Chemosensors

15 pages, 9543 KB

Open AccessArticle

A Novel Electrochemiluminescent Biosensor Based on Nitrogen-Doped Graphyne for Ultrasensitive Kanamycin Residue Detection in Milk and Honey Samples

by Yuxuan Liu, Tianzeng Huang, Yang Chen, Gaowa Xing, Hongmei Cao and Daixin Ye

Chemosensors 2026, 14(3), 76; https://doi.org/10.3390/chemosensors14030076 - 23 Mar 2026

Viewed by 647

Abstract

A novel sensitive and selective electrochemiluminescence (ECL) sensor using nitrogen-doped graphyne as the platform was proposed for kanamycin (KAN) detection. First, nitrogen-doped graphyne nanomaterial (1N-GY) with high conductivity was synthesized using a high-energy ball milling method. Compared with ordinary graphyne, the addition of [...] Read more.

A novel sensitive and selective electrochemiluminescence (ECL) sensor using nitrogen-doped graphyne as the platform was proposed for kanamycin (KAN) detection. First, nitrogen-doped graphyne nanomaterial (1N-GY) with high conductivity was synthesized using a high-energy ball milling method. Compared with ordinary graphyne, the addition of nitrogen atoms can improve the conductivity of the material and reduce the electronic migration energy barrier. Then it was used as a substrate material of the ECL sensor, not only increasing the conductivity of the biosensor but also improving the sensitivity of the ECL sensor by providing more immobilization space for the luminescent probe of Nafion-coated mesoporous silica adsorbed Ru(bpy)₃²⁺ (mSiO₂@Nafion@Ru(bpy)₃²⁺). On this basis, mSiO₂@Nafion@Ru(bpy)₃²⁺ functionalized DNA probes were used as luminescent and capture probes to specifically recognize different concentrations of KAN to produce ECL signals. Under optimal conditions, the proposed ECL sensor exhibited good linearity (10⁻¹²–10⁻⁶ M KAN) and a low detection limit of 1.08 pM. The prepared biosensor with good stability and selectivity successfully detected KAN in honey and milk samples, with spiked recovery rates ranging from 98% to 111.79%. This method not only expands the application of 1N-GY as a novel graphitic material in ECL biosensors but also provides an effective way to check antibiotics in dairy products. Full article

(This article belongs to the Special Issue (Bio)Chemical Sensing in Real-World Applications—a Dedicated Issue for Young Researchers)

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47 pages, 2326 KB

Open AccessReview

Carbon Paste Electrodes for Antibiotic Electrochemical Quantification: State of the Art

by Daniela Partene, Iulia Gabriela David, Mihaela-Carmen Cheregi, Emilia-Elena Iorgulescu and Hassan Noor

Chemosensors 2026, 14(3), 75; https://doi.org/10.3390/chemosensors14030075 - 20 Mar 2026

Viewed by 1298

Abstract

Antibiotics are used primarily in human and veterinary medicine to treat various infections. They have also found applications in animal farms and aquaculture as growth promotors, with the aim of increasing food production. Their uncontrolled use can lead to increased bacterial resistance to [...] Read more.

Antibiotics are used primarily in human and veterinary medicine to treat various infections. They have also found applications in animal farms and aquaculture as growth promotors, with the aim of increasing food production. Their uncontrolled use can lead to increased bacterial resistance to antibiotics as well as other adverse effects. Unfortunately, these can reach and accumulate in the environment. Thus, their sensitive and selective detection from various matrices, using inexpensive and portable instruments, is becoming an increasing necessity. Electrochemical techniques are a viable alternative in this regard, and carbon paste electrodes (CPEs) present electrochemical and economic characteristics that recommend them as versatile devices for this purpose. Therefore, this paper is a comprehensive synthesis of the information presented in the last 10 years in the literature regarding CPEs developed for the analysis of antibiotics in different samples. Methods for obtaining different modified CPEs and their performances in detecting compounds belonging to different classes of antibiotics were discussed and priorities for future development were suggested. Through this review, researchers interested in the (electro)analysis of antibiotics will gain information about the advantages and limitations of using CPEs and the efforts made in the last decade to improve their performance. Full article

