Journal articles: 'Microsensor'

1

Hashim, Hairulazwan, Hisataka Maruyama, Yusuke Akita, and Fumihito Arai. "Hydrogel Fluorescence Microsensor with Fluorescence Recovery for Prolonged Stable Temperature Measurements." Sensors 19, no. 23 (November 29, 2019): 5247. http://dx.doi.org/10.3390/s19235247.

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This work describes a hydrogel fluorescence microsensor for prolonged stable temperature measurements. Temperature measurement using microsensors has the potential to provide information about cells, tissues, and the culture environment, with optical measurement using a fluorescent dye being a promising microsensing approach. However, it is challenging to achieve stable measurements over prolonged periods with conventional measurement methods based on the fluorescence intensity of fluorescent dye because the excited fluorescent dye molecules are bleached by the exposure to light. The decrease in fluorescence intensity induced by photobleaching causes measurement errors. In this work, a photobleaching compensation method based on the diffusion of fluorescent dye inside a hydrogel microsensor is proposed. The factors that influence compensation in the hydrogel microsensor system are the interval time between measurements, material, concentration of photo initiator, and the composition of the fluorescence microsensor. These factors were evaluated by comparing a polystyrene fluorescence microsensor and a hydrogel fluorescence microsensor, both with diameters of 20 µm. The hydrogel fluorescence microsensor made from 9% poly (ethylene glycol) diacrylate (PEGDA) 575 and 2% photo initiator showed excellent fluorescence intensity stability after exposure (standard deviation of difference from initial fluorescence after 100 measurement repetitions: within 1%). The effect of microsensor size on the stability of the fluorescence intensity was also evaluated. The hydrogel fluorescence microsensors, with sizes greater than the measurement area determined by the axial resolution of the confocal microscope, showed a small decrease in fluorescence intensity, within 3%, after 900 measurement repetitions. The temperature of deionized water in a microchamber was measured for 5400 s using both a thermopile and the hydrogel fluorescence microsensor. The results showed that the maximum error and standard deviation of error between these two sensors were 0.5 °C and 0.3 °C, respectively, confirming the effectiveness of the proposed method.

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de Beer, Dirk, and Andreas Schramm. "Micro-environments and mass transfer phenomena in biofilms studied with microsensors." Water Science and Technology 39, no. 7 (April 1, 1999): 173–78. http://dx.doi.org/10.2166/wst.1999.0356.

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Direct observations on chemical micro-environment and microbial composition in biofilms are rare. The combination of microsensor and molecular techniques is highly useful for studies on the microbial ecology of biofilms. We shortly describe some applications of microsensors to study mass transfer phenomena and microbial processes in biofilms. It has recent been recognized that biofilms are not always flat layers of cells, but can consist of complex structures allowing liquid flow. Thus the classical view, that transport in biofilms is diffusional, is challenged. In laboratory grown biofilms the effect of convection on mass transfer was demonstrated. The microsensor technique has improved, so that direct in situ measurements in living biofilms are possible. By direct measurements of liquid flow with microsensors we show that in biofilms grown in bioreactors heterogeneity and convectional transport must also be taken into account. For the description of the microbial population we use molecular techniques, such as in situ hybridisation with 16S rRNA-targeted oligonucleotide probes. In a nitrifying-denitrifying biofilm we found a complex nitrifying community consisting of members of the genera Nitrosomonas, Nitrosospira, Nitrobacter and Nitrospira. Their occurrence was correlated with nitrification activity as determined by microsensor measurements.

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Yang, Pengfei, Xiaolong Wen, Zhaozhi Chu, Xiaoming Ni, and Chunrong Peng. "AC/DC Fields Demodulation Methods of Resonant Electric Field Microsensor." Micromachines 11, no. 5 (May 19, 2020): 511. http://dx.doi.org/10.3390/mi11050511.

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Electric field microsensors have the advantages of a small size, a low power consumption, of avoiding wear, and of measuring both direct-current (DC) and alternating-current (AC) fields, which are especially suited to applications in power systems. However, previous reports were chiefly concerned with proposing new structures or improving the resolution, and there are no systematic studies on the signal characteristics of the microsensor output and the demodulation methods under different electric fields. In this paper, the use of an improved resonant microsensor with coplanar electrodes, and the signal characteristics under a DC field, power frequency field, and AC/DC hybrid fields were thoroughly analyzed respectively, and matching demodulation methods derived from synchronous detection were proposed. We theoretically obtained that the frequencies of the detectable electric fields should be less than half of the resonant frequency of the microsensor, and that the sensitivities of the microsensor were identical for AC/DC hybrid fields with different frequencies. Experiments were conducted to verify the proposed demodulation methods. Within electric field ranges of 0–667 kV/m, the uncertainties were 2.4% and 1.5% for the most common DC and 50 Hz power frequency fields, respectively. The frequency characteristic test results of the microsensor were in agreement with those of the theoretical analysis in the range of 0–1 kHz.

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Xiang, Chao, Yulan Lu, Pengcheng Yan, Jian Chen, Junbo Wang, and Deyong Chen. "A Resonant Pressure Microsensor with Temperature Compensation Method Based on Differential Outputs and a Temperature Sensor." Micromachines 11, no. 11 (November 21, 2020): 1022. http://dx.doi.org/10.3390/mi11111022.

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This paper presents the analysis and characterization of a resonant pressure microsensor, which employs a temperature compensation method based on differential outputs and a temperature sensor. Leveraging a silicon-on-insulator (SOI) wafer, this microsensor mainly consists of a pressure-sensitive diagram and two resonant beams (electromagnetic driving and electromagnetic induction) to produce a differential output. The resonators were vacuum packaged with a silicon-on-glass (SOG) cap using anodic bonding and the wire interconnection was realized by sputtering an Au film on highly topographic surfaces using a hard mask. After the fabrication of the resonant pressure microsensor, systematic experiments demonstrated that the pressure sensitivity of the presented microsensor was about 0.33 kPa/Hz. Utilizing the differential frequency of the two resonators and the signal from a temperature sensor to replace the two-frequency signals by polynomial fitting, the temperature compensation method based on differential outputs aims to increase the surface fitting accuracy of these microsensors which have turnover points. Employing the proposed compensation approach in this study, the errors were less than 0.02% FS of the full pressure scale (a temperature range of −40 to 85 °C and a pressure range of 200 kPa to 2000 kPa).

