosphorylation. Analysis of a mathematical model suggested, and experiments confirmed, that the high avidity of tSH2-WT resulted in saturation of its target and interference with EGFR endocytosis. To overcome the apparent target specificity and saturation issues, we implemented two protein engineering strategies. In the first approach, we screened a combinatorial library generated by random mutagenesis of the C-terminal SH2 domain (cSH2) of PLCγ1 and isolated a mutant form (mSH2) with enhanced specificity for phosphorylated Tyr992 (pTyr992) of EGFR. A biosensor based on mSH2 closely reported the kinetics of EGFR phosphorylation but retained cross-reactivity similar to tSH2-WT. In the second approach, we isolated a pTyr992-binding protein (SPY992) from a combinatorial library generated by mutagenesis of the Sso7d protein scaffold. Compared to tSH2-WT and mSH2, SPY992 exhibited superior performance as a specific, moderate-affinity biosensor. We extended this approach to isolate a biosensor for EGFR pTyr1148 (SPY1148). This approach of integrating theoretical considerations with protein engineering strategies can be generalized to design and evaluate suitable biosensors for various phospho-specific targets.
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Ivanov, Yuri D., Tatyana O. Pleshakova, Ivan D. Shumov, Andrey F. Kozlov, Tatyana S. Romanova, Anastasia A. Valueva, Vadim Yu Tatur, Igor N. Stepanov, and Vadim S. Ziborov. "Investigation of the Influence of Liquid Motion in a Flow-based System on an Enzyme Aggregation State with an Atomic Force Microscopy Sensor: The Effect of Water Flow." Applied Sciences 10, no. 13 (June 30, 2020): 4560. http://dx.doi.org/10.3390/app10134560.
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The influence of liquid motion in flow-based systems on the aggregation state of an enzyme and on its enzymatic activity was studied, with horseradish peroxidase (HRP) as an example. Our experiments were carried out in a setup modeling the flow section of the biosensor communication with a measuring cell containing a protein solution. Studies were conducted for a biosensor measuring cell located along the axis of a spiral-moving liquid flow. The aggregation state of the protein was determined with an atomic force microscopy-based sensor (AFM sensor). It has been demonstrated that upon flowing of water through silicone biosensor communications, an increased aggregation of HRP protein was observed, but, at the same time, its enzymatic activity did not change. Our results obtained herein are useful in the development of models describing the influence of liquid flow in biosensor communications on the properties of enzymes and other proteins. This is particularly important for the development of serologic protein biosensors, which are beginning to be used for the early diagnosis of oncological diseases (such as brain cancer, prostate cancer, breast cancer etc.). The results obtained herein should also be taken into account when considering possible changes in hemodynamics due to increased protein aggregation.
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Zarrin, Pouya, Farabi Jamal, Niels Roeckendorf, and Christian Wenger. "Development of a Portable Dielectric Biosensor for Rapid Detection of Viscosity Variations and Its In Vitro Evaluations Using Saliva Samples of COPD Patients and Healthy Control." Healthcare 7, no. 1 (January 16, 2019): 11. http://dx.doi.org/10.3390/healthcare7010011.
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Chronic Obstructive Pulmonary Disease (COPD) is a life-threatening lung disease affecting millions of people worldwide. Although the majority of patients with objective COPD go undiagnosed until the late stages of their disease, recent studies suggest that the regular screening of sputum viscosity could provide important information on the disease detection. Since the viscosity of sputum is mainly defined by its mucin–protein and water contents, dielectric biosensors can be used for detection of viscosity variations by screening changes in sputum’s contents. Therefore, the objective of this work was to develop a portable dielectric biosensor for rapid detection of viscosity changes and to evaluate its clinical performance in characterizing viscosity differences of saliva samples collected from COPD patients and Healthy Control (HC). For this purpose, a portable dielectric biosensor, capable of providing real-time measurements, was developed. The sensor performance for dielectric characterization of mediums with high water content, such as saliva, was evaluated using isopropanol–water mixtures. Subsequently, saliva samples, collected from COPD patients and HC, were investigated for clinical assessments. The radio frequency biosensor provided high repeatability of 1.1% throughout experiments. High repeatability, ease of cleaning, low-cost, and portability of the biosensor made it a suitable technology for point-of-care applications.
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ZANISHEVSKAYA, A. A., A. V. MALININ, V. V. TUCHIN, YU S. SKIBINA, and I. YU SILOKHIN. "PHOTONIC CRYSTAL WAVEGUIDE BIOSENSOR." Journal of Innovative Optical Health Sciences 06, no. 02 (April 2013): 1350008. http://dx.doi.org/10.1142/s1793545813500089.
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The hollow core photonic crystal waveguide biosensor is designed and described. The biosensor was tested in experiments for artificial sweetener identification in drinks. The photonic crystal waveguide biosensor has a high sensitivity to the optical properties of liquids filling up the hollow core. The compactness, good integration ability to different optical systems and compatibility for use in industrial settings make such biosensor very promising for various biomedical applications.
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Almadidy, Amer, James Watterson, Paul AE Piunno, Inge V. Foulds, Paul A. Horgen, and Ulrich Krull. "A fibre-optic biosensor for detection of microbial contamination." Canadian Journal of Chemistry 81, no. 5 (May 1, 2003): 339–49. http://dx.doi.org/10.1139/v03-070.
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A fibre-optic biosensor is described for detection of genomic target sequences from Escherichia coli. A small portion of the LacZ DNA sequence is the basis for selection of DNA probe molecules that are produced by automated nucleic acid synthesis on the surface of optical fibres. Fluorescent intercalating agents are used to report the presence of hybridization events with target strands. This work reviews the fundamental design criteria for development of nucleic acid biosensors and reports a preliminary exploration of the use of the biosensor for detection of sequences that mark the presence of E. coli. The research work includes consideration of the length of the strands and non-selective binding interactions that can potentially block the selective chemistry or create background signals. The biosensors were able to detect genomic targets from E. coli at a picomole level in a time of a few minutes, and dozens of cycles of use have been demonstrated. In a step towards the preparation of a completely self-contained sensor technology, a new intercalating dye known as SYBR 101 (Molecular Probes, Inc.) has been end-labelled to the LacZ nucleic acid probe, to examine whether dye tethered onto an oligonucleotide terminus could fluorimetrically transduce the formation of hybrids. The results obtained from experiments in solution indicate that the use of tethered dye provides fluorescence signals that are due to hybridization, and that this process is functional even in the presence of a high concentration of non-selective background DNA obtained from sonicated salmon sperm. Key words: biosensor, DNA, fibre optic, hybridization, fluorescence, pathogen, E. coli.
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Shokhina, AG, VV Belousov, and DS Bilan. "A genetically encoded biosensor roKate for monitoring the redox state of the glutathione pool." Laboratory diagnostics, no. 1 (March 14, 2019): 86–92. http://dx.doi.org/10.24075/brsmu.2019.013.
