Journal articles: 'Chemosensori'

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Ying, Liang, and Yu Chun-Wei. "A Chemosensor for Fe3+ Detection Derived from Pyrene." Academic Journal of Chemistry, no. 73 (August 20, 2022): 42–46. http://dx.doi.org/10.32861/ajc.73.42.46.

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It is of great significance to find a suitable method to detect Fe3+ due to its essential role in human and animal health. Artificial chemosensors have been a suitable method in view of simple preparation, fast response, et al. [Aim]: A selective Fe3+ chemosensor was designed. [Method]: A novel Fe3+-selective chemosensor was rationally designed based on pyrene derivative by the introduction of benzoyl hydrazine. [Results] The proposed chemosensor presented good selectivity for Fe3+ in presence of other common metal ions. [Conclusions]: The proposed idea can be used for reference to enrich chemosensors.

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Goyal, Hina, Ibrahim Annan, Deepali Ahluwalia, Arijit Bag, and Rajeev Gupta. "Discriminative ‘Turn-on’ Detection of Al3+ and Ga3+ Ions as Well as Aspartic Acid by Two Fluorescent Chemosensors." Sensors 23, no. 4 (February 6, 2023): 1798. http://dx.doi.org/10.3390/s23041798.

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In this work, two Schiff-base-based chemosensors L1 and L2 containing electron-rich quinoline and anthracene rings were designed. L1 is AIEE active in a MeOH-H2O solvent system while formed aggregates as confirmed by the DLS measurements and fluorescence lifetime studies. The chemosensor L1 was used for the sensitive, selective, and reversible ‘turn-on’ detection of Al3+ and Ga3+ ions as well as Aspartic Acid (Asp). Chemosensor L2, an isomer of L1, was able to selectively detect Ga3+ ion even in the presence of Al3+ ions and thus was able to discriminate between the two ions. The binding mode of chemosensors with analytes was substantiated through a combination of 1H NMR spectra, mass spectra, and DFT studies. The ‘turn-on’ nature of fluorescence sensing by the two chemosensors enabled the development of colorimetric detection, filter-paper-based test strips, and polystyrene film-based detection techniques.

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Ikeda, Hiroshi. "Diversely Responsive Turn-On Fluorescent Cyclodextrin Chemosensors: Guest Selectivities and Mechanism Insights." Chemosensors 8, no. 3 (July 1, 2020): 48. http://dx.doi.org/10.3390/chemosensors8030048.

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Chemosensors have attracted considerable attention among the numerous strategies for detecting organic molecules in water. A turn-off mechanism was previously employed for the construction of a cyclodextrin (CD) chemosensor. This mechanism is greatly effective but has several shortcomings. In order to overcome these shortcomings, new fluorescent chemosensors NC0αCD, NC0βCD, and NC0γCD, which were (7-nitrobenz-2-oxa-1,3-diazol-4-yl)amine-modified α-CD, β-CD, and γ-CD, respectively, were prepared. Their guest selectivities were different from those of previously reported CD chemosensors. Here, the mechanism of new CD chemosensors was investigated using nuclear magnetic resonance (NMR) spectroscopy and molecular mechanics calculations. The fluorescence intensity of NC0βCD and NC0γCD slightly decreased and largely increased, respectively, upon the addition of ursodeoxycholic acid as a guest. This is due to the fact that the fluorophore of NC0βCD moved away to the hydrophilic bulk water to form hydrogen bonds between the host and the guest, while the fluorophore of NC0γCD remained located at the primary hydroxy side of the γ-CD unit to form a stable inclusion complex with hydrogen bonds between the fluorophore and the guest. NC0αCD also acted as a turn-on chemosensor for small guests, which could not be detected by the previous CD chemosensors. The motion restriction of the fluorophore through the generation of inclusion complexes could also contribute to increase in fluorescence intensity.

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Mao, Hua, John B. Thorne, Jennifer S. Pharr, and Robert E. Gawley. "Effect of crown ether ring size on binding and fluorescence response to saxitoxin in anthracylmethyl monoazacrown ether chemosensors." Canadian Journal of Chemistry 84, no. 10 (October 1, 2006): 1273–79. http://dx.doi.org/10.1139/v06-093.

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Convenient macrocyclization synthetic routes for the preparation of different-sized monoaza anthracylmethyl crown ether chemosensors (15-crown-5, 18-crown-6, 21-crown-7, 24-crown-8, and 27-crown-9) are described. Evaluation of these crowns as chemosensors for saxitoxin revealed that the larger crowns have moderately higher binding constants, with the 27-crown-9 chemosensor having the largest binding constant (2.29 × 105 (mol/L)–1). Fluorescence enhancements of 100% were observed at saxitoxin concentrations of 5 µmol/L, which is close to the detection limit in mouse bioassay.Key words: anthracene, crown ethers, saxitoxin, paralytic shellfish poison (PSP), binding constants; chemosensors.

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Ghazalli, Nur Fatiha Nur, Nurul Husna Sabran, Juan Matmin, Mohamad Azani Jalani, and Hendrik Oktendy Lintang. "Phosphorescent Vapochromic Responses of Copper(I) Complex Bearing Pyrazole Ligands for Detection of Alcohol Derivatives." Malaysian Journal of Fundamental and Applied Sciences 18, no. 1 (February 28, 2022): 138–47. http://dx.doi.org/10.11113/mjfas.v18n1.2560.

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The methodical study of trinuclear copper(I) metal complexes phosphorescent vapochromic chemosensor via metal-metal interactions for sensing various volatile organic compounds has piqued the interest of many researchers. Herein, we highlighted the performance of chemosensors trinuclear copper(I) pyrazolate complexes (2Pz1‒2Pz5) with different molecular design short alkyl side chains from the respective pyrazole ligands. The synthesized complexes had demonstrated a high phosphorescent sensing capacity of various alcohol derivatives. Due to weak metal-metal interactions, the complexes give emission bands centered around 553-644 nm at an excitation of 280 nm. We found that the only 2Pz3 chemosensors showed quenching phenomena with a significant decrease in its emission intensity of 100% for exposure in 5 minutes with irreversible performance. Interestingly, we also found that the shifting of the emission center due to the disruption of metal-metal interaction performed by chemosensor 2Pz5 resulting in the best detection performance of methanol and ethanol (∆λ= 60 nm) and propanol (∆λ = 22 nm) showing autonomous recovery within 15 minutes. Based on the findings, the specific balance, such as rigidity and amphiphilicity in the molecular design of chemosensors, is important for the detection of vapors via supramolecular interactions.

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Mohammadi, Asadollah, and Jeyran Jabbari. "Simple naked-eye colorimetric chemosensors based on Schiff-base for selective sensing of cyanide and fluoride ions." Canadian Journal of Chemistry 94, no. 7 (July 2016): 631–36. http://dx.doi.org/10.1139/cjc-2016-0039.

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The present work describes the design and synthesis of simple colorimetric chemosensors based on Schiff-base for highly selective sensing of cyanide and fluoride ions. The chemosensor S2, containing an electron withdrawing group (EWG), displayed selective sensing properties for both cyanide and fluoride ions. The interaction of S2 with F– and CN– ions provides remarkable colorimetric responses from yellow to purple, enabling naked-eye sensing without any spectroscopic instrumentation. The mechanism of anion binding with chemosensor S2 showed one-to-one stoichiometry by Job’s plot. The mechanism of interaction between the S2 and CN– ions has been confirmed by the 1H NMR titration experiments. Furthermore, the detection limits of chemosensor S2 towards F– and CN– ions were found to be 3.7 and 1.2 μmol/L, respectively.

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Priyangga, Krisfian Tata Aneka, Yehezkiel Steven Kurniawan, Keisuke Ohto, and Jumina Jumina. "Review on Calixarene Fluorescent Chemosensor Agents for Various Analytes." Journal of Multidisciplinary Applied Natural Science 2, no. 1 (January 15, 2022): 23–40. http://dx.doi.org/10.47352/jmans.2774-3047.101.