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Nathan, Arokia. "Microsensors for physical signals: Principles, device design, and fabrication technologies." Canadian Journal of Physics 74, S1 (December 1, 1996): 115–30. http://dx.doi.org/10.1139/p96-844.

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Microsensors are miniaturized devices, fabricated using silicon-based and related technologies, that convert input physical and chemical signals into an output electrical signal. The key driving force in microsensor research has been the integrated circuit (IC) and micromachining technologies. The latter, in particular, is fueling tremendous activity in micro-electromechanical systems (MEMS). In terms of technology and design tools, MEMS is at a stage where microelectronics was 30 years ago and is expected to evolve at an equally rapid pace. The synergy between the IC, micromachining, and integrated photonics technologies can potentially spawn a new generation of microsystems that will feature a unique marriage of microsensor, signal-conditioning and -processing circuitry, micromechanics, and optomechanics possibly on a single chip. In this paper, the physical transduction principles, materials considerations, process-fabrication technologies, and computer-aided-design (CAD) tools will be reviewed along with pertinent examples drawn from our microsensor research activity at the Microelectronics Laboratory, University of Waterloo.

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Rathnayake, Rathnayake M. L. D., Shogo Sugahara, Hideaki Maki, Gen Kanaya, Yasushi Seike, and Hisashi Satoh. "High spatial resolution analysis of the distribution of sulfate reduction and sulfide oxidation in hypoxic sediment in a eutrophic estuary." Water Science and Technology 75, no. 2 (November 23, 2016): 418–26. http://dx.doi.org/10.2166/wst.2016.516.

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Bottom hypoxia and consequential hydrogen sulfide (H2S) release from sediment in eutrophic estuaries is a major global environmental issue. We investigated dissolved oxygen, pH and H2S concentration profiles with microsensors and by sectioning sediment cores followed by colorimetric analysis. The results of these analyses were then compared with the physicochemical properties of the bottom water and sediment samples to determine their relationships with H2S production in sediment. High organic matter and fine particle composition of the sediment reduced the oxidation-reduction potential, stimulating H2S production. Use of a microsensor enabled measurement of H2S concentration profiles with submillimetre resolution, whereas the conventional sediment-sectioning method gave H2S measurements with a spatial resolution of 10 mm. Furthermore, microsensor measurements revealed H2S consumption occurring at the sediment surface in both the microbial mat and the sediment anoxic layer, which were not observed with sectioning. This H2S consumption prevented H2S release into the overlying water. However, the microsensor measurements had the potential to underestimate H2S concentrations. We propose that a combination of several techniques to measure microbial activity and determine its relationships with physicochemical properties of the sediment is essential to understanding the sulfur cycle under hypoxic conditions in eutrophic sediments.

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Wen, Xiaolong, Pengfei Yang, Zhouwei Zhang, Zhaozhi Chu, Chunrong Peng, Yutao Liu, Shuang Wu, Bo Zhang, and Fengjie Zheng. "Resolution-Enhancing Structure for the Electric Field Microsensor Chip." Micromachines 12, no. 8 (August 7, 2021): 936. http://dx.doi.org/10.3390/mi12080936.

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Electrostatic voltage is a vital parameter in industrial production lines, for reducing electrostatic discharge harms and improving yields. Due to such drawbacks as package shielding and low resolution, previously reported electric field microsensors are still not applicable for industrial static monitoring uses. In this paper, we introduce a newly designed microsensor package structure, which enhances the field strength inside the package cavity remarkably. This magnification effect was studied and optimized by both theoretical calculation and ANSYS simulation. By means of the digital synthesizer and digital coherent demodulation method, the compact signal processing circuit for the packaged microsensor was also developed. The meter prototype was calibrated above a charged metal plate, and the electric field resolution was 5 V/m, while the measuring error was less than 3 V, from −1 kV to 1 kV in a 2 cm distance. The meter was also installed into a production line and showed good consistency with, and better resolution than, a traditional vibratory capacitance sensor.

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Jung, Dong Geon, Junyeop Lee, Jin Beom Kwon, Bohee Maeng, Hee Kyung An, and Daewoong Jung. "Low-Voltage-Driven SnO2-Based H2S Microsensor with Optimized Micro-Heater for Portable Gas Sensor Applications." Micromachines 13, no. 10 (September 27, 2022): 1609. http://dx.doi.org/10.3390/mi13101609.

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To realize portable gas sensor applications, it is necessary to develop hydrogen sulfide (H2S) microsensors capable of operating at lower voltages with high response, good selectivity and stability, and fast response and recovery times. A gas sensor with a high operating voltage (>5 V) is not suitable for portable applications because it demands additional circuitry, such as a charge pump circuit (supply voltage of common circuits is approximately 1.8–5 V). Among H2S microsensor components, that is, the substrate, sensing area, electrode, and micro-heater, the proper design of the micro-heater is particularly important, owing to the role of thermal energy in ensuring the efficient detection of H2S. This study proposes and develops tin (IV)-oxide (SnO2)-based H2S microsensors with different geometrically designed embedded micro-heaters. The proposed micro-heaters affect the operating temperature of the H2S sensors, and the micro-heater with a rectangular mesh pattern exhibits superior heating performance at a relatively low operating voltage (3–4 V) compared to those with line (5–7 V) and rectangular patterns (3–5 V). Moreover, utilizing a micro-heater with a rectangular mesh pattern, the fabricated SnO2-based H2S microsensor was driven at a low operating voltage and offered good detection capability at a low H2S concentration (0–10 ppm), with a quick response (<51 s) and recovery time (<101 s).