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Genetically encoded fluorescent sensors are exploited to study a variety of biological processes in living organisms in real time. In recent years, a whole family of biosensors has been developed, serving to visualize changes in the glutathione redox state. The aim of our experiment was to design a biosensor based on the red fluorescent protein mKate2 for measuring the 2GSH/GSSG ratio. A pair of cysteine amino acid residues were introduced into the structure of the fluorescent protein using site-directed mutagenesis. These residues form a disulfide bridge when the surrounding glutathione pool is oxidized, affecting the spectral characteristics of the protein. Our biosensor, which we called roKate, was tested in vitro on an isolated protein. Specifically, we examined the spectral characteristics, pH and the redox potential of the sensor. Additionally, the performance of roKate was evaluated using the culture of living mammalian cells. The fluorescent signal emitted by the sensor was very bright and remarkably stable under pH conditions varying in the physiological range. Irreversibly oxidized in mammalian cells, roKate stands out from other members of this biosensor family. This biosensor should be preferred in the experiments when the time between the manipulations with the biological object and the subsequent analysis of the induced effect is substantial, as is the case with long sample preparation.
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Rozman, Martin, Zala Štukovnik, Ajda Sušnik, Amirhossein Pakseresht, Matej Hočevar, Damjana Drobne, and Urban Bren. "A HepG2 Cell-Based Biosensor That Uses Stainless Steel Electrodes for Hepatotoxin Detection." Biosensors 12, no. 3 (March 4, 2022): 160. http://dx.doi.org/10.3390/bios12030160.
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Humans are frequently exposed to environmental hepatotoxins, which can lead to liver failure. Biosensors may be the best candidate for the detection of hepatotoxins because of their high sensitivity and specificity, convenience, time-saving, low cost, and extremely low detection limit. To investigate suitability of HepG2 cells for biosensor use, different methods of adhesion on stainless steel surfaces were investigated, with three groups of experiments performed in vitro. Cytotoxicity assays, which include the resazurin assay, the neutral red assay (NR), and the Coomassie Brilliant Blue (CBB) assay, were used to determine the viability of HepG2 cells exposed to various concentrations of aflatoxin B1 (AFB1) and isoniazid (INH) in parallel. The viability of the HepG2 cells on the stainless steel surface was quantitatively and qualitatively examined with different microscopy techniques. A simple cell-based electrochemical biosensor was developed by evaluating the viability of the HepG2 cells on the stainless steel surface when exposed to various concentrations of AFB1 and INH by using electrochemical impedance spectroscopy (EIS). The results showed that HepG2 cells can adhere to the metal surface and could be used as part of the biosensor to determine simple hepatotoxic samples.
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Hawkins, Elizabeth M., Ada Kanapskyte, and Sergio R. Santa Maria. "Developing Technologies for Biological Experiments in Deep Space." Proceedings 60, no. 1 (November 2, 2020): 28. http://dx.doi.org/10.3390/iecb2020-07085.
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In light of an upcoming series of missions beyond low Earth orbit (LEO) through NASA’s Artemis program and the potential establishment of bases on the Moon and Mars, the effects of the deep space environment on biology need to be examined and protective countermeasures need to be developed. Even though many biological experiments have been performed in space since the 1960s, most of them have occurred in LEO and for only short periods of time. These LEO missions have studied many biological phenomena in a variety of model organisms, as well as utilized a broad range of technologies. Given the constraints of the deep space environment, however, future deep space biological missions will be limited to microbial organisms using miniaturized technologies. Small satellites like CubeSats are capable of querying relevant space environments using novel instruments and biosensors. CubeSats also provide a low-cost alternative to more complex and larger missions, and require minimal crew support, if any. Several have been deployed in LEO, but the next iteration of biological CubeSats will go farther. BioSentinel will be the first interplanetary CubeSat and the first biological study NASA has sent beyond Earth’s magnetosphere in 50 years. BioSentinel is an autonomous free-flyer platform able to support biology and to investigate the effects of radiation on a model organism in interplanetary deep space. The BioSensor payload contained within the free-flyer is also an adaptable instrument that can perform biologically relevant measurements with different microorganisms and in multiple space environments, including the ISS, lunar gateway, and on the surface of the Moon. Nanosatellites like BioSentinel can be used to study the effects of both reduced gravity and space radiation and can house different organisms or biosensors to answer specific scientific questions. Utilizing these biosensors will allow us to better understand the effects of the space environment on biology so humanity may return safely to deep space and venture farther than ever before.
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Ullah, Sadia Fida, Geisianny Moreira, Shoumen Palit Austin Datta, Eric McLamore, and Diana Vanegas. "An Experimental Framework for Developing Point-of-Need Biosensors: Connecting Bio-Layer Interferometry and Electrochemical Impedance Spectroscopy." Biosensors 12, no. 11 (October 29, 2022): 938. http://dx.doi.org/10.3390/bios12110938.
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Biolayer interferometry (BLI) is a well-established laboratory technique for studying biomolecular interactions important for applications such as drug development. Currently, there are interesting opportunities for expanding the use of BLI in other fields, including the development of rapid diagnostic tools. To date, there are no detailed frameworks for implementing BLI in target-recognition studies that are pivotal for developing point-of-need biosensors. Here, we attempt to bridge these domains by providing a framework that connects output(s) of molecular interaction studies with key performance indicators used in the development of point-of-need biosensors. First, we briefly review the governing theory for protein-ligand interactions, and we then summarize the approach for real-time kinetic quantification using various techniques. The 2020 PRISMA guideline was used for all governing theory reviews and meta-analyses. Using the information from the meta-analysis, we introduce an experimental framework for connecting outcomes from BLI experiments (KD, kon, koff) with electrochemical (capacitive) biosensor design. As a first step in the development of a larger framework, we specifically focus on mapping BLI outcomes to five biosensor key performance indicators (sensitivity, selectivity, response time, hysteresis, operating range). The applicability of our framework was demonstrated in a study of case based on published literature related to SARS-CoV-2 spike protein to show the development of a capacitive biosensor based on truncated angiotensin-converting enzyme 2 (ACE2) as the receptor. The case study focuses on non-specific binding and selectivity as research goals. The proposed framework proved to be an important first step toward modeling/simulation efforts that map molecular interactions to sensor design.
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Sang, Sheng Bo, Wen Dong Zhang, Hui Feng, Peng Wei Li, Jie Hu, and Gang Li. "The Design of a Membrane Biosensor." Key Engineering Materials 562-565 (July 2013): 237–41. http://dx.doi.org/10.4028/www.scientific.net/kem.562-565.237.
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The need for high throughput label-free multiplexed sensors for biological sensing has increased in the last decade. In this paper, a new surface stress-based polydimethylsiloxane (PDMS) membrane biosensor for cellular detection is designed and fabricated. The geometric parameters of the PDMS membrane are optimized through the finite element (FE) analysis. One fiber optic interferometer biosensor test system is built to test the characteristics of the biosensor. The biosensor is further functionalized using 11 Mercapto 1 undecanoicacid (MUA: SH-(CH2)10-COOH) and tested in contact with cells Escherichia coli (E. coli). The results of our experiments showed that cells can be detected based on the surface stress-based PDMS membrane biosensor. The new approach for cellular detection has good sensitivity and biocompatibility.