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Calixarenes are well-known supramolecular host molecules with versatile applications. Over the past decades, hundreds of selective and sensitive detections of several analytes have been reported by employing calixarenes as the chemosensor agent. The detection and quantification of metal ions and anions are crucial as heavy metal ions are harmful to living organisms, while monitoring anions is pivotal in the environmental samples. On the other hand, detecting and quantifying biomolecules and neutral molecules are critical due to their irreplaceable role in human health. In this review, we summarized the application of calixarenes as the supramolecular chemosensor agent for detecting metal ions, anions, biomolecules, and neutral molecules through fluorescent spectroscopy to give brief information on the design and development of the chemosensor field. This review updates the world with the application of calixarene derivatives as fluorescent chemosensors and challenges researchers to design and develop better chemosensor agents in the future.

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Huang, Qing, Qiao Li, Hai-Li Zhang, Wei Zhu, Wen-Juan Qu, Qi Lin, Hong Yao, You-Ming Zhang, and Tai-Bao Wei. "A novel fluorometric chemosensor based on imidazo[4,5-b]phenazine-2-thione for ultrasensitive detection and separation of Hg²⁺ in aqueous solution." Canadian Journal of Chemistry 100, no. 4 (April 2022): 280–84. http://dx.doi.org/10.1139/cjc-2021-0244.

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We synthesized and developed 1,3-dihydro-2H-imidazo[4,5-b]phenazine-2-thione as a ratiometric chemosensor for Hg2+ recognition in a DMSO/H2O (v/v = 9:1) binary solution. We rationally introduced the phenazine imidazole group as the fluorophore and the thione moiety as the recognition site to bind Hg2+. Interestingly, the chemosensor showed an ultrasensitive response to Hg2+, and the lowest limit of detection was 0.167 nM. In addition, it can also separate Hg2+ from aqueous solutions with excellent ingestion capacity, with an adsorption ratio of up to 96%. Furthermore, ion test strips based on chemosensors were fabricated for convenient and efficient detection of Hg2+.

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Sousa, Rui P. C. L., Raquel C. R. Gonçalves, Susana P. G. Costa, Rita B. Figueira, and Maria Manuela M. Raposo. "Heterocyclic Aldehydes Based on Thieno[3,2-b]thiophene Core: Synthesis and Preliminary Studies as Ion Optical Chemosensors." Cells 3, no. 1 (November 13, 2020): 88. http://dx.doi.org/10.3390/ecsoc-24-08092.

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Heterocyclic aldehydes show a variety of optical properties and the versatility of their reactivity allows them to yield a wide range of more complex compounds, with application in areas such as medicinal, materials and supramolecular chemistry. The biological and environmental relevance of certain molecules and ions turns them into targets for the design of molecular recognition systems. Recently, heterocyclic aldehydes have been reported in the literature as ion chemosensors. Following the group’s work on optical chemosensors, for the detection and quantification of ions and molecules with environmental and medicinal relevance, this work reports the synthesis and characterization of two heterocyclic aldehydes based on the thieno[3,2-b]thiophene core, by Suzuki coupling, as well as the synthesis of the corresponding precursors. Preliminary chemosensory studies for the synthesized heterocyclic aldehydes in the presence of selected cations were also performed, in solution, in order to determine their potential application as optical chemosensors.

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Verdejo, Begoña, Mario Inclán, María Paz Clares, Irene Bonastre-Sabater, Mireia Ruiz-Gasent, and Enrique García-España. "Fluorescent Chemosensors Based on Polyamine Ligands: A Review." Chemosensors 10, no. 1 (December 22, 2021): 1. http://dx.doi.org/10.3390/chemosensors10010001.

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Polyamine ligands are water-soluble receptors that are able to coordinate, depending on their protonation degree, either metal ions, anionic, or neutral species. Furthermore, the presence of fluorescent signaling units allows an immediate visual response/signal. For these reasons, they can find applications in a wide variety of fields, mainly those where aqueous media is necessary, such as biological studies, wastewater analysis, soil contamination, etc. This review provides an overview of the recent developments in the research of chemosensors based on polyamine ligands functionalized with fluorescent signaling units. The discussion focuses on the design, synthesis, and physicochemical properties of this type of fluorescent chemosensors in order to analyze the applications associated to the sensing of metal ions, anions, and neutral molecules of environmental and/or biological interest. To facilitate a quick access and overview of all the chemosensors covered in this review, a summary table of the chemosensor structures and analytes, with all the corresponding references, is also presented.

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Leathers, Kyle W., Brenden T. Michaelis, and Matthew A. Reidenbach. "Interpreting the Spatial-Temporal Structure of Turbulent Chemical Plumes Utilized in Odor Tracking by Lobsters." Fluids 5, no. 2 (May 24, 2020): 82. http://dx.doi.org/10.3390/fluids5020082.

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Olfactory systems in animals play a major role in finding food and mates, avoiding predators, and communication. Chemical tracking in odorant plumes has typically been considered a spatial information problem where individuals navigate towards higher concentration. Recent research involving chemosensory neurons in the spiny lobster, Panulirus argus, show they possess rhythmically active or ‘bursting’ olfactory receptor neurons that respond to the intermittency in the odor signal. This suggests a possible, previously unexplored olfactory search strategy that enables lobsters to utilize the temporal variability within a turbulent plume to track the source. This study utilized computational fluid dynamics to simulate the turbulent dispersal of odorants and assess a number of search strategies thought to aid lobsters. These strategies include quantification of concentration magnitude using chemosensory antennules and leg chemosensors, simultaneous sampling of water velocities using antennule mechanosensors, and utilization of antennules to quantify intermittency of the odorant plume. Results show that lobsters can utilize intermittency in the odorant signal to track an odorant plume faster and with greater success in finding the source than utilizing concentration alone. However, the additional use of lobster leg chemosensors reduced search time compared to both antennule intermittency and concentration strategies alone by providing spatially separated odorant sensors along the body.

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Koralli, Panagiota, and Dionysios E. Mouzakis. "Advances in Wearable Chemosensors." Chemosensors 9, no. 5 (April 29, 2021): 99. http://dx.doi.org/10.3390/chemosensors9050099.

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In this review, the latest research on wearable chemosensors is presented. In focus are the results from open literature, mainly from the last three years. The progress in wearable chemosensors is presented with attention drawn to the measuring technologies, their ability to provide robust data, the manufacturing techniques, as well their autonomy and ability to produce power. However, from statistical studies, the issue of patients’ trust in these technologies has arisen. People do not trust their personal data be transferred, stored, and processed through the vastness of the internet, which allows for timely diagnosis and treatment. The issue of power consumption and autonomy of chemosensor-integrated devices is also studied and the most recent solutions to this problem thoroughly presented.

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Rokhmah, Nevi Faizatu, Muhammad Idham Darussalam Mardjan, and Bambang Purwono. "Synthesis of Vanillin-Azine as Colorimetric Chemosensor of Sulfide Anion." Indonesian Journal of Chemistry 22, no. 6 (November 16, 2022): 1490. http://dx.doi.org/10.22146/ijc.71569.

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Vanillin-azine (VA), (4,4'-((1E,1'E)-hydrazine-1,2-diylidenebis(methane-lylidene))bis(2-methoxyphenol) has been synthesized from vanillin and tested as anion colorimetric chemosensors for sulfide anion. The VA was obtained from a condensation reaction between vanillin and hydrazine hydrate with a mol ratio of 2:1 mol for 24 h at room temperature. The structure was elucidated using FTIR, GC-MS, 1H-NMR, and 13C-NMR spectrometers. The VA compound was examined as a colorimetric chemosensor for sulfide anion over several anions of CN−, F−, Cl−, Br−, I−, N3−, CH3COO−, and NO3−. The structure of the product showed agreement with all spectrometric data. The VA chemosensor tests indicated only selective to S2− anion followed by a color change from colorless to light blue in a DMF:HEPES buffer solution (DMF:HBS) medium (9:1, v/v, 10 mM, pH = 7.4). Filter paper strips can detect S2− anion with a color change from white to yellow. The VA chemosensor has a limit of detection (LOD) of 5.4 × 10−4 M, therefore, the VA chemosensor can be applied to detect S2− anion in tap water.