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9

Charavet, Carole, Michel Le Gall, Adelin Albert, Annick Bruwier, and Sophie Leroy. "Patient compliance and orthodontic treatment efficacy of Planas functional appliances with TheraMon microsensors." Angle Orthodontist 89, no. 1 (August 3, 2018): 117–22. http://dx.doi.org/10.2319/122917-888.1.

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ABSTRACT Objectives: To assess patient compliance and treatment efficacy of preventive expansion treatment with removable Planas functional appliances using an integrated microsensor. Materials and Methods: Wear time (WT) and behavior of 69 patients undergoing treatment with Planas functional appliances were assessed and analysed using TheraMon microsensors (Gschladt, Hargelsberg, Austria). Patients were followed up for a period of 9 months, and visits were made every 3 months to download WT data from the microsensor and to assess wearing behavior. From individual WT graphs,10 parameters were derived to characterize compliance for each patient. Treatment efficacy was measured by eight parameters determining the level of expansion after 9 months of treatment. Results: Patients wore their device on average 15.8 ± 5.2 h/d. WT was unrelated to age and gender, but it was positively influenced by patient habits when keeping appliances during eating, sports, care and handling. Treatment efficacy in terms of intercanine and intermolar expansion was 4.4 ± 1.9 mm and 4.6 ± 2.0 mm for the maxilla, and 5.3 ± 2.0 mm and 4.7 ± 2.3 mm for the mandible, respectively. Efficacy was negatively affected by poor compliance (WT < 9 h/d) and by high variability of within-subject WT recordings. Conclusions: Perfect compliance is not necessary to achieve treatment success, but patients should exhibit sufficient wear time to allow maxillary expansion to occur. The TheraMon microsensor offers a new perspective and aid to individualize treatment prescriptions.

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Chen, Siyuan, Jiaxin Qin, Yulan Lu, Bo Xie, Junbo Wang, Deyong Chen, and Jian Chen. "An All-Silicon Resonant Pressure Microsensor Based on Eutectic Bonding." Micromachines 14, no. 2 (February 13, 2023): 441. http://dx.doi.org/10.3390/mi14020441.

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In this paper, an all-Si resonant pressure microsensor based on eutectic bonding was developed, which can eliminate thermal expansion coefficient mismatches and residual thermal stresses during the bonding process. More specifically, the resonant pressure microsensor included an SOI wafer with a pressure-sensitive film embedded with resonators, which was eutectically bonded with a silicon cap for vacuum encapsulation. The all-Si resonant pressure microsensor was carefully designed and simulated numerically, where the use of the silicon cap was shown to effectively address temperature disturbances of the microsensor. The microsensor was then fabricated based on MEMS processes where eutectic bonding was adopted to link the SOI wafer and the silicon cap. The characterization results showed that the temperature disturbances of the resonant pressure microsensor encapsulated with the silicon cap were quantified as −0.82 Hz/°C of the central resonator and −2.36 Hz/°C of the side resonator within a temperature range from −40 °C to 80 °C, which were at least eight times lower than that of the microsensor encapsulated with the glass cap. Compared with the microsensor using the glass cap, the all-silicon microsensor demonstrated an accuracy improvement from 0.03% FS to 0.01% FS and a reduction in short-term frequency fluctuations from 3.2 Hz to 1.5 Hz.

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Sazhin, Oleg. "Flow Microsensor of Thermal Type for Measurements of Gas Fluxes." Applied Mechanics and Materials 249-250 (December 2012): 118–25. http://dx.doi.org/10.4028/www.scientific.net/amm.249-250.118.

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An analytical model of the flow sensor of thermal type is developed. The results of the model application are used to develop a flow microsensor of thermal type with optimal functional characteristics. The technology of microsensor manufacturing is provided. The prototype of the microsensor suitable for use in the mass air flow meter is created. The basic characteristics of the microsensor are presented.

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12

Nagel, David J. "Microsensor clusters." Microelectronics Journal 33, no. 1-2 (January 2002): 107–19. http://dx.doi.org/10.1016/s0026-2692(01)00110-0.

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Brand, O., and H. Baltes. "Microsensor packaging." Microsystem Technologies 7, no. 5-6 (January 1, 2002): 205–8. http://dx.doi.org/10.1007/s005420100110.

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Lee, Chi-Yuan, Chia-Hung Chen, Yun-Hsiu Chien, and Zhi-Yu Huang. "A Proton Battery Stack Real-Time Monitor with a Flexible Six-in-One Microsensor." Membranes 12, no. 8 (August 13, 2022): 779. http://dx.doi.org/10.3390/membranes12080779.

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A proton battery is a hybrid battery produced by combining a hydrogen fuel cell and a battery system in an attempt to obtain the advantages of both systems. As the battery life of a single proton battery is not good, the proton battery stack is developed by connecting in parallel, which can greatly improve the battery life of proton batteries. In order to obtain important information about the proton battery stack in real time, a flexible six-in-one microsensor is embedded in the proton battery stack. This study has successfully developed a health diagnostic tool for a proton battery stack using micro-electro-mechanical systems (MEMS) technology. This study also focused on the innovatively developed hydrogen microsensor, and integrated the voltage, current, temperature, humidity, and flow microsensors, as previously developed by our laboratory, to complete the flexible six-in-one microsensor. Six important internal physical parameters were simultaneously measured during the entire operation of the proton battery stack. It also established a complete database and monitor system in real time to detect the internal health status of the proton cell stack and observe if there were problems, such as water accumulation, aging, or failure, in order to understand the changes and effects of the various physical quantities of long-term operation. The study found that the proton batteries exhibited significant differences in the hydrogen absorb rates and hydrogen release rates. The ceramic circuit board used in the original sensor is replaced by a flexible board to improve problems such as peeling and breaking.