(This article belongs to the Special Issue Low-Cost Chemosensors for Applications in Environment, Health, Food, and Industry Process Control, 2nd Edition)

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5 pages, 186 KB

Open AccessEditorial

Electrochemical Sensors and Biosensors for Food, Environmental and Biomedical Analysis

by Diego Leoni Franco and Lucas Franco Ferreira

Chemosensors 2026, 14(3), 74; https://doi.org/10.3390/chemosensors14030074 - 20 Mar 2026

Viewed by 868

Abstract

The premise of electrochemical sensors and biosensors is based on a miniaturized device that can provide precise, highly reliable results with sensitivity and selectivity that is comparable to or even better than the current gold standards [...] Full article

(This article belongs to the Special Issue Electrochemical Sensors and Biosensors for Food, Environmental and Biomedical Analysis)

30 pages, 4355 KB

Open AccessArticle

Using Human Assessment and GC-MS to Identify Potential Use Cases for Evaluating Food Condition with Gas Sensor Systems

by Julian Joppich, Andreas Schütze and Christian Bur

Chemosensors 2026, 14(3), 73; https://doi.org/10.3390/chemosensors14030073 - 19 Mar 2026

Viewed by 693

Abstract

Technological solutions might be of great importance for reducing food waste. In the scope of this article, gas sensor systems for assessing the edibility of food have been studied, which can help to avoid food losses by suggesting consumption before spoilage or by [...] Read more.

Technological solutions might be of great importance for reducing food waste. In the scope of this article, gas sensor systems for assessing the edibility of food have been studied, which can help to avoid food losses by suggesting consumption before spoilage or by separating infected fruits from fresh ones. Several series of measurements with various foodstuffs were conducted to develop methods that enable the identification of possible use cases in which gas sensors could be used to assess food condition as well as methods to calibrate such sensor systems. This paper presents results for oranges as an important target for grocery stores. The fruit headspace was measured by gas sensors, reference data were acquired using human assessment (appearance, odor, edibility) and gas chromatography–mass spectrometry (GC-MS) analysis. Data evaluation shows correlations between the performance of individual sensors for a technical assessment of fruit condition with marker substances identified by GC-MS, e.g., limonene for damaged oranges. Models were derived that are, in general, able to quantify the edibility or to classify defects/mold, but limitations in the applicability/transferability, e.g., between orange varieties, were also identified. With the knowledge gained, important steps could be taken towards an application-oriented setup, and recommendations regarding the sensors used, food trained, and calibration methods applied are derived. Full article

(This article belongs to the Special Issue Applications of Electronic Nose (E-Nose) and Electronic Tongue (E-Tongue) in Food Quality)

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18 pages, 5263 KB

Open AccessArticle

TSNP-Ink on PDMS: A Flexible SERS Substrate for Damage-Free Agricultural Pesticide Detection

by Apinya Ketkong, Kheamrutai Thamaphat, Thana Sutthibutpong, Noppadon Nuntawong and Fueangfakan Chutrakulwong

Chemosensors 2026, 14(3), 72; https://doi.org/10.3390/chemosensors14030072 - 18 Mar 2026

Cited by 1 | Viewed by 824

Abstract

Sensitive and on-site detection of pesticide residues remains a critical challenge for food safety, particularly in developing regions where rapid screening tools are urgently needed. Herein, we report a flexible surface-enhanced Raman scattering (SERS) platform based on triangular silver nanoplates (TSNPs) integrated onto [...] Read more.