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Gou, Gao Zhang, He Ping Yan, Shi Juan Xu, Na Wu, Bo Zhou, and Wei Liu. "1,8-Naphthyridine Modified Rhodamine B Derivatives: Turn-On Colorimetric Sensor for Cu²⁺." Advanced Materials Research 881-883 (January 2014): 1079–82. http://dx.doi.org/10.4028/www.scientific.net/amr.881-883.1079.

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A 1,8-naphthyridine modified rhodamine B derivative, one Cu2+-selective chemosensors was designed, synthesized and characterized, which display a high selectivity for Cu2+among environmentally and biologically relevant metal ions. It can detect Cu2+in aqueous solution selectively with a dramatic colour change from colorless to magenta. The detection mechanism involves a ring-opening process as a consequence of metal complex formation. Jobs plots study indicated that the chemosensor chelated Cu2+with 2:1 stoichiometry.

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Martins, Cátia D. F., Patrícia M. R. Batista, M. Manuela M. Raposo, and Susana P. G. Costa. "Crown Ether Benzoxazolyl-Alanines as Fluorimetric Chemosensors for the Detection of Palladium in Aqueous Environment." Chemistry Proceedings 3, no. 1 (November 14, 2020): 5. http://dx.doi.org/10.3390/ecsoc-24-08310.

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Palladium has wide application in different contexts and, as a consequence, high levels of palladium in the environment have been reported, representing a risk to human health. Considering the interest to develop more selective and sensitive chemosensors for this analyte, two novel benzoxazolyl-alanine derivatives bearing a crown ether moiety were studied as potential fluorimetric chemosensors for palladium detection. Preliminary chemosensory studies for these unnatural amino acids in the presence of selected metal cations were performed in acetonitrile solution and in aqueous mixtures of sodium dodecyl sulfate (SDS, 20 mM, pH 7.5) solution with acetonitrile, 90:10 v/v. In acetonitrile solution, these probes had a fluorescence response for different cations but, most importantly, in SDS aqueous solution both compounds displayed a selective fluorescence response in the presence of palladium.

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Wu, Qin, Tao Tao, Yunxia Zhao, and Wei Huang. "A Flexible Chemosensor Based on Colorimetric and Fluorescent Dual Modes for Rapid and Sensitive Detection of Hypochlorite Anion." Sensors 21, no. 23 (December 3, 2021): 8082. http://dx.doi.org/10.3390/s21238082.

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A flexible chemosensor has been developed based on colorimetric and fluorescent dual modes using tetraphenylethylene-centered tetraaniline (TPE4A) for rapid and sensitive detection of hypochlorite anion. The fluorescent probe TPE4A exhibits a unique aggregation-induced emission (AIE) character which is proved by a blue shift of the fluorescent peak from 544 to 474 nm with the water equivalents increasing. With the addition of hypochlorite in solution, the absorbance of the probe changes and the responding fluorescence color can be observed to change from light green to purple. The detection limit of hypochlorite is 1.80 × 10−4 M in solution, and the visual detection limit is 1.27 µg/cm2 with the naked eye for the flexible paper-based chemosensor. The proposed flexible chemosensors show a good selectivity and sensitivity which has great potential for effective detection of hypochlorite anions without any spectroscopic instrumentation.

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Queirós, Carla, Vítor A. S. Almodôvar, Fábio Martins, Andreia Leite, Augusto C. Tomé, and Ana M. G. Silva. "Synthesis of Novel Diketopyrrolopyrrole-Rhodamine Conjugates and Their Ability for Sensing Cu2+ and Li+." Molecules 27, no. 21 (October 25, 2022): 7219. http://dx.doi.org/10.3390/molecules27217219.

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The search for accurate and sensitive methods to detect chemical substances, namely cations and anions, is urgent and widely sought due to the enormous impact that some of these chemical species have on human health and on the environment. Here, we present a new platform for the efficient sensing of Cu2+ and Li+ cations. For this purpose, two novel photoactive diketopyrrolopyrrole-rhodamine conjugates were synthesized through the condensation of a diketopyrrolopyrrole dicarbaldehyde with rhodamine B hydrazide. The resulting chemosensors 1 and 2, bearing one or two rhodamine hydrazide moieties, respectively, were characterized by 1H and 13C NMR and high-resolution mass spectrometry, and their photophysical and ion-responsive behaviours were investigated via absorption and fluorescence measurements. Chemosensors 1 and 2 displayed a rapid colorimetric response upon the addition of Cu2+, with a remarkable increase in the absorbance and fluorescence intensities. The addition of other metal ions caused no significant effects. Moreover, the resulting chemosensor-Cu2+ complexes revealed to be good probes for the sensing of Li+ with reversibility and low detection limits. The recognition ability of the new chemosensors was investigated by absorption and fluorescence titrations and competitive studies.

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Jeon, Hyokyung, Hwahui Ryu, Inho Nam, and Dong-Youn Noh. "Heteroleptic Pt(II)-dithiolene-based Colorimetric Chemosensors: Selectivity Control for Hg(II) Ion Sensing." Materials 13, no. 6 (March 19, 2020): 1385. http://dx.doi.org/10.3390/ma13061385.

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Hg2+ ions can accumulate in the natural environment and in organisms, where they cause damage to the central nervous system. Therefore, the detection of Hg2+ ions is essential for monitoring environmental contamination and human health. Herein, we demonstrate a simple method for tuning chemosensor signal ratios that significantly increased chemosensor selectivity for Hg2+ detection. Selectivity tuning was accomplished for chemosensors of the type (diphosphine)Pt(dmit), bearing the two different terminal groups 1,2-bis(diphenylphosphino)ethane (dppe) and 1,2-bis[bis(pentafluorophenyl)phosphino]ethane) (dfppe) due to the modulation of specific intermolecular interactions between the dmit ligand and Hg2+ ion. The structure exhibited a large pseudo-Stokes shift, which was advantageous for the internal reference signal and for eliminating potential artifacts. Straightforward chain-end manipulation enabled the tuning of chemosensor properties without additional chemical alterations. Based on these findings, we propose a new platform for improving the selectivity and sensitivity of colorimetric cation sensors. The results of this study will facilitate the designing of organic materials whose certain properties can be enhanced through precise control of the materials’ chemical hybridization by simple functional end-group manipulation.

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Xie, Puhui, Fengqi Guo, Changshan Li, and Yue Xiao. "A new chemosensor based on rhodamine 101 hydrazone for Cu (II) in the red region." Canadian Journal of Chemistry 89, no. 11 (November 2011): 1364–69. http://dx.doi.org/10.1139/v11-111.

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A new chemosensor based on the spirolactam form of rhodamine 101 hydrazone (III) is found to exhibit a reversible colorimetric response toward Cu2+ in aqueous solutions in a selective, sensitive and rapid manner because of a formation of a Cu(II)-III complex. The dominating absorption maximum at 584 nm is uniquely red-shifted among rhodamine chemosensors toward Cu2+. The fluorescence of III can be detected in a low concentration of Cu2+. The results revealed that III is a good colorimetric sensor to Cu2+ in the red region.

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Denton, Jerod S., F. V. McCann, and J. C. Leiter. "CO2 chemosensitivity in Helix aspersa: three potassium currents mediate pH-sensitive neuronal spike timing." American Journal of Physiology-Cell Physiology 292, no. 1 (January 2007): C292—C304. http://dx.doi.org/10.1152/ajpcell.00172.2006.

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Elevated levels of carbon dioxide increase lung ventilation in Helix aspersa. The hypercapnic response originates from a discrete respiratory chemosensory region in the dorsal subesophageal ganglia that contains CO2-sensitive neurons. We tested the hypothesis that pH-dependent inhibition of potassium channels in neurons in this region mediated the chemosensory response to CO2. Cells isolated from the dorsal subesophageal ganglia retained CO2 chemosensitivity and exhibited membrane depolarization and/or an increase in input resistance during an acid challenge. Isolated somata expressed two voltage-dependent potassium channels, an A-type and a delayed-rectifier-type channel ( IKA and IKDR). Both conductances were inhibited during hypercapnia. The pattern of voltage dependence indicated that IKA was affected by extracellular or intracellular pH, but the activity of IKDR was modulated by extracellular pH only. Application of inhibitors of either channel mimicked many of the effects of acidification in isolated cells and neurons in situ. We also detected evidence of a pH-sensitive calcium-activated potassium channel ( IKCa) in neurons in situ. The results of these studies support the hypothesis that IKA initiates the chemosensory response, and IKDR and IKCa prolong the period of activation of CO2-sensitive neurons. Thus multiple potassium channels are inhibited by acidosis, and the combined effect of pH-dependent inhibition of these channels enhances neuronal excitability and mediates CO2 chemosensory responses in H. aspersa. We did not find a single “chemosensory channel,” and the chemosensitive channels that we did find were not unique in any way that we could detect. The protein “machinery” of CO2 chemosensitivity is probably widespread among neurons, and the selection process whereby a neuron acts or does not act as a respiratory CO2 chemosensor probably depends on the resting membrane potential and synaptic connectivity.