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Pedersen, Ole, Niels Peter Revsbech, and Sergey Shabala. "Microsensors in plant biology: in vivo visualization of inorganic analytes with high spatial and/or temporal resolution." Journal of Experimental Botany 71, no. 14 (April 7, 2020): 3941–54. http://dx.doi.org/10.1093/jxb/eraa175.

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Abstract This Expert View provides an update on the recent development of new microsensors, and briefly summarizes some novel applications of existing microsensors, in plant biology research. Two major topics are covered: (i) sensors for gaseous analytes (O2, CO2, and H2S); and (ii) those for measuring concentrations and fluxes of ions (macro- and micronutrients and environmental pollutants such as heavy metals). We show that application of such microsensors may significantly advance understanding of mechanisms of plant–environmental interaction and regulation of plant developmental and adaptive responses under adverse environmental conditions via non-destructive visualization of key analytes with high spatial and/or temporal resolution. Examples included cover a broad range of environmental situations including hypoxia, salinity, and heavy metal toxicity. We highlight the power of combining microsensor technology with other advanced biophysical (patch–clamp, voltage–clamp, and single-cell pressure probe), imaging (MRI and fluorescent dyes), and genetic techniques and approaches. We conclude that future progress in the field may be achieved by applying existing microsensors for important signalling molecules such as NO and H2O2, by improving selectivity of existing microsensors for some key analytes (e.g. Na, Mg, and Zn), and by developing new microsensors for P.

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Lai, Chi Chih, I. Nan Chang, Hsing Cheng Chang, Chang Chou Hwang, Wen Fung Liu, Chin Hsiang Ma, and Ya Hui Chen. "A Magnetic Microsensor with Temperature Compensation Based on Optical Mechatronic Technology." Materials Science Forum 670 (December 2010): 164–70. http://dx.doi.org/10.4028/www.scientific.net/msf.670.164.

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An optical mechatronic magnetic microsensor with temperature compensation based on fiber Bragg grating (FBG) and microelectromechanical system (MEMS) technologies is demonstrated. Parallel nickel-electroplated cantilever beams are fabricated as an attractive bending mechanism for pushing the optical fiber. Related stress induced cantilever bend caused by magnetic force driving reflective wavelength shift that exactly corresponds with photo-elastic coupling effect to characterize microsensors. Two different cycles of gratings in the same fiber have fabricated to perform the function of magnetic sensing and temperature compensation for reducing temperature-induced bias in magnetic measurement automatically. The sensitivity of 2.238 T/nm with null temperature response has obtained which excited by Nd-Fe-B magnets with residual magnetic strength up to 1.26 Tesla.

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Mei, Jia Bing, Jing Quan Liu, Shui Dong Jiang, Bin Yang, and Chun Sheng Yang. "Platinum Resistance Microsensor for Cryogenic Temperature Measurement." Key Engineering Materials 562-565 (July 2013): 198–203. http://dx.doi.org/10.4028/www.scientific.net/kem.562-565.198.

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Platinum resistance temperature sensor is applied to the temperature range higher than 200K currently. Through studying the principle of platinum temperature sensor, the platinum resistance temperature microsensor can be used in the temperature region between 10K and 200K was studied. It employs symmetrical turn back structure, which effectively avoids the inductance caused by alternating current (AC). Fabrication process based on MEMS technology was illustrated. The platinum film was obtained by direct current (DC) magnetron sputtering deposition and the platinum resistance temperature microsensor was fabricated with 200nm thickness layer film. The relationship between resistance and temperature of platinum microsensor was tested by Quantum QD PPMS instrument. When T>30K and T<30K, TCR of platinum microsensor could achieve 16490ppm/K and 6430ppm/K respectively. Thus, the microsensor can be used as temperature sensing element between 10K and 200K in the cryogenics.

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Gutierrez-Osuna, Ricardo, and Andreas Hierlemann. "Adaptive Microsensor Systems." Annual Review of Analytical Chemistry 3, no. 1 (June 2010): 255–76. http://dx.doi.org/10.1146/annurev.anchem.111808.073620.

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Filthuth, Heinz, Gabriele Eickert, Paul Färber, Henk Jonkers, Lubos Polerecky, and Dirk de Beer. "Microsensor for radioactivity." Journal of Labelled Compounds and Radiopharmaceuticals 50, no. 5-6 (2007): 492–93. http://dx.doi.org/10.1002/jlcr.1215.

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Iftimie, N., R. Steigmann, D. Faktorova, and A. Savin. "Nondestructive evaluation of nanostructured components using Eddy current microsensor." IOP Conference Series: Materials Science and Engineering 1235, no. 1 (March 1, 2022): 012040. http://dx.doi.org/10.1088/1757-899x/1235/1/012040.

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Abstract Nanostructured materials (NMs) are used in the manufacture of microsensors and some MEMS devices, include nanoscale wires, carbon nanotubes, biomaterials, etc. Nondestructive evaluation of structural integrity of NMs can be carried out by optical (SEM, EBDS) and electromagnetic methods (eddy current). Due to small dimensions of the objects to be tested, the eddy current sensors used in detection of possible discontinuities requires miniaturization so that the answer in amplitude and phase shall allow their localization. In the case of thin tubes made of 304 hard stainless steel, with outer diameters 332μm and wall thickness 38 μm used in medical devices, intended for special catheters, their small dimensions and possible discontinuities require encircling sensor working at high frequencies of the order of MHz. The paper presents the investigation of small diameter tubes using an Eddy current microsensor and the results obtained at the detection of artificial flaws in order to increase the probability of detection (POD), for a high reliability coefficient.