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Delatour, Eva, Christophe Pagnout, Marie L. Zaffino, and Jérôme F. L. Duval. "Comparative Analysis of Cell Metabolic Activity Sensing by Escherichia coli rrnB P1-lux and Cd Responsive-Lux Biosensors: Time-Resolved Experiments and Mechanistic Modelling." Biosensors 12, no. 9 (September 16, 2022): 763. http://dx.doi.org/10.3390/bios12090763.
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Whole-cell bacterial sensors are used in medical/environmental applications to detect chemicals, and to assess medium toxicity or stress. Non-specific constitutive biosensors generally serve the latter purpose, whereas chemical detection is performed with biosensors involving a specific chemical-inducible promoter. Herein, we show that functioning principles of specific and non-specific whole-cell biosensors are not exclusive as both can probe modulations of cell metabolic activity under stressing conditions. The demonstration is based on (i) time-resolved measurements of bioluminescence produced by constitutive rrnB P1-luxCDABE Escherichia coli biosensor in media differing with respect to carbon source, (ii) theoretical reconstruction of the measured signals using a here-reported theory for bioluminescence generated by constitutive cells, (iii) comparison between time-dependent cell photoactivity (reflecting metabolic activity) retrieved by theory with that we reported recently for cadmium-inducible PzntA-luxCDABE E. coli in media of similar compositions. Whereas signals of constitutive and non-constitutive biosensors differ in terms of shape, amplitude and peak number depending on nutritional medium conditions, analysis highlights the features shared by their respective cell photoactivity patterns mediated by the interplay between stringent response and catabolite repressions. The work advocates for the benefits of a theoretical interpretation for the time-dependent response of biosensors to unravel metabolic and physicochemical contributions to the bioluminescence signal.
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Li, Meng, Jing Wu, Haiping Su, Yan Tu, Yazhuo Shang, Yifan He, and Honglai Liu. "Ionic Liquid-Polypyrrole-Gold Composites as Enhanced Enzyme Immobilization Platforms for Hydrogen Peroxide Sensing." Sensors 19, no. 3 (February 3, 2019): 640. http://dx.doi.org/10.3390/s19030640.
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In this work, three different aqueous solutions containing imidazole-based ILs with different alkyl chain lengths ([Cnmim]Br, n = 2, 6, 12) were adopted as the medium for the synthesis of ionic liquid-polypyrrole (IL-PPy) composites. Herein, the ILs undertook the roles of the pyrrole solvent, the media for emulsion polymerization of PPy and PPy dopants, respectively. The electrochemical performances of the three IL-PPy composites on a glassy carbon electrode (GCE) were investigated by electrochemical experiments, which indicated that [C12mim]Br-PPy (C12-PPy) composites displayed better electrochemical performance due to their larger surface area and firmer immobilization on the GCE. Further, C12-PPy/GCE were decorated with Au microparticles by electrodeposition that can not only increase the conductivity, but also immobilize sufficient biomolecules on the electrode. Then, the obtained C12-PPy-Au/GCE with outstanding electrochemical performance was employed as a horseradish peroxidase (HRP) immobilization platform to fabricate a novel C12-PPy-Au-HRP/GCE biosensor for H2O2 detection. The results showed that the prepared C12-PPy-Au-HRP/GCE biosensor exhibited high sensitivity, fast response, and a wide detection range as well as low detection limit towards H2O2. This work not only provides an outstanding biomolecule immobilization matrix for the fabrication of highly sensitive biosensors, but also advances the understanding of the roles of ILs in improving the electrochemical performance of biosensors.
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Dobrzyński, Maciej, Marc-Antoine Jacques, and Olivier Pertz. "Mining single-cell time-series datasets with Time Course Inspector." Bioinformatics 36, no. 6 (November 14, 2019): 1968–69. http://dx.doi.org/10.1093/bioinformatics/btz846.
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Abstract Summary Thanks to recent advances in live cell imaging of biosensors, microscopy experiments can generate thousands of single-cell time-series. To identify sub-populations with distinct temporal behaviours that correspond to different cell fates, we developed Time Course Inspector (TCI)—a unique tool written in R/Shiny to combine time-series analysis with clustering. With TCI it is convenient to inspect time-series, plot different data views and remove outliers. TCI facilitates interactive exploration of various hierarchical clustering and cluster validation methods. We showcase TCI by analysing a single-cell signalling time-series dataset acquired using a fluorescent biosensor. Availability and implementation https://github.com/pertzlab/shiny-timecourse-inspector. Supplementary information Supplementary data are available at Bioinformatics online.
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Bollella, Paolo, Sanjiv Sharma, Anthony E. G. Cass, Federico Tasca, and Riccarda Antiochia. "Minimally Invasive Glucose Monitoring Using a Highly Porous Gold Microneedles-Based Biosensor: Characterization and Application in Artificial Interstitial Fluid." Catalysts 9, no. 7 (June 30, 2019): 580. http://dx.doi.org/10.3390/catal9070580.
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In this paper, we present the first highly porous gold (h-PG) microneedles-based second-generation biosensor for minimally invasive monitoring of glucose in artificial interstitial fluid (ISF). A highly porous microneedles-based electrode was prepared by a simple electrochemical self-templating method that involves two steps, gold electrodeposition and hydrogen bubbling at the electrode, which were realized by applying a potential of −2 V versus a saturated calomel electrode (SCE). The highly porous gold surface of the microneedles was modified by immobilization of 6-(ferrocenyl)hexanethiol (FcSH) as a redox mediator and subsequently by immobilization of a flavin adenine dinucleotide glucose dehydrogenase (FAD-GDH) enzyme using a drop-casting method. The microneedles-based FcSH/FAD-GDH biosensor allows for the detection of glucose in artificial interstitial fluid with an extended linear range (0.1–10 mM), high sensitivity (50.86 µA cm−2 mM−1), stability (20% signal loss after 30 days), selectivity (only ascorbic acid showed a response about 10% of glucose signal), and a short response time (3 s). These properties were favourably compared to other microneedles-based glucose biosensors reported in the literature. Finally, the microneedle-arrays-based second-generation biosensor for glucose detection was tested in artificial interstitial fluid opportunely spiked with different concentrations of glucose (simulating healthy physiological conditions while fasting and after lunch) and by placing the electrode into a simulated chitosan/agarose hydrogel skin model embedded in the artificial ISF (continuous glucose monitoring). The obtained current signals had a lag-time of about 2 min compared to the experiments in solution, but they fit perfectly into the linearity range of the biosensor (0.1–10 mM). These promising results show that the proposed h-PG microneedles-based sensor could be used as a wearable, disposable, user-friendly, and automated diagnostic tool for diabetes patients.