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Matmin, Juan, Nur Fatiha Ghazalli, Fazira Ilyana Abdul Razak, Hendrik O. Lintang, and Mohamad Azani Jalani. "Supramolecular Interactions in Aromatic Structures for Non-Optical and Optical Chemosensors of Explosive Chemicals." Solid State Phenomena 317 (May 2021): 202–7. http://dx.doi.org/10.4028/www.scientific.net/ssp.317.202.

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The scientific investigation based on the molecular design of aromatic compounds for high-performance chemosensor is challenging. This is because their multiplex interactions at the molecular level should be precisely determined before the desired compounds can be successfully used as sensing materials. Herein, we report on the molecular design of chemosensors based on aromatic structures of benzene as the organic motif of benzene-1,3,5-tricarboxamides (BTA), as well as the benzene pyrazole complexes (BPz) side chain, respectively. In the case of BTA, the aromatic benzene acts as the centre to allow the formation of π–π stacking for one-dimensional materials having rod-like arrangements that are stabilized by threefold hydrogen bonding. We found that when nitrate was applied, the rod-like BTA spontaneously formed into a random aggregate due to the deformation of its hydrogen bonding to form inactive nitroso groups for non-optical sensing capability. For the optical chemosensor, the aromatic benzene is decorated as a side-chain of BPz to ensure that cage-shaped molecules make maximum use of their centre providing metal-metal interactions for fluorescence-based sensing materials. In particular, when exposed to benzene, Cu-BPz displayed a blue-shift of its original emission band from 616 to 572 nm (Δ = 44 nm) and emitted bright orange to green emission colours. We also observe a different mode of fluorescence-based sensing materials for Au-BPz, which shows a particular quenching mechanism resulting in 81% loss of its original intensity on benzene exposure to give less red-orange emission (λ = 612 nm). The BTA and BPz synthesized are promising high-performance supramolecular chemosensors based on the non-optical and optical sensing capability of a particular interest analyte.

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Persat, Alexandre, Yuki F. Inclan, Joanne N. Engel, Howard A. Stone, and Zemer Gitai. "Type IV pili mechanochemically regulate virulence factors inPseudomonas aeruginosa." Proceedings of the National Academy of Sciences 112, no. 24 (June 3, 2015): 7563–68. http://dx.doi.org/10.1073/pnas.1502025112.

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Bacteria have evolved a wide range of sensing systems to appropriately respond to environmental signals. Here we demonstrate that the opportunistic pathogenPseudomonas aeruginosadetects contact with surfaces on short timescales using the mechanical activity of its type IV pili, a major surface adhesin. This signal transduction mechanism requires attachment of type IV pili to a solid surface, followed by pilus retraction and signal transduction through the Chp chemosensory system, a chemotaxis-like sensory system that regulates cAMP production and transcription of hundreds of genes, including key virulence factors. Like other chemotaxis pathways, pili-mediated surface sensing results in a transient response amplified by a positive feedback that increases type IV pili activity, thereby promoting long-term surface attachment that can stimulate additional virulence and biofilm-inducing pathways. The methyl-accepting chemotaxis protein-like chemosensor PilJ directly interacts with the major pilin subunit PilA. Our results thus support a mechanochemical model where a chemosensory system measures the mechanically induced conformational changes in stretched type IV pili. These findings demonstrate thatP. aeruginosanot only uses type IV pili for surface-specific twitching motility, but also as a sensor regulating surface-induced gene expression and pathogenicity.

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Rani, Poonam, Kashmiri Lal, and Rahul Shrivastava. "Tris-Triazole Based Chemosensors for Selective Sensing of Pb2+ Ions." Asian Journal of Chemistry 31, no. 11 (September 28, 2019): 2443–47. http://dx.doi.org/10.14233/ajchem.2019.22076.

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A series of novel tris-trizole based neutral chemosensors (4a-c) have been synthesized via click reaction and characterized by various spectral techniques. All the synthesized triazoles were evaluated for their ion binding properties towards various cations (Cu2+, Zn2+, Ca2+, Co2+, Cd2+, Hg2+, Pb2+ and Ni2+) by UV-visible titration experiments. It was observed that the addition of Pb2+ ions to compound 4a led to significant changes in UV-visible spectrum and a new UV band was observed at 262 nm. Further, the Job′s plot confirmed the formation of 1:1 complex between compound 4a and Pb2+. The synthesized chemosensor selectively sense Pb2+ ions in preference to other cations like Cu2+, Zn2+, Ca2+, Co2+, Cd2+, Hg2+, Pb2+ and Ni2+.

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Hu, Yun, Aiqian Chen, Zhuo Kong, and Demeng Sun. "A Reversible Colorimetric and Fluorescence “Turn-Off” Chemosensor for Detection of Cu2+ and Its Application in Living Cell Imaging." Molecules 24, no. 23 (November 25, 2019): 4283. http://dx.doi.org/10.3390/molecules24234283.

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Dual-function chemosensors that combine the capability of colorimetric and fluorimetric detection of Cu2+ are still relatively rare. Herein, we report that a 3-hydroxyflavone derivative (E)-2-(4-(dimethylamino)styryl)-3-hydroxy-4H-chromen-4-one (4), which is a red-emitting fluorophore, could serve as a reversible colorimetric and fluorescence “turn-off” chemosensor for the detection of Cu2+. Upon addition of Cu2+ to 4 in neutral aqueous solution, a dramatic color change from yellow to purple-red was clearly observed, and its fluorescence was markedly quenched, which was attributed to the complexation between the chemosensor and Cu2+. Conditions of the sensing process had been optimized, and the sensing studies were performed in a solution of ethanol/phosphate buffer saline (v/v = 3:7, pH = 7.0). The sensing system exhibited high selectivity towards Cu2+. The limit of naked eye detection of Cu2+ was determined at 8 × 10−6 mol/L, whereas the fluorescence titration experiment showed a detection limit at 5.7 × 10−7 mol/L. The complexation between 4 and Cu2+ was reversible, and the binding constant was found to be 3.2 × 104 M−1. Moreover, bioimaging experiments showed that 4 could penetrate the cell membrane and respond to the intracellular changes of Cu2+ within living cells, which indicated its potential for biological applications.

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Zeußel, Lisa, Carlos Aziz, Andreas Schober, and Sukhdeep Singh. "pH-Dependent Selective Colorimetric Detection of Proline and Hydroxyproline with Meldrum’s Acid-Furfural Conjugate." Chemosensors 9, no. 12 (December 4, 2021): 343. http://dx.doi.org/10.3390/chemosensors9120343.

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Activated 2-furfural gives intense color formation when reacted with amines, due to a ring opening reaction cascade that furnishes a conjugated molecular system. Unique colorimetric characteristic of this reaction makes it an interesting candidate for developing chemosensors operating in visible range. Among many activated 2-furfural derivatives, Meldrum’s acid furfural conjugate (MAFC) recently gained significant interest as colorimetric chemosensor. MAFC has been explored as selective chemosensor for detecting amines in solution, secondary amines on polymer surfaces and even nitrogen rich amino acids (AA) in aqueous solution. In this work, the pH dependency of MAFC-AA reaction is explored. It was found that proline gives an exceptionally fast colored reaction at pH 11, whereas at other pHs, no naked eye color product formation was observed. The reaction sequence including ring opening reaction upon nucleophilic addition of cyclic amine of proline resulting in a conjugated triene was confirmed by NMR titrations. The highly pH dependent reaction can e.g., potentially be used to detect proline presence in biological samples. An even more intense color formation takes place in the reaction of natural proline derivative 4-hydroxyproline. The detection limit of proline and 4-hydroxyproline with MAFC solution was found to be 11 µM and 6 µM respectively.