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Stefan-van Staden, Raluca-Ioana, Catalina Cioates Negut, Sorin Sebastian Gheorghe, and Paula Sfirloaga. "Stochastic Microsensors Based on Carbon Nanotubes for Molecular Recognition of the Isocitrate Dehydrogenases 1 and 2." Nanomaterials 12, no. 3 (January 28, 2022): 460. http://dx.doi.org/10.3390/nano12030460.

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Two three-dimensional (3D) stochastic microsensors based on immobilization of protoporphyrin IX (PIX) in single-walled carbon nanotubes (SWCNT) and multi-walled carbon nanotubes (MWCNT) decorated with copper (Cu) and gold (Au) nanoparticles were designed and used for the molecular recognition of isocitrate dehydrogenase 1 (IDH1) and isocitrate dehydrogenase 2 (IDH2) in biological samples (brain tumor tissues, whole blood). The linear concentration ranges obtained for the molecular recognition and quantification of IDH1 and IDH2 were: IDH1 (1 × 10−5–1 × 102 ng mL−1) and IDH2 (5 × 10−8 − 5 × 102 ng mL−1). The limits of quantification obtained using the proposed microsensors were: 10 fg mL–1 for IDH1 and 5 × 10−3 fg mL−1 for IDH2. The highest sensitivities were obtained for the microsensor based on MWCNT. High recoveries versus enzyme-linked immunosorbent assay (ELISA) standard method were recorded for the assays of IDH1 and IDH2, all values being higher than 99.00%, with relative standard deviations (RSD) lower than 0.10%.

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Yolcu, Murat, and Nurşen Dere. "A novel copper selective sensor based on ion imprinted 2-vinylpyridine polymer." Canadian Journal of Chemistry 96, no. 12 (December 2018): 1027–36. http://dx.doi.org/10.1139/cjc-2018-0178.

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A novel potentiometric Cu2+-selective microsensor has been developed that is based upon ion imprinted 2-vinylpyridine polymer. The polymer was synthesized using Cu(II) ions, 2-vinylpyridine, methacrylic acid, and ethylene glycol dimethacrylate as a template, functional monomer, and cross-linker, respectively. The resultant polymer was used as ionophore to obtain a selective potentiometric response towards Cu(II) ions in the structure of the PVC membrane. The detection limit of the microsensor was determined to be 8.4 × 10−7 mol/L, and its response time was considerably short (less than 15 s). The prepared microsensor exhibited a near-Nernstian response for Cu(II) ions over the concentration range of 10−1 to 10−6 mol/L, with a slope of 28.5 mV per decade over 2 months, and without any considerable divergence in potentials. The microsensor was effectively performed in a pH range between 4.0 and 7.0 and used as an indicator electrode in the potentiometric titration of Cu(II) ions with EDTA. The proposed microsensor has been successfully demonstrated for the determination of copper in a number of environmental water samples. The obtained potentiometric results were in good harmony with the results obtained by the AAS method.

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Feng, Ke, Jian Hua Tong, Yu Wang, and Shan Hong Xia. "Design‚ Optimization and Simulation of an Electric Field Microsensor Based on PZT Piezoelectric Interdigitated Cantilevers." Key Engineering Materials 645-646 (May 2015): 800–805. http://dx.doi.org/10.4028/www.scientific.net/kem.645-646.800.

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In this paper, we demonstrate the design ‚ optimization and simulation of an electric field microsensor based on PZT piezoelectric interdigitated cantilevers driven. The working principle is introduced, and the induced charge ability of the sensitive cantilever structure is simulated and analyzed using finite element analysis (FEA) method. A multilayer compound cantilever structure (Al/Si3N4/Pt/PZT/Pt/Ti/SiO2/Si) have been designed as the sensing element and PbZrxTi(1-x)O3 (PZT) thin film is used as the piezoelectric material to drive the cantilevers vibrating. This microsensor is fabricated based on the simulation results. The electric field microsensor is tested under the direct current electric field with the field intensity from 0 to 45000 v/m, and the output voltage signal of the microsensor showed a good linear response to the intensity of applied electric field.

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Ring, Andrej, Heiko Sorg, Andreas Weltin, Daniel J. Tilkorn, Jochen Kieninger, Gerald Urban, and Jörg Hauser. "In-vivo monitoring of infection via implantable microsensors: a pilot study." Biomedical Engineering / Biomedizinische Technik 63, no. 4 (July 26, 2018): 421–26. http://dx.doi.org/10.1515/bmt-2016-0250.

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Abstract The most common complication after implantation of foreign material is infection, leading to implant failure and severe patient discomfort. Smoldering-infections proceed inapparently and might not get verified by radiological diagnostics. Early identification of this type of infection might significantly reduce the rate of complications. Therefore, we manufactured a microsensor strip in a hybrid of thin-film and laminate technology in a wafer-level process. It comprises electrochemical, amperometric microsensors for glucose, oxygen and lactate as well as an integrated reference electrode. Microsensors have been implanted in the mouse dorsal skin fold chamber, which got inoculated with a human-pathogen bacterial strain. A selective signal could be measured for all parameters and time points. The infection led to measurable changes of the wound environment as given by a decrease of the oxygen- as well as the glucose-concentration while the lactate concentration increased markedly over time. The given results in this study are the first hints on a promising new tool and should therefore be interpreted as a proof of the principle to show the functionality of the microsensors in an in vivo setting. These microsensors could be used to monitor smoldering infections of implantable foreign materials reducing foreign implant associated complications.

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Song, Yanhui, Ting Yang, Xinfei Zhou, Haitao Zheng, and Shin-ichiro Suye. "A microsensor for hydroquinone and catechol based on a poly(3,4-ethylenedioxythiophene) modified carbon fiber electrode." Analytical Methods 8, no. 4 (2016): 886–92. http://dx.doi.org/10.1039/c5ay02532j.

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A microsensor for hydroquinone and catechol was constructed based on a carbon fiber electrode modified by poly(3,4-ethylenedioxythiophene) by several simple steps. This microsensor exhibited excellent electrochemical activity toward the oxidation of the two diphenol isomers, and satisfying results were obtained.