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Stiner, Lawrence, and Larry J. Halverson. "Development and Characterization of a Green Fluorescent Protein-Based Bacterial Biosensor for Bioavailable Toluene and Related Compounds." Applied and Environmental Microbiology 68, no. 4 (April 2002): 1962–71. http://dx.doi.org/10.1128/aem.68.4.1962-1971.2002.
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ABSTRACT A green fluorescent protein-based Pseudomonas fluorescens strain A506 biosensor was constructed and characterized for its potential to measure benzene, toluene, ethylbenzene, and related compounds in aqueous solutions. The biosensor is based on a plasmid carrying the toluene-benzene utilization (tbu) pathway transcriptional activator TbuT from Ralstonia pickettii PKO1 and a transcriptional fusion of its promoter PtbuA1 with a promoterless gfp gene on a broad-host-range promoter probe vector. TbuT was not limiting, since it was constitutively expressed by being fused to the neomycin phosphotransferase (nptII) promoter. The biosensor cells were readily induced, and fluorescence emission after induction periods of 3 h correlated well with toluene, benzene, ethylbenzene, and trichloroethylene concentrations. Our experiments using flow cytometry show that intermediate levels of gfp expression in response to toluene reflect uniform induction of cells. As the toluene concentration increases, the level of gfp expression per cell increases until saturation kinetics of the TbuT-PtbuA1 system are observed. Each inducer had a unique minimum concentration that was necessary for induction, with K app values that ranged from 3.3 ± 1.8 μM for toluene to 35.6 ± 16.6 μM for trichloroethylene (means ± standard errors of the means), and maximal fluorescence response. The fluorescence response was specific for alkyl-substituted benzene derivatives and branched alkenes (di- and trichloroethylene, 2-methyl-2-butene). The biosensor responded in an additive fashion to the presence of multiple inducers and was unaffected by the presence of compounds that were not inducers, such as those present in gasoline. Flow cytometry revealed that, in response to toxic concentrations of gasoline, there was a small uninduced population and another larger fully induced population whose levels of fluorescence corresponded to the amount of effectors present in the sample. These results demonstrate the potential for green fluorescent protein-based bacterial biosensors to measure environmental contaminants.
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Sizova, Svetlana, Ruslan Shakurov, Tatiana Mitko, Fedor Shirshikov, Daria Solovyeva, Valery Konopsky, Elena Alieva, Dmitry Klinov, Julia Bespyatykh, and Dmitry Basmanov. "The Elaboration of Effective Coatings for Photonic Crystal Chips in Optical Biosensors." Polymers 14, no. 1 (December 31, 2021): 152. http://dx.doi.org/10.3390/polym14010152.
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Here, we propose and study several types of quartz surface coatings designed for the high-performance sorption of biomolecules and their subsequent detection by a photonic crystal surface mode (PC SM) biosensor. The deposition and sorption of biomolecules are revealed by analyzing changes in the propagation parameters of optical modes on the surface of a photonic crystal (PC). The method makes it possible to measure molecular and cellular affinity interactions in real time by independently recording the values of the angle of total internal reflection and the angle of excitation of the surface wave on the surface of the PC. A series of dextrans with various anchor groups (aldehyde, carboxy, epoxy) suitable for binding with bioligands have been studied. We have carried out comparative experiments with dextrans with other molecular weights. The results confirmed that dextran with a Mw of 500 kDa and anchor epoxy groups have a promising potential as a matrix for the detection of proteins in optical biosensors. The proposed approach would make it possible to enhance the sensitivity of the PC SM biosensor and also permit studying the binding process of low molecular weight molecules in real time.
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Weisenstein, Christian, Merle Richter, Anna Katharina Wigger, Anja K. Bosserhoff, and Peter Haring Bolívar. "Multifrequency Investigation of Single- and Double-Stranded DNA with Scalable Metamaterial-Based THz Biosensors." Biosensors 12, no. 7 (July 1, 2022): 483. http://dx.doi.org/10.3390/bios12070483.
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Due to the occurrence of THz-excited vibrational modes in biomacromolecules, the THz frequency range has been identified as particularly suitable for developing and applying new bioanalytical methods. We present a scalable THz metamaterial-based biosensor being utilized for the multifrequency investigation of single- and double-stranded DNA (ssDNA and dsDNA) samples. It is demonstrated that the metamaterial resonance frequency shift by the DNA’s presence depends on frequency. Our experiments with the scalable THz biosensors demonstrate a major change in the degree of the power function for dsDNA by 1.53 ± 0.06 and, in comparison, 0.34 ± 0.11 for ssDNA as a function of metamaterial resonance frequency. Thus, there is a significant advantage for dsDNA detection that can be used for increased sensitivity of biomolecular detection at higher frequencies. This work represents a first step for application-specific biosensors with potential advantages in sensitivity, specificity, and robustness.
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Pratama, Ahmad Irvan, Aisyah Sahara, and Sintia Intan Agsari. "Analysis of Blood Hemoglobin Levels Using Biosensors Based on Heme Oxygenase from Serratia marcescens." Current Biochemistry 7, no. 1 (June 1, 2020): 37–46. http://dx.doi.org/10.29244/cb.7.1.5.
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Hemoglobin levels are influenced by nutrition, iron conditions, and body metabolism. One of the medical disorders related to human blood, especially erythrocyte levels is anemia. This condition causes the need for effective and efficient methods of measuring blood hemoglobin levels, including in terms of cost. One alternative measurement of hemoglobin levels that can be used is the heme oxygenase-based sensor from Serratia marcescens. This study aims to develop techniques to measure blood hemoglobin levels by utilizing biological sensor based on heme oxygenase fromSerratia marcescens. The stages of the experiments include: rejuvenation and production of Serratia marcescens isolates, isolation of heme oxygenase, purification of enzymes with ammonium sulphate 45-65% and 65-85% saturation, measurement of protein content and enzyme activity, enzyme immobilization to the surface of carbon electrodes, and assay of biosensor heme oxygenase kinetics. Test of protein content and enzyme activity produces enzyme specific activity at 45-65% fraction of 0.0158 U/mg and at 65-85% fraction of 0.0069 U/mg, so the fraction to be used in biosensors is 45-65% fraction. The biosensor kinetics test results in a hemoglobin level of 12.0, 13.8, and 14.3 g/dL in blood samples A, B, and, C, while the hemoglobin level measured in a standard laboratory test is 12.0, 13.8, and 14.3 g/dL. It was concluded that the biosensors developed in this study can measure hemoglobin levels in blood samples with a precision of 0.8 and an accuracy of 96.04%.
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YU, FANG, and WOLFGANG KNOLL. "SURFACE PLASMON DIFFRACTION BIOSENSOR." Journal of Nonlinear Optical Physics & Materials 14, no. 02 (June 2005): 149–60. http://dx.doi.org/10.1142/s0218863505002724.