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Dethier, V. G. "FOOD-FINDING BY POLYPHAGOUS ARCTIID CATERPILLARS LACKING ANTENNAL AND MAXILLARY CHEMORECEPTORS." Canadian Entomologist 125, no. 1 (February 1993): 85–92. http://dx.doi.org/10.4039/ent12585-1.

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AbstractPatterns of locomotion of arctiid caterpillars, Diacrisia virginica Fabr., deprived of all external chemosensory organs were recorded in a field where there was patchy distribution of two of the most favored food plants, Plantago major L. and Taraxacum officinale Walker, on a background of grass and mixed forbs. Each track traced in the field was retraced on a digitizing tablet from its point of origin in the center of a circle of 30 cm radius to the circumference. The length of the path was a measure of tortuosity. The patterns of paths followed by normal, antennectomized, maxillectomized, and antennectomized + maxillectomized larvae were compared. No differences in meander were found. The ability of larvae of each class to locate, discriminate among, and feed upon food plants was tested in field-plot tests and cafeteria tests. Different degrees of chemosensory deprivation did not affect ability to locate and begin feeding on plants but did impair ability to discriminate among species. Execution of normal patterns of meandering by chemosensorily deprived larvae and successful encounters with food plants support the hypothesis that food-related search behavior by this species of caterpillar is neither initiated nor steered by chemical stimuli provided by food plants.

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Zhou, Wen, and Denise Chen. "Entangled chemosensory emotion and identity: Familiarity enhances detection of chemosensorily encoded emotion." Social Neuroscience 6, no. 3 (June 2011): 270–76. http://dx.doi.org/10.1080/17470919.2010.523537.

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Lintang, Hendrik Oktendy, Nur Fatiha Ghazalli, and Leny Yuliati. "Supramolecular Phosphorescent Trinuclear Copper(I) Pyrazolate Complexes for Vapochromic Chemosensors of Ethanol." Indonesian Journal of Chemistry 17, no. 2 (July 31, 2017): 191. http://dx.doi.org/10.22146/ijc.22553.

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We highlight that by using supramolecular single crystals of phosphorescent trinuclear copper(I) pyrazolate complexes with different molecular structures (2A-E), vapochromic chemosensors were successfully designed for sensing ethanol with high sensing capability. These complexes 2A-E were synthesized from non-side chain, 3,5-dimethyl, 3,5-bis(trifluoromethyl), 3,5-diphenyl and 4-(3,5-dimethoxybenzyl)-3,5-dimethyl pyrazole ligands (1A-E) in 83, 97, 99, 88 and 85% yields, respectively. All complexes showed emission bands centered at 553, 584, 570 and 616 nm upon an excitation at 280 nm for complexes 2A-C,E, respectively and 642 nm upon an excitation at 321 nm for complex 2D with lifetime in microseconds, indicating a large Stoke shift for phosphorescent compounds. These emission spectra were in good agreement with their colors from green to red upon exposure to a UV lamp with an excitation at 254 nm in dark room. Upon exposure to ethanol in 5 min, quenching, photoinduced energy transfer and shifting of emission intensities were observed for chemosensors 2A-C, 2D and 2E, respectively. Interestingly, chemosensor 2E only showed completely and autonomously recovery of its original emission intensity. Such novel finding in sensing capability might be caused by a weak intermolecular hydrogen bonding interaction of ethanol to oxygen atoms at dimethoxybenzyl side-chains of the pyrazole ring.

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Bai, Liping, Yuhang Xu, Guang Li, Shuhui Tian, Leixuan Li, Farong Tao, Aixia Deng, Shuangshuang Wang, and Liping Wang. "A Highly Selective Turn-on and Reversible Fluorescent Chemosensor for Al3+ Detection Based on Novel Salicylidene Schiff Base-Terminated PEG in Pure Aqueous Solution." Polymers 11, no. 4 (March 27, 2019): 573. http://dx.doi.org/10.3390/polym11040573.

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The development of highly selective and sensitive chemosensors for Al3+ detection in pure aqueous solution is still a significant challenge. In this work, a novel water-soluble polymer PEGBAB based on salicylidene Schiff base has been designed and synthesized as a turn-on fluorescent chemosensor for the detection of Al3+ in 100% aqueous solution. PEGBAB exhibited high sensitivity and selectivity to Al3+ over other competitive metal ions with the detection limit as low as 4.05 × 10−9 M. PEGBAB displayed high selectivity to Al3+ in the pH range of 5–10. The fluorescence response of PEGBAB to Al3+ was reversible in the presence of ethylenediaminetetraacetic acid (EDTA). Based on the fluorescence response, an INHIBIT logic gate was constructed with Al3+ and EDTA as two inputs. Moreover, test strips based on PEGBAB were fabricated facilely for convenient on-site detection of Al3+.

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Kaur, Sukhdeep, and Subodh Kumar. "Photoactive chemosensors 4: a Cu2+ protein cavity mimicking fluorescent chemosensor for selective Cu2+ recognition." Tetrahedron Letters 45, no. 26 (June 2004): 5081–85. http://dx.doi.org/10.1016/j.tetlet.2004.04.185.

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Петроченкова, Н. В., Т. Б. Емелина, and А. Г. Мирочник. "Механизм люминесцентного хемосенсорного отклика в хелатах европия(III)." Оптика и спектроскопия 130, no. 3 (2022): 428. http://dx.doi.org/10.21883/os.2022.03.52174.2526-21.

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There were studied the luminescent chemosensory properties of Eu(III) carboxylatodibenzoylmethanates with acetic and acrylic acids while the interaction with ammonia vapors. Quantitative measurements of the optical response showed that with an increase in the analyte concentration in the range of 3-330 ppm, a linear increase in the luminescence intensity of europium(III) is observed. The reversibility of the luminescent response was established, the limit of detection of ammonia was 3 ppm. The mechanism of the optical effect is revealed by the method of quantum chemical modeling: the interaction of ammonia with the sensor leads to the formation of a rigid structural fragment of H2O–NH3, which blocks the quenching effect of high-frequency OH vibrations on luminescence. The studied chemosensors have high sensitivity and selectivity and, thus, can be promising for creating ammonia detection sensors for food safety control and environmental monitoring.

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Udhayakumari, Duraisamy. "Various Sensing Mechanisms for the Design of Naphthalimide based Chemosensors Emerging in Recent Years." Recent Innovations in Chemical Engineering (Formerly Recent Patents on Chemical Engineering) 13, no. 4 (June 2, 2020): 262–89. http://dx.doi.org/10.2174/2405520413666200217125754.

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In the design of novel fluorescent chemosensors, investigation of new sensing mechanisms between recognition and signal reporting units is of increasing interest. In recent years, a smart chemosensor probe containing a 1,8-naphthalimide moiety could be developed as a fluorescent and colorimetric sensor for toxic anions, metal ions, biomolecules, nitroaromatics, and acids and be further applied to monitor the relevant biological applications. In this field, several problems and challenges still exist. This critical review is mainly focused on various sensing mechanisms that have emerged in the past few years, such as Photo-Induced Electron Transfer (PET), Intramolecular Charge Transfer (ICT), Fluorescence Resonance Energy Transfer (FRET), Excited-State Intramolecular Proton Transfer (ESIPT), hydrogen bonding and displacement approach. The review concludes with some current and future perspectives, including the use of the naphthalimides for sensing anions, metal ions, biomolecules, nitroaromatics and acids and their potential uses in various fields.

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Rodrigues, João M. M., Andreia S. F. Farinha, Zhi Lin, José A. S. Cavaleiro, Augusto C. Tome, and Joao P. C. Tome. "Phthalocyanine-Functionalized Magnetic Silica Nanoparticles as Anion Chemosensors." Sensors 21, no. 5 (February 26, 2021): 1632. http://dx.doi.org/10.3390/s21051632.