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Lee, Chi-Yuan, Chia-Hung Chen, Chao-Yuan Chiu, Kuan-Lin Yu, and Lung-Jieh Yang. "Application of Flexible Four-In-One Microsensor to Internal Real-Time Monitoring of Proton Exchange Membrane Fuel Cell." Sensors 18, no. 7 (July 13, 2018): 2269. http://dx.doi.org/10.3390/s18072269.

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In recent years, the development of green energy sources, such as fuel cell, biomass energy, solar energy, and tidal energy, has become a popular research subject. This study aims at a flexible four-in-one microsensor, which can be embedded in the proton exchange membrane fuel cell (PEMFC) for real-time microscopic diagnosis so as to assist in developing and improving the technology of the fuel cell. Therefore, this study uses micro-electro-mechanical systems (MEMS) technology to integrate a micro humidity sensor, micro pH sensor, micro temperature sensor, and micro voltage sensor into a flexible four-in-one microsensor. This flexible four-in-one microsensor has four functions and is favorably characterized by small size, good acid resistance and temperature resistance, quick response, and real-time measurement. The goal was to be able to put the four-in-one microsensor in any place for measurement without affecting the performance of the fuel cell.

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Beltrán-Mejía, Felipe, Claudecir R. Biazoli, and Cristiano M. B. Cordeiro. "Tapered GRIN fiber microsensor." Optics Express 22, no. 25 (December 1, 2014): 30432. http://dx.doi.org/10.1364/oe.22.030432.

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Huang, Zhaoxia, Rhodora L. Villarta-Snow, Glenn J. Lubrano, and George G. Guilbault. "Glutathione Amperometric Enzyme Microsensor." Analytical Letters 27, no. 2 (January 1, 1994): 263–71. http://dx.doi.org/10.1080/00032719408001071.

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Haselman, Mariann, and Sherry Fox. "Microsensor and Microdialysis Technology." Critical Care Nursing Clinics of North America 12, no. 4 (December 2000): 437–46. http://dx.doi.org/10.1016/s0899-5885(18)30080-7.

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30

Huang, Huiliang, and Purnendu K. Dasgupta. "Amperometric microsensor for water." Analytical Chemistry 62, no. 18 (September 1990): 1935–42. http://dx.doi.org/10.1021/ac00217a008.

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Davidson, J. L., D. R. Wur, W. P. Kang, D. L. Kinser, and D. V. Kerns. "Polycrystalline diamond pressure microsensor." Diamond and Related Materials 5, no. 1 (January 1996): 86–92. http://dx.doi.org/10.1016/0925-9635(96)80010-0.

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Buttner, William J., G. Jordan Maclay, and J. R. Stetter. "An integrated amperometric microsensor." Sensors and Actuators B: Chemical 1, no. 1-6 (January 1990): 303–7. http://dx.doi.org/10.1016/0925-4005(90)80220-t.

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Arnold, Georgiana-Luiza, Raluca-Ioana Stefan-van Staden, Iuliana Moldoveanu-Ionita, Eleonora Mihaela Ungureanu, and Luisa-Roxana Popescu-Mandoc. "Azulene Based Stochastic Microsensor." Journal of The Electrochemical Society 163, no. 10 (2016): B563—B566. http://dx.doi.org/10.1149/2.1001610jes.

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YAMADA, Yufu, Yusuke AKITA, Hisataka MARUYAMA, and Fumihito ARAI. "Monodispersed Hydrogel Fluorescence Microsensor." Proceedings of JSME annual Conference on Robotics and Mechatronics (Robomec) 2019 (2019): 2P1—F09. http://dx.doi.org/10.1299/jsmermd.2019.2p1-f09.

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35

Esinenco, D., E. Budianu, I. Bineva, D. Andrijasevic, E. Manea, W. Brenner, and R. Müller. "Integrated optical proximity microsensor." Journal of Luminescence 121, no. 2 (December 2006): 394–98. http://dx.doi.org/10.1016/j.jlumin.2006.08.065.

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Voelker, Rebecca. "Microsensor Monitors Eye Pressure." JAMA 315, no. 15 (April 19, 2016): 1555. http://dx.doi.org/10.1001/jama.2016.3600.

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37

Malcovati, P., H. Baltes, and F. Maloberti. "Progress in Microsensor Interfaces." Sensors Update 1, no. 1 (July 1996): 143–71. http://dx.doi.org/10.1002/1616-8984(199607)1:1<143::aid-seup143>3.0.co;2-f.

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Wu, Chih-Wei, Ting-I. Wu, Wei-Han Chen, and Long-Sun Huang. "DESIGN, FABRICATION, AND TEST OF A SILICATE MICROSENSOR." Biomedical Engineering: Applications, Basis and Communications 21, no. 06 (December 2009): 389–94. http://dx.doi.org/10.4015/s1016237209001519.

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This work describes a portable microsensor for analyzing the silicate concentration in water. Conventionally adopted silicate analysis methods involve bulky instrumentation that are limited in portability and immediateness. The proposed silicate microsensor consists of a microliquid core waveguide, passive spiral micromixer, and bubble traps that possess excellent signal enhancement properties. The microsensor size is 52 × 26 mm, while each measurement requires only 115 μl of a sample and reagents, thereby reducing the sample requirement for a considerable amount of time and work to collect expensive reagents. The spiral micromixer has a mixing capability superior to that of a premix mixture. Bubble traps have been developed to trap air bubbles formed in the microchannel in order to prevent gas bubbles from interfering with the measurements. As a linear function of silicate concentration, the absorbance response ranges from 0 to 250 nM. Additionally, the linearity is excellent with a linear R value of 0.9985 and the experimental detection limit is 8.9 nM. The proposed portable microsensor significantly contributes to aqueous inspection, subsequently creating a highly value-added technology for chemical sensors and microsystems.