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We describe experiments with surface plasmon polaritons excited by a laser beam in the Kretschmann configuration that are diffracted by a periodic pattern at the metal/dielectric interface. This suggested technique has become a novel sensing principle with particular potential for bio-affinity studies. It is demonstrated that the optical field enhancements associated with the resonant excitation of surface plasmons directly translate into a sensitivity gain. A few characteristic features of the obtained diffraction patterns, e.g., the quadratic increase of the intensity diffracted into higher order spots with the increase of the grating amplitude, are discussed. Moreover, it is shown that the basic mechanism of the signal generation leads to a so-called self-referencing of the sensor which makes it largely insensitive to variations in temperature or refractive index fluctuations of the analyte solution.
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Lee, Taek, Jinmyeong Kim, Inho Nam, Yeonju Lee, Ha Eun Kim, Hiesang Sohn, Seong-Eun Kim, et al. "Fabrication of Troponin I Biosensor Composed of Multi-Functional DNA Structure/Au Nanocrystal Using Electrochemical and Localized Surface Plasmon Resonance Dual-Detection Method." Nanomaterials 9, no. 7 (July 11, 2019): 1000. http://dx.doi.org/10.3390/nano9071000.
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In the present study, we fabricated a dual-mode cardiac troponin I (cTnI) biosensor comprised of multi-functional DNA (MF-DNA) on Au nanocrystal (AuNC) using an electrochemical method (EC) and a localized surface plasmon resonance (LSPR) method. To construct a cTnI bioprobe, a DNA 3 way-junction (3WJ) was prepared to introduce multi-functionality. Each DNA 3WJ arm was modified to possess a recognition region (Troponin I detection aptamer), an EC-LSPR signal generation region (methylene blue: MB), and an anchoring region (Thiol group), respectively. After an annealing step, the multi-functional DNA 3WJ was assembled, and its configuration was confirmed by Native-TBM PAGE for subsequent use in biosensor construction. cTnI was also expressed and purified for use in biosensor experiments. To construct an EC-LSPR dual-mode biosensor, AuNCs were prepared on an indium-tin-oxide (ITO) substrate using an electrodeposition method. The prepared multi-functional (MF)-DNA was then immobilized onto AuNCs by covalent bonding. Field emission scanning electron microscope (FE-SEM) and atomic force microscopy (AFM) were used to analyze the surface morphology. LSPR and electrochemical impedance spectroscopy (EIS) experiments were performed to confirm the binding between the target and the bioprobe. The results indicated that cTnI could be effectively detected in the buffer solution and in diluted-human serum. Based on the results of these experiments, the loss on drying (LOD) was determined to be 1.0 pM in HEPES solution and 1.0 pM in 10% diluted human serum. Additionally, the selectivity assay was successfully tested using a number of different proteins. Taken together, the results of our study indicate that the proposed dual-mode biosensor is applicable for use in field-ready cTnI diagnosis systems for emergency situations.
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Centonze, Diego, Carlo G. Zambonin, and Francesco Palmisano. "Determination of Glucose in Nonalcoholic Beverages by a Biosensor Coupled with Microdialysis Fiber Samplers." Journal of AOAC INTERNATIONAL 80, no. 4 (July 1, 1997): 829–33. http://dx.doi.org/10.1093/jaoac/80.4.829.
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Abstract Glucose in soft drinks, fruit juices, and milk was determined by an interference-free amperometric biosensor coupled with microdialysis fiber samplers. The biosensor was based on glucose oxidase (GOx) immobilized on a platinum electrode by an electroproduced bilayer of overoxidized polypyrrole (Pt/PPyox,GOx/PPyox). The first undercoating of PPyox entrapped GOx, and the second, grown onto the first, limited glucose diffusion, hence improving linearity of response. Such a biosensor coupled with microdialysis sampling extended the linear range to 500 mM. The biosensor response was not affected by sample pH variations in the range 2–10. The influence of flow rate on biosensor response was also investigated. The glucose response of the device in both continuous and discontinuous flow injection experiments showed good repeatability and sensitivity. Real samples containing high glucose concentrations were easily analyzed without pretreatment such as dilution or filtration. Results were in good agreement with those of the reference method.
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Centonze, Diego, Carlo G. Zambonin, and Francesco Palmisano. "Determination of Glucose in Nonalcoholic Beverages by a Biosensor Coupled with Microdialysis Fiber Samplers." Journal of AOAC INTERNATIONAL 80, no. 4 (July 1, 1997): 829–44. http://dx.doi.org/10.1093/jaoac/80.4.834.
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Abstract Glucose in soft drinks, fruit juices, and milk was determined by an interference-free amperometric biosensor coupled with microdialysis fiber samplers. The biosensor was based on glucose oxidase (GOx) immobilized on a platinum electrode by an electroproduced bilayer of overoxidized polypyrrole (Pt/PPyox,GOx/PPyox). The first undercoating of PPyox entrapped GOx, and the second, grown onto the first, limited glucose diffusion, hence improving linearity of response. Such a biosensor coupled with microdialysis sampling extended the linear range to 500 mM. The biosensor response was not affected by sample pH variations in the range 2–10. The influence of flow rate on biosensor response was also investigated. The glucose response of the device in both continuous and discontinuous flow injection experiments showed good repeatability and sensitivity. Real samples containing high glucose concentrations were easily analyzed without pretreatment such as dilution or filtration. Results were in good agreement with those of the reference method.
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Huang, Gang, Yu Xin Li, Li Qian, and Qi Li. "Fabrication of a Pendulous Resonant Micro-Machined Biosensor for Direct Liquid Detection." Key Engineering Materials 645-646 (May 2015): 1267–72. http://dx.doi.org/10.4028/www.scientific.net/kem.645-646.1267.
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This paper presents a pendulous resonant MEMS biosensor for liquid detection based on SOI-MEMS technology. The biosensor consists of two electromagnetically driven and sensed resonant paddles working in the torsional mode. The differential output consisted by the two paddles provides the sensor reading. 1um thick SiNx is deposited on the electrodes by plasma enhanced chemical vapor deposition (PECVD), making the biosensor capable of working in liquid directly. In device fabrication, SOI-MEMS fabrication processes were utilized, where a new modified buffered hydrofluoric acid (BHF) solution was used to remove the buried oxide layer and release the paddles. High-current drive circuit and energy compensation circuit are designed to improve the Q-factor of the paddle in liquid. Experimental experiments show that the biosensor can distinguish the density of some liquid effectively．
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Wondimu, Sentayehu F., Sebastian von der Ecken, Ralf Ahrens, Wolfgang Freude, Andreas E. Guber, and Christian Koos. "Integration of digital microfluidics with whispering-gallery mode sensors for label-free detection of biomolecules." Lab on a Chip 17, no. 10 (2017): 1740–48. http://dx.doi.org/10.1039/c6lc01556e.
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Akcakoca, Iremnur, Hamed Ghorbanpoor, Ewen Blair, Yasin Ozturk, Araz Norouz Dizaji, Tanil Kocagoz, Huseyin Avci, Damion Corrigan, and Fatma Dogan Guzel. "An electrochemical biosensor with integrated microheater to improve the sensitivity of electrochemical nucleic acid biosensors." Journal of Micromechanics and Microengineering 32, no. 4 (March 15, 2022): 045008. http://dx.doi.org/10.1088/1361-6439/ac5a62.