Sensitive and on-site detection of pesticide residues remains a critical challenge for food safety, particularly in developing regions where rapid screening tools are urgently needed. Herein, we report a flexible surface-enhanced Raman scattering (SERS) platform based on triangular silver nanoplates (TSNPs) integrated onto a polydimethylsiloxane (PDMS) substrate, enabling sensitive and conformal detection of paraquat residues on agricultural surfaces. TSNPs were synthesized via a seed-mediated photochemical growth method and formulated into a TSNP ink, which was directly deposited onto oxygen-plasma-treated and thiol-functionalized PDMS substrates. Owing to the highly anisotropic geometry and sharp edges of TSNPs, the flexible SERS substrate exhibits strong localized surface plasmon resonance (LSPR) enhancement and mechanically stable electromagnetic hot spots. Systematic optimization of TSNP optical absorbance revealed that uniform nanoplate distribution and optimal hotspot density were achieved at an absorbance of 2.0. The SERS performance was evaluated using rhodamine 6G under front-side and back-side illumination configurations, demonstrating good signal reproducibility and a detection limit of approximately 10⁻⁵ M. Notably, back-side illumination through the PDMS layer provided superior SERS responses due to improved optical transmission and light–matter interaction. The practical applicability was further demonstrated through back-side SERS detection of paraquat on aluminum foil as a model surface, achieving a lowest detectable concentration of 5 × 10⁻⁶ M, followed by damage-free detection on Chinese pear peels. This work highlights a reliable and nondestructive flexible SERS platform for on-site pesticide residue monitoring. Full article

(This article belongs to the Special Issue Spectroscopic Techniques for Chemical Analysis, 2nd Edition)

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24 pages, 7790 KB

Open AccessReview

Flexible Pressure Sensors from a Multidisciplinary Perspective: Principles, Material Selection and Application Expansion

by Lichao Liu, Huihui Zhu, Xuefeng Gu, Ping Hu, Yang Chen, Pengjia Qi and Kai Liu

Chemosensors 2026, 14(3), 71; https://doi.org/10.3390/chemosensors14030071 - 17 Mar 2026

Viewed by 1763

Abstract

As wearable electronic products have been integrated into daily life, flexible pressure sensors, which convert pressure into electrical signals, have become a research focus because of their cross-industry application potential. Despite an increasing number of related studies, the systematic integration of discussions on [...] Read more.

As wearable electronic products have been integrated into daily life, flexible pressure sensors, which convert pressure into electrical signals, have become a research focus because of their cross-industry application potential. Despite an increasing number of related studies, the systematic integration of discussions on sensing mechanisms, performance regulation, and multiscenario adaptability remains to be explored. In this paper, core sensing mechanisms such as piezoresistive, capacitive, piezoelectric, and triboelectric mechanisms are systematically reviewed; key performance indicators, including sensitivity, response time, and linearity, are analyzed; construction strategies for diverse substrates and conductive functional materials are explored; and applications in healthcare, human–computer interaction, and electronic skin are elaborated on. The aim of these analyses is to provide practical insights into the development and design of flexible pressure sensors, thus providing a useful reference for advancing these technologies and expanding their cross-domain use. Full article

(This article belongs to the Special Issue Advances in Electrochemical Sensors: Emerging Materials, Techniques, and Applications)

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22 pages, 7355 KB

Open AccessReview

Silicon-Compatible Semiconductor Gas Sensors

by Yanting Tang, Xinyi Chen, Huanhuan Zhang, Lanpeng Guo, Hua-Yao Li and Huan Liu

Chemosensors 2026, 14(3), 70; https://doi.org/10.3390/chemosensors14030070 - 17 Mar 2026

Viewed by 1769

Abstract

The growing demand for intelligent environmental monitoring is driving the advancement of high-performance, low-cost, and highly integrated gas sensors. Silicon-compatible semiconductor gas sensors provide a promising platform to achieve this goal by leveraging their compatibility with complementary metal–oxide semiconductor (CMOS) processes. The established [...] Read more.

The growing demand for intelligent environmental monitoring is driving the advancement of high-performance, low-cost, and highly integrated gas sensors. Silicon-compatible semiconductor gas sensors provide a promising platform to achieve this goal by leveraging their compatibility with complementary metal–oxide semiconductor (CMOS) processes. The established mass-manufacturing capabilities of micro-electromechanical systems (MEMS) and the high sensitivity and signal amplification characteristics of field effect transistors (FETs) in recent years have made the development of next-generation sensing devices feasible. In this review, we systematically summarize the latest advances in silicon-compatible gas sensors, with a focus on MEMS and FET technologies. We discuss their sensing mechanisms and performance optimization strategies, and further highlight the evolution of gas sensor technology toward on-chip intelligent olfactory systems that integrate sensing, computing, and storage capabilities. Full article

(This article belongs to the Special Issue Recent Advances in Low-Cost Chemical Sensor Technologies for Environmental Monitoring Applications)