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Feng, Lin, Tomohiro Kawahara, Yoko Yamanishi, Masaya Hagiwara, Kazuhiro Kosuge, and Fumihito Arai. "On-Demand and Size-Controlled Production of Droplets by Magnetically Driven Microtool." Journal of Robotics and Mechatronics 24, no. 1 (February 20, 2012): 133–40. http://dx.doi.org/10.20965/jrm.2012.p0133.

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We have successfully produced size-controlled emulsion droplets on a chip by adjusting the vibration frequency for MMT. The novelty of this work is the fabrication of a thin coplanar Au electrode on the substrate of a microchip to work as a microsensor, and this microsensor contributed to a droplet-generation system with size estimation. When a droplet passes through the microsensor in the microchannel, it causes a change in the capacitance across a pair of microelectrodes in the microchannel, depending on the size of the droplet. We monitored the change in impedance in real time. The microsensor provided an output voltage proportional to the size of the droplet. The sensor output was observed by an oscilloscope at the primary stage. Manually we estimated the size and set a new actuation frequency for MMT to achieve on-demand and size control of the droplet. Real-time droplet detection was applied in this system. By monitoring the actuation frequency for MMT, size-controlled and ondemand droplet generation could be successfully carried out.

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Said, Mohamed Hadj, Farès Tounsi, Libor Rufer, Hatem Trabelsi, Brahim Mezghani, and Andrea Cavallini. "Magnetic-field CMOS microsensor for low-energy electric discharge detection." Journal of Sensors and Sensor Systems 7, no. 2 (October 30, 2018): 569–75. http://dx.doi.org/10.5194/jsss-7-569-2018.

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Abstract. This paper addresses the development and characterization of a non-intrusive silicon-based microsensor, which can detect electric partial discharges in electrical insulation equipment. Early partial discharge detection prevents failures and can be used to optimize maintenance operations. Despite the potential that CMOS technology offers, miniaturized electric discharge detector has neither been investigated nor implemented, until now. The developed microsensor demonstrates its ability to record electric discharge emission thanks to the presence of a miniaturized planar inductor. The squared inductor of 50 turns with a side length of 1.5 mm used in our sensor has been fabricated on top of a silicon substrate in a CMOS technology. The total inductor wire length of loop antenna is 30 cm to achieve 100 MHz bandwidth. Using the microsensor at 1 cm from the discharge site, a damped sinusoidal induced voltage with an amplitude of 2 V has been measured at its output. We observed that the output signal spectrum is highly concentrated around a central resonance frequency, which remains constant. The main advantage of such design resides in its monolithic integration added to the high autonomy, which improves the microsensor efficiency.

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Cheng, Xudong, Arindom Datta, Hongseok Choi, Xugang Zhang, and Xiaochun Li. "Study on Embedding and Integration of Microsensors Into Metal Structures for Manufacturing Applications." Journal of Manufacturing Science and Engineering 129, no. 2 (September 25, 2006): 416–24. http://dx.doi.org/10.1115/1.2515456.

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Real time monitoring, diagnosis, and control of numerous manufacturing processes is of critical importance in reducing operation costs, improving product quality, and shortening response time. Current sensors used in manufacturing are normally unable to provide measurements with desired spatial and temporal resolution at critical locations in metal tooling structures that operate in hostile environments (e.g., elevated temperatures and severe strains). Microsensors are expected to offer tremendous benefits for real time sensing in manufacturing processes. Rapid tooling, a layered manufacturing process, could allow microsensors to be placed at any critical location in metal tooling structures. However, a viable approach is needed to effectively integrate microsensors into metal structures during the process. In this study, a novel batch production of metal embedded microsensor units was realized by transferring thin-film sensors from silicon wafers directly into nickel substrates through standard microfabrication and electroplating techniques. Ultrasonic metal welding (USMW) was studied to obtain optimized process parameters and then used to integrate nickel embedded thin-film thermocouple (TFTC) units into copper workpieces. The embedded TFTCs successfully survived the welding tests, validating that USMW is a viable method to integrate microsensors to metallic tool materials. Moreover, the embedded microsensors were also able to measure the transient temperature in situ at 50μm directly beneath the welding interface during welding. The transient temperatures measured by the metal embedded TFTCs provide strong evidence that the heat generation is not critical for weld formation during USMW. Metal embedded microsensors yield great potential to improve fundamental understanding of numerous manufacturing processes by providing in situ sensing data with high spatial and temporal resolution at critical locations.

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Hadj Said, M., F. Tounsi, SG Surya, B. Mezghani, M. Masmoudi, and VR Rao. "A MEMS-based shifted membrane electrodynamic microsensor for microphone applications." Journal of Vibration and Control 24, no. 1 (March 31, 2016): 208–22. http://dx.doi.org/10.1177/1077546316637298.

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In this paper we present a multidisciplinary modeling of a MEMS-based electrodynamic microsensor, when an additional vertical offset is defined, aiming acoustic applications field. The principle is based on the use of two planar inductors, fixed outer and suspended inner. When a DC current is made to flow through the outer inductor, a magnetic field is produced within the suspended inner one, located on a membrane top. In our modeling, the magnetic field curve, as a function of the vertical fluctuation magnitude, shows that the radial component was maximum and stationary for a specific vertical location. We demonstrate in this paper that the dynamic response of the electrodynamic microsensor was very appropriate for acting as a microphone when the membrane is shifted to a certain vertical position, which represents an improvement of the microsensor's basic design. Thus, a proposed technological method to ensure this offset of the inner inductor, by using wafer bonding method, is discussed. On this basis, the mechanical and electrical modeling for the new microphone design was performed using both analytic and Finite Element Method. Firstly, the resonance frequency was set around 1.6 kHz, in the middle of the acoustic band (20 Hz – 20 kHz), then the optimal location of the inner average spiral was evaluated to be around 200µm away from the diaphragm edge. The overall dynamic sensitivity was evaluated by coupling the lumped elements from different domains interfering during the microphone function. Dynamic sensitivity was found to be 6.3 μV/Pa when using 100 µm for both gap and vertical offset. In conclusion, a bandwidth of 37.6 Hz to 26.5 kHz has been found which is wider compared to some conventional microphones.