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Abstract Electrochemical impedance spectroscopy is often used for biomolecular detection based on the interaction of a molecule with a receptor functionalised electrode surface and consequent impedance change. Though its performance is well established, there is still a need for improved sensitivity and specificity, especially when attempting to detect nucleic acids from clinical samples with minimal amplification steps. Localised heating is a potential approach for improving nucleic hybridisation rates and reducing non-specific interactions, and thereby producing high sensitivity and selectivity. The aim of the study was therefore to develop a microheater surrounding Au thin film electrodes, an integrated hybrid chip, for detecting genes of Mycobacterium tuberculosis with enhanced sensitivity. The performance of the integrated hybrid chip was determined using the changes in the charge transfer resistance (R ct) upon DNA hybridisation using probe sequences for M. tuberculosis. Heat transfer within the system was simulated by using COMSOL Multiphysics as a mathematical modelling tool. When a temperature of 50 °C was applied to the microheater during DNA hybridisation steps, R ct values (which were indicative of DNA–DNA hybridisation) increased 236% and 90% as opposed to off-chip non-heated experiments and off-chip heated experiments. It is concluded from these observations that the microheater indeed can significantly improve the performance of the nucleic acid hybridisation assay and paves the way for the development of highly sensitive and specific integrated label-free biosensors.
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You, Zhu-Hong, Shuai Li, Xin Gao, Xin Luo, and Zhen Ji. "Large-Scale Protein-Protein Interactions Detection by Integrating Big Biosensing Data with Computational Model." BioMed Research International 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/598129.
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Protein-protein interactions are the basis of biological functions, and studying these interactions on a molecular level is of crucial importance for understanding the functionality of a living cell. During the past decade, biosensors have emerged as an important tool for the high-throughput identification of proteins and their interactions. However, the high-throughput experimental methods for identifying PPIs are both time-consuming and expensive. On the other hand, high-throughput PPI data are often associated with high false-positive and high false-negative rates. Targeting at these problems, we propose a method for PPI detection by integrating biosensor-based PPI data with a novel computational model. This method was developed based on the algorithm of extreme learning machine combined with a novel representation of protein sequence descriptor. When performed on the large-scale human protein interaction dataset, the proposed method achieved 84.8% prediction accuracy with 84.08% sensitivity at the specificity of 85.53%. We conducted more extensive experiments to compare the proposed method with the state-of-the-art techniques, support vector machine. The achieved results demonstrate that our approach is very promising for detecting new PPIs, and it can be a helpful supplement for biosensor-based PPI data detection.
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Yoshimine, Hiroshi, Kai Sasaki, and Hiroyuki Furusawa. "Pocketable Biosensor Based on Quartz-Crystal Microbalance and Its Application to DNA Detection." Sensors 23, no. 1 (December 27, 2022): 281. http://dx.doi.org/10.3390/s23010281.
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Quartz-crystal microbalance (QCM) is a technique that can measure nanogram-order masses. When a receptor is immobilized on the sensor surface of a QCM device, the device can detect chemical molecules captured by the mass change. Although QCM devices have been applied to biosensors that detect biomolecules without labels for biomolecular interaction analysis, most highly sensitive QCM devices are benchtop devices. We considered the fabrication of an IC card-sized QCM device that is both portable and battery-powered. Its miniaturization was achieved by repurposing electronic components and film batteries from smartphones and wearable devices. To demonstrate the applicability of the card-sized QCM device as a biosensor, DNA-detection experiments were performed. The card-sized QCM device could detect specific 10-mer DNA chains while discerning single-base differences with a sensitivity similar to that of a conventional benchtop device. The card-sized QCM device can be used in laboratories and in various other fields as a mass sensor.
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Zhu, Jieyi, Meiyan Feng, and Guofu Lian. "Graphene Based FET Biosensor for Organic-Phosphorous Sample Detection and the Enzymatic Analysis." Crystals 12, no. 10 (September 20, 2022): 1327. http://dx.doi.org/10.3390/cryst12101327.
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Our paper presents a flexible enzymatic acetylcholinesterase graphene based FET biosensor of the target organic phosphorous. The sensor’s purpose is to detect pesticide residues in the field of food safety. In our sensor design, the material is graphene with its functionalization, and graphene based FET structure will be discussed in one section of this paper. The mechanism of this graphene sensor is the enzymatic linked reaction on a sensor surface. The enzyme is fixed on the sensor surface by the linker 3-mercapto propionic acid. Measurement experiments using the biosensor were performed for detecting the concentration of isocarbophos (an organophosphate). The enzymatic biosensor has successfully detected 100 μg/mL isocarbophos from the water sample, presenting a significant detection limit index for organophosphate detection.
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Hirata, Eishu, and Etsuko Kiyokawa. "ERK Activity Imaging During Migration of Living Cells In Vitro and In Vivo." International Journal of Molecular Sciences 20, no. 3 (February 5, 2019): 679. http://dx.doi.org/10.3390/ijms20030679.
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Extracellular signal-regulated kinase (ERK) is a major downstream factor of the EGFR-RAS-RAF signalling pathway, and thus the role of ERK in cell growth has been widely examined. The development of biosensors based on fluorescent proteins has enabled us to measure ERK activities in living cells, both after growth factor stimulation and in its absence. Long-term imaging unexpectedly revealed the oscillative activation of ERK in an epithelial sheet or a cyst in vitro. Studies using transgenic mice expressing the ERK biosensor have revealed inhomogeneous ERK activities among various cell species. In vivo Förster (or fluorescence) resonance energy transfer (FRET) imaging shed light on a novel role of ERK in cell migration. Neutrophils and epithelial cells in various organs such as intestine, skin, lung and bladder showed spatio-temporally different cell dynamics and ERK activities. Experiments using inhibitors confirmed that ERK activities are required for various pathological responses, including epithelial repair after injuries, inflammation, and niche formation of cancer metastasis. In conclusion, biosensors for ERK will be powerful and valuable tools to investigate the roles of ERK in situ.
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Ye, Weiwei, Yu Zhang, Wei Hu, Liwen Wang, Yu Zhang, and Ping Wang. "A Sensitive FRET Biosensor Based on Carbon Dots-Modified Nanoporous Membrane for 8-hydroxy-2′-Deoxyguanosine (8-OHdG) Detection with Au@ZIF-8 Nanoparticles as Signal Quenchers." Nanomaterials 10, no. 10 (October 16, 2020): 2044. http://dx.doi.org/10.3390/nano10102044.