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Anionic species are one of the most common pollutants in residual and freshwaters. The presence of anthropogenic anions in water drastically increases the toxicity to living beings. Here, we report the preparation of a new optical active material based on tri(tosylamino)phthalocyanines grafted to ferromagnetic silica nanoparticles for anion detection and removal. The new unsymmetrical phthalocyanines (Pcs) proved to be excellent chemosensors for several anions (AcO−, Br−, Cl−, CN−, F−, H2PO4−, HSO4−, NO2−, NO3−, and OH−) in dimethyl sulfoxide (DMSO). Furthermore, the Pcs were grafted onto magnetic nanoparticles. The resulting novel hybrid material showed selectivity and sensitivity towards CN−, F−, and OH− anions in DMSO with limit of detection (LoD) of ≈4.0 µM. In water, the new hybrid chemosensor demonstrated selectivity and sensitivity for CN− and OH− anions with LoD of ≈0.2 µM. The new hybrids are easily recovered using a magnet, allowing recyclability and reusability, after acidic treatment, without losing the sensing proprieties.

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Kumar, Subodh, Pramila Kaur, and Sukhdeep Kaur. "Photoactive chemosensors. Part 1: A 9,10-anthraquinone and 2-aminothiophenol based Cu(II) selective chemosensor." Tetrahedron Letters 43, no. 6 (February 2002): 1097–99. http://dx.doi.org/10.1016/s0040-4039(01)02333-4.

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Iorio, Edward James, Yuefei Shao, Chao-Tsen Chen, Holger Wagner, and W. Clark Still. "Sequence-Selective Peptide Detection by Small Synthetic Chemosensors Selected from an Encoded Combinatorial Chemosensor Library." Bioorganic & Medicinal Chemistry Letters 11, no. 13 (July 2001): 1635–38. http://dx.doi.org/10.1016/s0960-894x(01)00236-0.

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Sugiarto, Joana, Zayyani Trianti Fatmasari, Sugiyani Puji Lestari, and Bambang Purwono. "Chemosensor Strip from Kepok Banana Bracts Extract (Musa paradisiaca L.) for Detection of Tuna Freshness." Jurnal Kimia Sains dan Aplikasi 25, no. 3 (March 10, 2022): 108–15. http://dx.doi.org/10.14710/jksa.25.3.108-115.

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Anthocyanins as chemosensory compounds for amines have been tested in this study. Because anthocyanins are sensitive to pH changes, while amines have an alkaline nature, they can cause structural changes in anthocyanins, resulting in changes in the color of anthocyanins. The source of anthocyanins was the Kepok banana bracts (Musa paradisiaca L.), which were extracted using a mixture of ethanol:HCl 0.15% (3:2). The types of anthocyanin compounds were characterized using a UV-Vis spectrophotometer. The anthocyanin content obtained varied from 1.26 mg/100 g to 5.08 mg/100 g. The type of anthocyanin in the Kepok banana bracts was found as a cyanidin-3-rutinoside with maximum absorption at 513 nm at pH 1. The color of anthocyanin extract varied with changes in pH; it turned red in acid and faded in neutral solutions. The green color in the alkaline solution changes to brownish-yellow was associated with anthocyanin degradation. The color change at different pH indicates that banana bracts are regarded as a potential chemosensory compound to detect tuna freshness. The chemosensor was applied to a cellulose-based strip and exhibited a color change that corresponded to the increase in pH and was comparable to the results of the pH meter measurement. The structural changes of anthocyanin before and after the tuna freshness test were identified by the FTIR-ATR, indicating a change in the anthocyanin structure. Tuna freshness began to diminish after being stored for 12 and 24 hours at room temperature, marked by a color change of the paper strip to colorless and blackish gray.

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Steinritz, Dirk, Bernhard Stenger, Alexander Dietrich, Thomas Gudermann, and Tanja Popp. "TRPs in Tox: Involvement of Transient Receptor Potential-Channels in Chemical-Induced Organ Toxicity—A Structured Review." Cells 7, no. 8 (August 7, 2018): 98. http://dx.doi.org/10.3390/cells7080098.

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Chemicals can exhibit significant toxic properties. While for most compounds, unspecific cell damaging processes are assumed, a plethora of chemicals exhibit characteristic odors, suggesting a more specific interaction with the human body. During the last few years, G-protein-coupled receptors and especially chemosensory ion channels of the transient receptor potential family (TRP channels) were identified as defined targets for several chemicals. In some cases, TRP channels were suggested as being causal for toxicity. Therefore, these channels have moved into the spotlight of toxicological research. In this review, we screened available literature in PubMed that deals with the role of chemical-sensing TRP channels in specific organ systems. TRPA1, TRPM and TRPV channels were identified as essential chemosensors in the nervous system, the upper and lower airways, colon, pancreas, bladder, skin, the cardiovascular system, and the eyes. Regarding TRP channel subtypes, A1, M8, and V1 were found most frequently associated with toxicity. They are followed by V4, while other TRP channels (C1, C4, M5) are only less abundantly expressed in this context. Moreover, TRPA1, M8, V1 are co-expressed in most organs. This review summarizes organ-specific toxicological roles of TRP channels.

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Yang, Yining, Xiaodong Zhou, Ruitao Dong, Yanwei Wang, Zichao Li, Yun Xue, and Qun Li. "A Highly Selective and Sensitive Nano-Silver sol Sensor for Hg2+ and Fe3+: Green Preparation and Mechanism." Polymers 14, no. 18 (September 7, 2022): 3745. http://dx.doi.org/10.3390/polym14183745.

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The development of highly selective and highly sensitive nanometer colorimetric chemical sensors is an urgent requirement in the immediate detection of heavy metal ions. In this work, silver-nanoparticle (Ag NPs)-based chemosensors were prepared by a simple and green method, in which the silver nitrate, carboxymethyl cellulose sodium (CMS) and Polyvinylpyrrolidone (PVP), and glucose are used as the silver source, double stabilizer and green reductant, respectively. The obtained colloidal CMS/PVP-Ag NPs showed a high dispersibility and stability, and creating a high selectivity and sensitivity to detect Hg2+ and Fe3+ with remarkable and rapid color variation. Low limits of detection (LOD) of 7.1 nM (0–20 μM) and 15.2 nM (20–100 μM) for Hg2+ and 3.6 nM for Fe3+ were achieved. More importantly, the CMS/PVP-Ag NPs has a high sensitivity even in a complex system with multiple heavy ions, the result of the practical ability to detect Hg2+ and Fe3+ in tap water and seawater reached a rational range of 98.33~104.2% (Hg2+) and 98.85~104.80% (Fe3+), indicating the great potential of the as-prepared nanocomposites colorimetric chemosensor for practical applications.

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Sahu, Sutapa, Yeasin Sikdar, Riya Bag, Javier Cerezo, José P. Cerón-Carrasco, and Sanchita Goswami. "Turn on Fluorescence Sensing of Zn2+ Based on Fused Isoindole-Imidazole Scaffold." Molecules 27, no. 9 (April 30, 2022): 2859. http://dx.doi.org/10.3390/molecules27092859.

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Optical chemosensors caused a revolution in the field of sensing due to their high specificity, sensitivity, and fast detection features. Imidazole derivatives have offered promising features in the literature as they bear suitable donor/acceptor groups for the selective analytes in the skeleton. In this work, an isoindole-imidazole containing a Schiff base chemosensor (1-{3-[(2-Diethylamino-ethylimino)-methyl]-2-hydroxy-5-methyl-phenyl}-2H-imidazo[5,1-a]isoindole-3,5-dione) was designed and synthesized. The complete sensing phenomena have been investigated by means of UV-Vis, fluorescence, lifetime measurement, FT-IR, NMR and ESI-MS spectroscopic techniques. The optical properties of the synthesized ligand were investigated in 3:7 HEPES buffer:DMSO medium and found to be highly selective and sensitive toward Zn2+ ion through a fluorescence turn-on response with detection limit of 0.073 μm. Furthermore, this response is effective in gel form also. The competition studies reveal that the response of the probe for Zn2+ ion is unaffected by other relevant metal ions. The stoichiometric binding study was performed utilizing Job’s method which indicated a 1:1 sensor–Zn2+ ensemble. Computational calculations were performed to pinpoint the mechanism of sensing.