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Katritzky, Alan R., and Rick J. Offerman. "The Development of New Microsensor Coatings and a Short Survey of Microsensor Technology." Critical Reviews in Analytical Chemistry 21, no. 2 (September 1989): 83–113. http://dx.doi.org/10.1080/10408348908051628.

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44

Eto, T. K., B. J. Costello, S. W. Wenzel, R. M. White, and B. Rubinsky. "Viscosity Sensing With Lamb-Wave Microsensor: Dimethylsulfoxide Solution Viscosity as a Function of Temperature." Journal of Biomechanical Engineering 115, no. 3 (August 1, 1993): 329–31. http://dx.doi.org/10.1115/1.2895494.

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Recently, a new microsensor employing low-velocity ultrasonic Lamb waves was developed and demonstrated to be capable of measuring the viscosity of solutions in small volumes. The microsensor, when attached to a temperature-controlled stage, can measure viscosity as a function of temperature. In this investigation, the ultrasonic Lamb-wave oscillator is employed to experimentally measure the viscosity of dimethylsulfoxide (Me2SO) solutions as a function of temperature. The microsensor and the experimental procedure are described and results for 1M, 3M, and 5M Me2SO aqueous solutions are presented. Dimethylsulfoxide is a compound commonly employed as a cryoprotectant in cryopreservation, the low-temperature preservation of biological materials. The temperature dependence of viscosity obtained through this study can be used in determining the probability for ice nucleation in biological materials, a parameter of importance during cryopreservation.

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Huo, Doudou, Daodong Li, Songzhi Xu, Yujie Tang, Xueqian Xie, Dayong Li, Fengming Song, Yali Zhang, Aixue Li, and Lijun Sun. "Disposable Stainless-Steel Wire-Based Electrochemical Microsensor for In Vivo Continuous Monitoring of Hydrogen Peroxide in Vein of Tomato Leaf." Biosensors 12, no. 1 (January 12, 2022): 35. http://dx.doi.org/10.3390/bios12010035.

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As one of the pivotal signal molecules, hydrogen peroxide (H2O2) has been demonstrated to play important roles in many physiological processes of plants. Continuous monitoring of H2O2 in vivo could help understand its regulation mechanism more clearly. In this study, a disposable electrochemical microsensor for H2O2 was developed. This microsensor consists of three parts: low-cost stainless-steel wire with a diameter of 0.1 mm modified by gold nanoparticles (disposable working electrode), an untreated platinum wire with a diameter of 0.1 mm (counter electrode), and an Ag/AgCl wire with a diameter of 0.1 mm (reference electrode), respectively. The microsensor could detect H2O2 in levels from 10 to 1000 µM and exhibited excellent selectivity. On this basis, the dynamic change in H2O2 in the vein of tomato leaf under high salinity was continuously monitored in vivo. The results showed that the production of H2O2 could be induced by high salinity within two hours. This study suggests that the disposable electrochemical microsensor not only suits continuously detecting H2O2 in microscopic plant tissue in vivo but also reduces the damage to plants. Overall, our strategy will help to pave the foundation for further investigation of the generation, transportation, and elimination mechanism of H2O2 in plants.

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Kersjes, R., and W. Mokwa. "Microsensor techniques for cardiovascular systems." Minimally Invasive Therapy & Allied Technologies 6, no. 3 (January 1997): 199–203. http://dx.doi.org/10.3109/13645709709153319.

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Raghunathan, V., C. Schurgers, Sung Park, and M. B. Srivastava. "Energy-aware wireless microsensor networks." IEEE Signal Processing Magazine 19, no. 2 (March 2002): 40–50. http://dx.doi.org/10.1109/79.985679.

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48

Pinnaduwage, L. A., A. Gehl, D. L. Hedden, G. Muralidharan, T. Thundat, R. T. Lareau, T. Sulchek, et al. "A microsensor for trinitrotoluene vapour." Nature 425, no. 6957 (October 2003): 474. http://dx.doi.org/10.1038/425474a.

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Fries, David, and Geran Barton. "3D MICROSENSOR IMAGING ARRAYS NETWORKS." Additional Conferences (Device Packaging, HiTEC, HiTEN, and CICMT) 2015, DPC (January 1, 2015): 000348–78. http://dx.doi.org/10.4071/2015dpc-ta33.

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2D microsensor arrays can permit spatial distribution measurements of the sensed parameter and enable high resolution sensing visualizations. Measuring constituents in a flowing media, such as air or liquid could benefit from such flow through or flow across imaging systems. These flow imagers can have applications in mobile robotics and non-visible imagery, and alternate mechanical systems of perception, process control and environmental observations. In order to create rigid-conformal, large area imaging systems we have in the past merged flexible PCB substrates with rigid constructions from 3D printing. This approach merges the 2D flexible electronics world of printed circuits with the 3D printed packaging world. Extending this 2D flow imaging concept into the third dimension permits 3D flow imaging networks, architectures and designs and can create a new class of sensing systems. Using 3D printing, 3D printed filaments, nets and microsensor cages, can be combined into integrated designs to generate distributed 3D imaging networks and camera systems for a variety of sensory applications.

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WALT, D. R., T. M. BLICHARZ, R. B. HAYMAN, D. M. RISSIN, M. BOWDEN, W. L. SIQUEIRA, E. J. HELMERHORST, et al. "Microsensor Arrays for Saliva Diagnostics." Annals of the New York Academy of Sciences 1098, no. 1 (March 1, 2007): 389–400. http://dx.doi.org/10.1196/annals.1384.031.

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Journal articles on the topic 'Microsensor'

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