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A sensitive fluorescence resonance energy transfer (FRET) biosensor is proposed to detect 8-hydroxy-2′-deoxyguanosine (8-OHdG), which is a typical DNA oxidation damage product excreted in human urine. The FRET biosensor was based on carbon dots (CDs)-modified nanoporous alumina membrane with CDs as fluorescence donors. Gold nanoparticles were encapsulated in zeolitic imidazolate framework-8 to form Au@ZIF-8 nanoparticles as signal quenchers. CDs and Au@ZIF-8 nanoparticles were biofunctionalized by 8-OHdG antibody. The capture of 8-OHdG on the membrane substrates can bring Au@ZIF-8 nanoparticles closely to CDs. With 350 nm excitation, the fluorescence of CDs was quenched by Au@ZIF-8 nanoparticles and FRET effect occurred. The quenching efficiency was analyzed. The limit of detection (LOD) was 0.31 nM. Interference experiments of the FRET biosensor showed good specificity for 8-OHdG detection. The biosensor could detect urinary 8-OHdG sensitively and selectively with simple sample pretreatment processes. It shows applicability for detecting biomarkers of DNA damage in urine or other biological fluids.
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Xiong, Nian, Tian Guan, Yang Xu, Lixuan Shi, Suyi Zhong, Xuesi Zhou, Yonghong He, and Dongmei Li. "A Differential Detection Method Based on a Linear Weak Measurement System." Sensors 19, no. 11 (May 30, 2019): 2473. http://dx.doi.org/10.3390/s19112473.
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Self-reference detection is necessary and important to a biosensor. The linear weak measurement system based on total internal reflection has attracted widespread attention due to its high stability, label-free detection, and easy integration. In this paper, we propose a differential detection method based on the linear total internal reflection weak measurement system. We introduce the half-wave plate (HWP) to convert the H light and the V light to each other, thereby obtaining the difference in phase change of the optical path before and after the HWP. Experiments show that the system can not only achieve differential detection, but also has high stability. The linear differential weak measurement system proposed in this paper not only provides a new differential measurement method for real-time biosensors, but also enriches the types of weak measurement sensors.
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WHYTE, JASON M. "GLOBAL A PRIORI IDENTIFIABILITY OF MODELS OF FLOW-CELL OPTICAL BIOSENSOR EXPERIMENTS." Bulletin of the Australian Mathematical Society 98, no. 2 (June 14, 2018): 350–52. http://dx.doi.org/10.1017/s0004972718000357.
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He, Fan, Yudong Shen, and Juewen Liu. "SYBR Green I promotes melamine binding to poly-thymine DNA and FRET-based ratiometric sensing." Analyst 146, no. 5 (2021): 1642–49. http://dx.doi.org/10.1039/d1an00102g.
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Using SYBR Green I for DNA melting experiments, polythymine DNA binding to melamine was found to be an intramolecular reaction, allowing the design of a FRET-based biosensor and its sensitivity was enhanced by SYBR Green I.
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Mitko, Tatiana V., Ruslan I. Shakurov, Fedor V. Shirshikov, Sizova V. Svetlana, Elena V. Alieva, Valery N. Konopsky, Dmitry V. Basmanov, and Julia A. Bespyatykh. "Development of a microfluidic biosensor for the diagnostics and typing of Mycobacterium Tuberculosis." Journal of Clinical Practice 12, no. 2 (July 23, 2021): 14–20. http://dx.doi.org/10.17816/clinpract71815.
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Background. Despite on the general trend towards decreasing the incidence of newly diagnosed active forms of tuberculosis, the situation with spreading of this disease in Russian Federation remains extremely tense. At the same time, the diagnosis is carried out according to the standard scheme, which takes about a month; another month takes test formulation for drug sensitivity. Thus, the development of new methods for diagnostics and typing of mycobacteria, as well as practice implementation of these developments is an urgent direction. Modern developments in the field of microfluidic technologies open up great opportunities in this direction. Aim. Development of a method for identification and typing of Mycobacterium tuberculosis using a label-free biosensor on surface waves in a one-dimensional photonic crystal (PC SM biosensor). Methods. Oligonucleotide probes were selected and synthesized as DNA targets for M. tuberculosis typing. The photonic crystal surface was modified with aqueous solutions of (3-aminopropyl)triethoxysilane, Leuconostoc mesenteroides dextrans and bovine serum albumin. Experiments were carried out using a PC SM biosensor. Results. Sequences of detecting oligonucleotide probes were selected for spoligotyping of M. tuberculosis on the PC SM biosensor. Modification of their 3'-ends was carried out in order to create extended single-stranded regions that are not subject to the formation of secondary structures and facilitate hybridization with a single-stranded DNA target. Several series of experimental modifications of the PC surface were carried out by using L. mesenteroides dextrans with different functional groups (including detection of the modification results real time) with simultaneous registration of the increment layer size and volume refractive index of the mixture, which excludes the use of a reference cell. Other experiments were carried out to detect the specific binding of biotinylated oligonucleotide probes to the modified PC surface. Conclusions. A technique for the design of probes was developed and a model system of oligonucleotides for the detection of single-stranded DNA using a PC biosensor was proposed. The developed technique of modification of the PC surface with dextrans from L. mesenteroides, which allows to increase the sensitivity of detection of oligonucleotides using the PC SM biosensor. This approach will further expand the panel of diagnostic probes, including identification of resistance markers.
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Reddy, Gopireddy Raghavender, Toni M. West, Zhong Jian, Mark Jaradeh, Qian Shi, Ying Wang, Ye Chen-Izu, and Yang K. Xiang. "Illuminating cell signaling with genetically encoded FRET biosensors in adult mouse cardiomyocytes." Journal of General Physiology 150, no. 11 (September 21, 2018): 1567–82. http://dx.doi.org/10.1085/jgp.201812119.
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FRET-based biosensor experiments in adult cardiomyocytes are a powerful way of dissecting the spatiotemporal dynamics of the complicated signaling networks that regulate cardiac health and disease. However, although much information has been gleaned from FRET studies on cardiomyocytes from larger species, experiments on adult cardiomyocytes from mice have been difficult at best. Thus the large variety of genetic mouse models cannot be easily used for this type of study. Here we develop cell culture conditions for adult mouse cardiomyocytes that permit robust expression of adenoviral FRET biosensors and reproducible FRET experimentation. We find that addition of 6.25 µM blebbistatin or 20 µM (S)-nitro-blebbistatin to a minimal essential medium containing 10 mM HEPES and 0.2% BSA maintains morphology of cardiomyocytes from physiological, pathological, and transgenic mouse models for up to 50 h after adenoviral infection. This provides a 10–15-h time window to perform reproducible FRET readings using a variety of CFP/YFP sensors between 30 and 50 h postinfection. The culture is applicable to cardiomyocytes isolated from transgenic mouse models as well as models with cardiac diseases. Therefore, this study helps scientists to disentangle complicated signaling networks important in health and disease of cardiomyocytes.
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Chen, Yan, Wenpeng Liu, Hao Zhang, Daihua Zhang, and Xiaoliang Guo. "A Sensitivity-Enhanced Electrolyte-Gated Graphene Field-Effect Transistor Biosensor by Acoustic Tweezers." Micromachines 12, no. 10 (October 13, 2021): 1238. http://dx.doi.org/10.3390/mi12101238.