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Schulp, A. S., E. W. A. Mulder, and K. Schwenk. "Did mosasaurs have forked tongues?" Netherlands Journal of Geosciences 84, no. 3 (September 2005): 359–71. http://dx.doi.org/10.1017/s0016774600021144.

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AbstractEver since the first mosasaur restorations were published, these extinct marine reptiles have been pictured with either notched, forked or undivided tongues. Here, we present an overview of existing iconography, a review of the previous literature, and we discuss how best to reconstruct tongue form in mosasaurs. Despite disagreement about their precise phylogenetic position, most authors consider mosasaurs members of the Varanoidea, derived anguimorphans including Helodermatidae, Varanidae, Lanthanotus and probably snakes. All anguimorphans share a diploglossan (two-part) tongue, in which the foretongue is derived and modified into a highly protrusible chemosensor, while the hindtongue is plesiomorphic, retaining well-developed papillae, mucocytes and robust posterior lobes. We suggest that mosasaurs had a diploglossan tongue that remained in a relatively underived state. The form of the tongue would probably have been most like modern Heloderma or Lanthanotus with a protrusible chemosensory foretongue and a plesiomorphic, papillose hindtongue. Such a tongue is consistent with well-developed vomeronasal chemoreception through tongue-flicking, with the retention of the ancestral function of hyolingual food transport and swallowing following jaw-prehension of prey. The presence of paired fenestrae in the palate associated with the vomers, as well as the presence of pterygoid teeth are in accordance with such a tongue form in mosasaurs.

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Perdana, Fitra, Karna Wijaya, and Ria Armunanto. "Studi Teoritis Senyawa Turunan Kalkon Hidroksi Sebagai Sensor Kimia Berbagai Anion." Jurnal Kimia Riset 3, no. 2 (March 4, 2019): 95. http://dx.doi.org/10.20473/jkr.v3i2.10425.

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AbstrakStudi secara teoritis telah dilakukan untuk mempelajari interaksi senyawa turunan kalkon hidroksi (CH) sebagai sensor kimia dengan anion F-, Cl-, Br-, CN-, CH3COO-, dan NO3-. Penelitian ini bertujuan untuk memodelkan struktur molekul senyawa turunan kalkon hidroksi (CH) dan sifat sensornya serta model interaksinya dengan anion dengan metode DFT. Hasil optimasi geometri menunjukkan terjadinya pemanjangan ikatan O-H sebesar 0,63-0,85 Å dengan adanya anion F-, CN-, and CH3COO-. Hal ini mengindikasikan terjadinya deprotonasi sensor kalkon hidroksi (CH) oleh anion. Sedangkan interaksi sensor kalkon hidroksi (CH) dengan anion Cl-, Br-, dan NO3- hanya berupa ikatan hidrogen dengan pemanjangan ikatan O-H sebesar 0,08-0,46 Å. Sensor kalkon hidroksi (CH) yang mengalami deprotonasi memiliki energi interaksi yang lebih besar yaitu -209,37 – -424,06 kJ/mol dibandingkan sensor yang hanya membentuk ikatan hidrogen yaitu -98,60 – -125,59 kJ/mol. Sensor yang mengalami deprotonasi mengakibatkan turunnya selisih energi HOMO-LUMO dari -3,94 – -4,06 eV menjadi -2,62 – -2,75 eV.Kata kunci: sensor kimia, kalkon hidroksi, anion, DFT AbstractTheoretical study had been carried out to investigate interaction between hydroxy chalcone derivatives (CH) as chemosensors with F-, Cl-, Br-, CN-, CH3COO-, and NO3- anions. This study was aimed to design molecular structures of chemosensor hydroxy chalcone (CH) properties for the anions and their interaction models with DFT method. The result of geometry optimization showed 0,63-0,85 Å O-H bond elongation of the hydroxy chalcone was occured by F-, CN-, and CH3COO-. It was indicated deprotonation of sensor hydroxy chalcone (CH) by anions. Where as the interaction of the hydroxy chalcone (CH) with Cl-, Br-, and NO3- just formed an hydrogen bond with 0,08-0,46 Å O-H bond elongation. Deprotonized sensor hydroxy chalcone (CH) had more energy change of interaction -209,37– -424,06 kJ/mol than sensor which just formed the hydrogen bond -98,60 – -125,59 kJ/mol. Deprotonized sensor caused reduction of the difference of HOMO-LUMO energy from - 3,94 – -4,06 eV to -2,62 – -2,75 eV.Keywords: chemosensor, hydroxy chalcone, anion, DFT

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Steullet, Pascal, Omar Dudar, Tanya Flavus, Min Zhou, and Charles D. Derby. "Selective ablation of antennular sensilla on the Caribbean spiny lobsterPanulirus argussuggests that dual antennular chemosensory pathways mediate odorant activation of searching and localization of food." Journal of Experimental Biology 204, no. 24 (December 15, 2001): 4259–69. http://dx.doi.org/10.1242/jeb.204.24.4259.

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SUMMARYIn spiny lobsters and other decapod crustaceans, odorant-mediated searching behavior patterns are driven primarily by chemosensory neurons in the antennules. Two groups of antennular chemosensory neurons can be distinguished on the basis of the sensilla that they innervate and their central projections: those that innervate the aesthetasc sensilla on the lateral flagella and project into the glomerularly organized olfactory lobes, and those that innervate other (i.e. non-aesthetasc) sensilla on both lateral and medial flagella and project into the stratified and non-glomerularly organized lateral antennular neuropils. By ablating different groups of antennular sensory neurons or sensilla, we examined the role of aesthetasc and non-aesthetasc chemosensory neurons in regulating local searching behavior of Caribbean spiny lobsters, Panulirus argus, for food (squid) in a low-flow environment. The results show that odorant-mediated activation of searching and localization of food under these conditions requires only a subset of functional antennular chemosensory neurons, since neither aesthetasc chemosensory neurons nor non-aesthetasc chemosensory neurons are by themselves necessary for these types of behavior. However, ablation of aesthetasc chemosensory neurons together with subsets of non-aesthetasc chemosensory neurons from either the medial or lateral flagella impairs the ability of lobsters to locate the food. This reveals a large degree of functional redundancy but also some complementary functions between aesthetasc and non-aesthetasc chemosensory neurons, and hence between these dual antennular chemosensory pathways, in odorant-mediated searching behavior of lobsters under these conditions.

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Tsuchiya, Sakura, Yuko Terada, Minami Matsuyama, Toyomi Yamazaki-Ito, and Keisuke Ito. "A new screening method for identifying chemosensory receptors responding to agonist." Bioscience, Biotechnology, and Biochemistry 85, no. 6 (March 9, 2021): 1521–25. http://dx.doi.org/10.1093/bbb/zbab035.

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ABSTRACT Humans sense taste and smell of various chemical substances through approximately 430 chemosensory receptors. The overall picture of ligand–chemosensory receptor interactions has been partially clarified because of numerous interactions. This study presents a new method that enables a rapid and simple screening of chemosensory receptors. It would be useful for identifying chemosensory receptors activated by taste and odor substances.

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Schwartz, Mathieu, Valentin Boichot, Stéphane Fraichard, Mariam Muradova, Patrick Senet, Adrien Nicolai, Frederic Lirussi, et al. "Role of Insect and Mammal Glutathione Transferases in Chemoperception." Biomolecules 13, no. 2 (February 8, 2023): 322. http://dx.doi.org/10.3390/biom13020322.

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Glutathione transferases (GSTs) are ubiquitous key enzymes with different activities as transferases or isomerases. As key detoxifying enzymes, GSTs are expressed in the chemosensory organs. They fulfill an essential protective role because the chemosensory organs are located in the main entry paths of exogenous compounds within the body. In addition to this protective function, they modulate the perception process by metabolizing exogenous molecules, including tastants and odorants. Chemosensory detection involves the interaction of chemosensory molecules with receptors. GST contributes to signal termination by metabolizing these molecules. By reducing the concentration of chemosensory molecules before receptor binding, GST modulates receptor activation and, therefore, the perception of these molecules. The balance of chemoperception by GSTs has been shown in insects as well as in mammals, although their chemosensory systems are not evolutionarily connected. This review will provide knowledge supporting the involvement of GSTs in chemoperception, describing their localization in these systems as well as their enzymatic capacity toward odorants, sapid molecules, and pheromones in insects and mammals. Their different roles in chemosensory organs will be discussed in light of the evolutionary advantage of the coupling of the detoxification system and chemosensory system through GSTs.