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13 pages, 848 KB

Open AccessArticle

Environmental Monitoring of Celecoxib, Ketoprofen, and Meloxicam in Pharmaceutical Wastewater by SPE-Assisted Micellar Electrokinetic Chromatography

by Alhumaidi B. Alabbas and Sherif A. Abdel-Gawad

Chemosensors 2026, 14(3), 69; https://doi.org/10.3390/chemosensors14030069 - 13 Mar 2026

Viewed by 660

Abstract

The continuous discharge of pharmaceutical residues into aquatic environments has raised significant environmental concerns due to their persistence and incomplete removal during wastewater treatment. Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most frequently detected pharmaceutical contaminants in industrial effluents. In this study, a [...] Read more.

The continuous discharge of pharmaceutical residues into aquatic environments has raised significant environmental concerns due to their persistence and incomplete removal during wastewater treatment. Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most frequently detected pharmaceutical contaminants in industrial effluents. In this study, a sensitive and selective analytical method was developed for the simultaneous determination of ketoprofen (KTP), meloxicam (MEL), and celecoxib (CEL) in pharmaceutical wastewater using micellar electrokinetic chromatography (MEKC) combined with off-line solid-phase extraction (SPE). A high-volume SPE procedure (1000 mL sample) followed by evaporation and reconstitution provided a theoretical enrichment factor of approximately 10,000. Under optimised conditions, complete separation was achieved in less than 10 min. The method exhibited excellent linearity over a range of 0.5–20 µg/mL (r² > 0.999), with limits of detection in wastewater ranging from 14 to 18 ng/L. Accuracy and precision complied with ICH Q2(B) guidelines, and recoveries from spiked wastewater samples ranged from approximately 99% to 101%, indicating efficient extraction and minimal analyte loss. The validated method was successfully applied to real pharmaceutical wastewater samples, demonstrating its suitability for the routine monitoring of trace-level NSAIDs in complex industrial matrices. Full article

(This article belongs to the Special Issue Low-Cost Chemosensors for Applications in Environment, Health, Food, and Industry Process Control, 2nd Edition)

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23 pages, 3597 KB

Open AccessArticle

Enhanced Electrochemical Glucose Sensing via AuNP-Assisted Electrodeposition and Yeast Modification

by Teresė Kondrotaitė-Intė, Domas Pirštelis, Laisvidas Striška, Antanas Zinovičius, Inga Morkvėnaitė and Arūnas Ramanavičius

Chemosensors 2026, 14(3), 68; https://doi.org/10.3390/chemosensors14030068 - 12 Mar 2026

Viewed by 980

Abstract

This study investigates the combined effect of electrodeposited gold nanoparticles (AuNPs) and AuNP–polypyrrole (PPy)-modified Saccharomyces cerevisiae on electrochemical glucose sensing. AuNPs were deposited onto electrode surfaces by cyclic voltammetry, and the resulting interfaces were characterized using atomic force microscopy, cyclic voltammetry, and electrochemical [...] Read more.

This study investigates the combined effect of electrodeposited gold nanoparticles (AuNPs) and AuNP–polypyrrole (PPy)-modified Saccharomyces cerevisiae on electrochemical glucose sensing. AuNPs were deposited onto electrode surfaces by cyclic voltammetry, and the resulting interfaces were characterized using atomic force microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. AFM analysis confirmed increased surface roughness and height variability after deposition, indicating substantial restructuring of the electrode interface. Electrochemical measurements showed that AuNP deposition altered interfacial charge storage and transfer and increased the measured charge-transfer resistance. Glucose sensing was evaluated in a ferricyanide-mediated system using yeast layers with or without AuNP and PPy modification over a 0–60 mM concentration range. All configurations exhibited saturating, non-linear glucose responses described by Hill fitting. Among the evaluated yeast-modified electrodes, the AuNP–PPy modified yeast produced the strongest glucose-induced current increase and the best low-concentration performance, achieving a limit of detection of 0.540 mM, compared with 1.016 mM and 1.330 mM for single-modified layers and 3.360 mM for unmodified yeast. These results show that combining AuNP electrodeposition with AuNP–PPy yeast modification improves interfacial properties and enhances mediator-assisted electrochemical glucose sensing. Full article