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Low-abundance biomolecule detection is very crucial in many biological and medical applications. In this paper, we present a novel electrolyte-gated graphene field-effect transistor (EGFET) biosensor consisting of acoustic tweezers to increase the sensitivity. The acoustic tweezers are based on a high-frequency bulk acoustic resonator with thousands of MHz, which has excellent ability to concentrate nanoparticles. The operating principle of the acoustic tweezers to concentrate biomolecules is analyzed and verified by experiments. After the actuation of acoustic tweezers for 10 min, the IgG molecules are accumulated onto the graphene. The sensitivities of the EGFET biosensor with accumulation and without accumulation are compared. As a result, the sensitivity of the graphene-based biosensor is remarkably increased using SMR as the biomolecule concentrator. Since the device has advantages such as miniaturized size, low reagent consumption, high sensitivity, and rapid detection, we expect it to be readily applied to many biological and medical applications.
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Buhl, Alexander, Jochen H. Metzger, Niels H. H. Heegaard, Philipp von Landenberg, Martin Fleck, and Peter B. Luppa. "Novel Biosensor–Based Analytic Device for the Detection of Anti–Double-Stranded DNA Antibodies." Clinical Chemistry 53, no. 2 (February 1, 2007): 334–41. http://dx.doi.org/10.1373/clinchem.2006.077339.
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Abstract Background: Patients with systemic lupus erythematosus (SLE) develop a wide variety of serologic manifestations, including double-stranded DNA autoantibodies (anti-dsDNA). The determination of the potentially pathogenic autoantibodies is diagnostically relevant. Methods: We developed a novel surface plasmon resonance (SPR) biosensor chip for studies of dsDNA and anti-dsDNA binding. A synthetic oligonucleotide was coupled to biotinylated human transferrin, hybridized with the complementary antistrand, and ligated with a human recombinant dsDNA fragment 233 bp in length. After surface immobilization of this antigenic construct, diluted sera from SLE patients and healthy donors were analyzed with the resulting SPR biosensor system. Results: This SPR biosensor allowed specific detection of anti-dsDNA. In pilot experiments, sera from SLE patients were distinguished from control sera. We also confirmed the specificity of this biosensor by supplementing anti-dsDNA–positive sera with salmon sperm DNA, which blocked the surface binding of anti-dsDNA in a concentration-dependent manner. Conclusions: An SPR biosensor monitors interactions in real time under homogeneous conditions, providing information about binding kinetics and affinities. Its applicability critically depends on the design of the solid-state surface of the sensor chips. Covalently immobilizing dsDNA as the antigen to the surface in a flow-through cell assured maximal stability for multiple serum injections and regeneration cycles. This technique, which adds a new analytic quality to existing methods, may be beneficial in the diagnosis and clinical monitoring of SLE.
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Liang, Aoming, Yafang Shen, Yawen He, Jianping Wang, and Yanbin Li. "An Automated Magnetic Separation Device Coupled with a Fluorescent Biosensor for Detection of Antibiotic Residues." Transactions of the ASABE 64, no. 1 (2021): 23–30. http://dx.doi.org/10.13031/trans.14076.
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HighlightsA practical magnetic separation device was designed, fabricated, and evaluated for enrofloxacin detection.Coupled with a fluorescent biosensor, the device could automatically process a sample in 50 min.The device performed incubation and magnetic separation using a pipette method.The device has the advantages of low-cost and feasibility for on-site detection.Abstract. Antibiotic residues have been a continuing concern in food safety, raising a great issue in human health. For rapid detection of antibiotics, an automated device was developed that can capture and separate a target analyte based on immunomagnetic beads. This automated separation device is suitable for separating the magnetic beads in a preprocessing step, with liquid transfer and magnetic enrichment functions. The device was combined with a fluorescent biosensor to simplify the cumbersome pretreatment of enrofloxacin. In our experiments, enrofloxacin in water samples was used as the detection object, and the entire process could be completed in less than 50 min with automated operation. The lower limit of detection reached 54 ng mL-1 (S/N = 3). The fluorescent biosensor has been enhanced with this automated separation device for more sensitive rapid detection of antibiotic residues in the food supply chain and environment. Keywords: Antibiotic detection, Automation, Fluorescent biosensor, Immunomagnetic separation, Sample pretreatment.
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Xinyu, Bian, Fan Sun, and Zhixuan Xu. "How Protein Labeling Applying." E3S Web of Conferences 290 (2021): 01020. http://dx.doi.org/10.1051/e3sconf/202129001020.
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In recent years, biosensing has played an irreplaceable position in scientific fields as well as our daily lives. A biosensor is an instrument that is sensitive to biological substances and converts its concentration into electrical signals for detection. It is an analysis tool or system composed of immobilized biologically sensitive materials as identification elements, appropriate physical and chemical transducers and signal amplification devices, and it has the functions of both a receiver and a converter. Pregnancy test sticks, blood glucose testing, etc. in life are all potential biosensors. The main point of this paper is to introduce several main techniques of biosensing for better understanding, like ELISA, fusion proteins, fluorescent probe and others. In the future, the bright future for them is also worth looking forward to if more researches and experiments can be processed in this area, for example, in the detection and treatment of cancer, medical technology can be further improved.
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Jenison, Robert, Helen La, Ayla Haeberli, Rachel Ostroff, and Barry Polisky. "Silicon-based Biosensors for Rapid Detection of Protein or Nucleic Acid Targets." Clinical Chemistry 47, no. 10 (October 1, 2001): 1894–900. http://dx.doi.org/10.1093/clinchem/47.10.1894.
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Abstract Background: We developed a silicon-based biosensor that generates visual, qualitative results or quantitative results for the detection of protein or nucleic acid targets in a multiplex format. Methods: Capture probes were immobilized either passively or covalently on the optically coated surface of the biosensor. Intermolecular interactions of the immobilized capture probe with specific target molecules were transduced into a molecular thin film. Thin films were generated by enzyme-catalyzed deposition in the vicinity of the surface-bound target. The increased thickness on the surface changed the apparent color of the biosensor by altering the interference pattern of reflected light. Results: Cytokine detection was achieved in a 40-min multiplex assay. Detection limits were 4 ng/L for interleukin (IL)-6, 31 ng/L for IL1-β, and 437 ng/L for interferon-γ. In multianalyte experiments, cytokines were specifically detected with signal-to-noise ratios ranging from 15 to 80. With a modified optical surface, specificity was also demonstrated in a nucleic acid array with unambiguous discrimination of single-base changes in a 15-min assay. For homozygous wild-type and homozygous mutant samples, signal-to-noise ratios of ∼100 were observed. Heterozygous samples yielded approximately equivalent signals for wild-type and mutant capture probes. Conclusions: The thin-film biosensor allows rapid, sensitive, and specific detection of protein or nucleic acid targets in an array format with results read visually or quantified with a charge-coupled device camera. This biosensor is suited for multianalyte detection in clinical diagnostic assays.