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Devaraj, S., D. Saravanakumar, and M. Kandaswamy. "Dual responsive chemosensors for anion and cation: Synthesis and studies of selective chemosensor for F− and Cu(II) ions." Sensors and Actuators B: Chemical 136, no. 1 (February 2009): 13–19. http://dx.doi.org/10.1016/j.snb.2008.11.018.

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Zhu, Xiaoyan, Qiling Yu, Xingyu Gan, Liwen Song, Kaipeng Zhang, Tongtong Zuo, Junjie Zhang, Ying Hu, Qi Chen, and Bingzhong Ren. "Transcriptome Analysis and Identification of Chemosensory Genes in Baryscapus dioryctriae (Hymenoptera: Eulophidae)." Insects 13, no. 12 (November 29, 2022): 1098. http://dx.doi.org/10.3390/insects13121098.

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Baryscapus dioryctriae is a pupal endoparasitoid of many Pyralidae pests and has been used as a biocontrol agent against insect pests that heavily damage the cone and seed of the Korean pine. The olfactory system of wasps plays an essential role in sensing the chemical signals during their foraging, mating, host location, etc., and the chemosensory genes are involved in detecting and transducing these signals. Many chemosensory genes have been identified from the antennae of Hymenoptera; however, there are few reports on the chemosensory genes of Eulophidae wasps. In this study, the transcriptome databases based on ten different tissues of B. dioryctriae were first constructed, and 274 putative chemosensory genes, consisting of 27 OBPs, 9 CSPs, 3 NPC2s, 155 ORs, 49 GRs, 23 IRs and 8 SNMPs genes, were identified based on the transcriptomes and manual annotation. Phylogenetic trees of the chemosensory genes were constructed to investigate the orthologs between B. dioryctriae and other insect species. Additionally, twenty-eight chemosensory genes showed female antennae- and ovipositor-biased expression, which was validated by RT-qPCR. These findings not only built a molecular basis for further research on the processes of chemosensory perception in B. dioryctriae, but also enriched the identification of chemosensory genes from various tissues of Eulophidae wasps.

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Rahaman, Fazlur, Prabhat Gautam, Priti Gupta, and Subrata Mondal. "A Simple and Efficient Schiff Base Derived Chemosensor for Selective Detection of Fluoride Ion." Journal of University of Shanghai for Science and Technology 23, no. 09 (September 14, 2021): 646–55. http://dx.doi.org/10.51201/jusst/21/09551.

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A new thiazole substituted chemosensor 1 has been designed and synthesized for selective detection of fluoride ions. The chemosensor 1 was characterized by 1H NMR and 13C NMR. The absorption studies of chemosensor in DMF exhibits two peaks at 283 nm and 327 nm. The anion sensing behaviour of chemosensor 1 for various anions (I-, Cl-, Br-, NO3-, HSO4-, PF6-, ClO4-) in DMF were investigated by UV-vis spectroscopy. Chemosensor 1 exhibited high degree of selectivity for fluoride ions over other anions. A good linearity in the range of 16-133 μM with 6.12 μM limit of detection value (LOD) was observed.

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Kang, Z. W., F. H. Liu, R. P. Pang, W. B. Yu, X. L. Tan, Z. Q. Zheng, H. G. Tian, and T. X. Liu. "The identification and expression analysis of candidate chemosensory genes in the bird cherry-oat aphid Rhopalosiphum padi (L.)." Bulletin of Entomological Research 108, no. 5 (December 4, 2017): 645–57. http://dx.doi.org/10.1017/s0007485317001171.

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AbstractThe bird cherry-oat aphid Rhopalosiphum padi (L.) is one of the most important wheat pests with polyphagia and autumn migrants. And, chemosensory genes were thought to play a key role in insect searching their hosts, food and mate. However, a systematic identification of the chemosensory genes in this pest has not been reported. Thus, in this study, we identified 14 odorant-binding proteins, nine chemosensory proteins, one sensory neuron membrane protein, 15 odorant receptors, 19 gustatory receptors and 16 ionotropic receptors from R. padi transcriptomes with a significantly similarity (E-value < 10−5) to known chemosensory genes in Acyrthosiphon pisum and Aphis gossypii. In addition, real-time quantitative polymerase chain reaction (RT-qPCR) was employed to determine the expression profiles of obtained genes. Among these obtained genes, we selected 23 chemosensory genes to analyze their expression patterns in different tissues, wing morphs and host plants. We found that except RpOBP1, RpOBP3, RpOBP4 and RpOBP5, the rest of the selected genes were highly expressed in the head with antennae compared with body without head and antennae. Besides that, the stimulation and depression of chemosensory genes by plant switch indicated that chemosensory genes might be involved in the plant suitability assessment. These results not only provide insights for the potential roles of chemosensory genes in plant search and perception of R. padi but also provide initial background information for the further research on the molecular mechanism of the polyphagia and autumn migrants of it. Furthermore, these chemosensory genes are also the candidate targets for pest management control in future.

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Rondoni, Gabriele, Alessandro Roman, Camille Meslin, Nicolas Montagné, Eric Conti, and Emmanuelle Jacquin-Joly. "Antennal Transcriptome Analysis and Identification of Candidate Chemosensory Genes of the Harlequin Ladybird Beetle, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae)." Insects 12, no. 3 (March 2, 2021): 209. http://dx.doi.org/10.3390/insects12030209.

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In predatory ladybirds (Coleoptera: Coccinellidae), antennae are important for chemosensory reception used during food and mate location, and for finding a suitable oviposition habitat. Based on NextSeq 550 Illumina sequencing, we assembled the antennal transcriptome of mated Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) males and females and described the first chemosensory gene repertoire expressed in this species. We annotated candidate chemosensory sequences encoding 26 odorant receptors (including the coreceptor, Orco), 17 gustatory receptors, 27 ionotropic receptors, 31 odorant-binding proteins, 12 chemosensory proteins, and 4 sensory neuron membrane proteins. Maximum-likelihood phylogenetic analyses allowed to assign candidate H. axyridis chemosensory genes to previously described groups in each of these families. Differential expression analysis between males and females revealed low variability between sexes, possibly reflecting the known absence of relevant sexual dimorphism in the structure of the antennae and in the distribution and abundance of the sensilla. However, we revealed significant differences in expression of three chemosensory genes, namely two male-biased odorant-binding proteins and one male-biased odorant receptor, suggesting their possible involvement in pheromone detection. Our data pave the way for improving the understanding of the molecular basis of chemosensory reception in Coccinellidae.

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Rombaux, Ph, C. Huart, and A. Mouraux. "Assessment of chemosensory function using electroencephalographic techniques." Rhinology journal 50, no. 1 (March 1, 2012): 13–21. http://dx.doi.org/10.4193/rhino11.126.

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Electroencephalographic techniques are widely used to provide an objective evaluation of the chemosensory function and to explore neural mechanisms related to the processing of chemosensory events. The most popular technique to evaluate brain responses to chemosensory stimuli is across trial time-domain averaging to reveal chemosensory event-related potentials (CSERP) embedded within the ongoing EEG. Nevertheless, this technique has a poor signal-to-noise ratio and cancels out stimulus-induced changes in the EEG signal that are not strictly phased-locked to stimulus onset. The fact that consistent CSERP are not systematically identifiable in healthy subjects currently constitutes a major limitation to the use of this technique for the diagnosis of chemosensory dysfunction. In this review, we will review the different techniques related to the recording and identification of CSERP, discuss some of their limitations, and propose some novel signal processing methods which could be used to enhance the signal-to-noise ratio of chemosensory event-related brain responses.

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Journal articles on the topic 'Chemosensori'

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