(This article belongs to the Special Issue Recent Advances in Low-Cost Chemical Sensor Technologies for Environmental Monitoring Applications)

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14 pages, 2967 KB

Open AccessCommunication

A New Acridine-Based Fluorescent Sensor for the Detection of CN⁻

by Yiyuan Zhang, Chen Zhou, Jiaxin Li and Evgeny Kovtunets

Chemosensors 2026, 14(3), 67; https://doi.org/10.3390/chemosensors14030067 - 12 Mar 2026

Cited by 1 | Viewed by 737

Abstract

A novel acridine-based fluorescent sensor (Sensor ANT) for the highly selective and sensitive detection of cyanide ions (CN⁻) was rationally designed and synthesized via the conjugation reaction of acridine-9-amine with 3-nitrophenyl isothiocyanate. The sensing mechanism is triggered by the specific interaction [...] Read more.

A novel acridine-based fluorescent sensor (Sensor ANT) for the highly selective and sensitive detection of cyanide ions (CN⁻) was rationally designed and synthesized via the conjugation reaction of acridine-9-amine with 3-nitrophenyl isothiocyanate. The sensing mechanism is triggered by the specific interaction between exogenous CN⁻ and the hydrogen-bonding moieties within the sensor’s molecular framework, which induces a distinct fluorescence quenching response. Systematic titration experiments confirmed that Sensor ANT exhibits rapid response kinetics, excellent selectivity, and reliable qualitative/quantitative detection capabilities toward CN⁻. Complementary biocompatibility assays, including in vitro cellular imaging and in vivo zebrafish experiments, further verified the promising application potential of this sensor in practical and biological detection scenarios. The detection limit (DL) of Sensor ANT for CN⁻ was calculated to be 2.89 × 10⁻⁷ M, with a 1:1 binding stoichiometry and a binding constant of 1.95 × 10⁴ M⁻¹. These findings demonstrate that Sensor ANT represents a robust candidate for CN⁻ detection in environmental and biological systems. Full article

(This article belongs to the Special Issue Application of Luminescent Materials for Sensing, 2nd Edition)

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24 pages, 2944 KB

Open AccessReview

From Natural Pigments to Bioinspired Sensors: The Emerging Role of Melanins

by Elena Cassera, Anna Angeleri, Michela Sturini, Emanuele Ferrari and Andrea Capucciati

Chemosensors 2026, 14(3), 66; https://doi.org/10.3390/chemosensors14030066 - 10 Mar 2026

Viewed by 2384

Abstract

The growing demand for sustainable, biocompatible, and multifunctional sensing materials has intensified interest in melanin and its derivatives, including melanin-inspired polymers and composites. Melanin is a naturally occurring biopolymer whose intricate structure and diverse chemical composition give rise to a remarkable combination of [...] Read more.

The growing demand for sustainable, biocompatible, and multifunctional sensing materials has intensified interest in melanin and its derivatives, including melanin-inspired polymers and composites. Melanin is a naturally occurring biopolymer whose intricate structure and diverse chemical composition give rise to a remarkable combination of optical, electrical, and chemical properties. Key physicochemical characteristics, such as broadband optical absorption, hydration-dependent conductivity, redox activity, and metal ion coordination, are closely linked to melanin’s signal transduction capabilities and underpin its relevance in sensing applications. Recent advances in melanin-based sensing technologies encompass pH, humidity, chemical, biological, and optical platforms, with particular emphasis on hybrid systems incorporating graphene, silicon, or nanomaterials, and printable or wearable device architectures. These developments have enabled enhanced performance and broadened potential application fields. However, persistent challenges, including intrinsic heterogeneity, limited selectivity, relatively low electrical conductivity, and poor long-term operational stability, still limit practical implementation. Emerging molecular engineering and advanced fabrication strategies are being developed to address these limitations. Together, these findings position melanin as a versatile, eco-compatible, and functionally rich material, with a significant potential to underpin the next generation of sustainable sensing technologies. Full article

(This article belongs to the Special Issue Advanced Sensing Materials for Disease, Health and Environment Analysis)

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22 pages, 5645 KB

Open AccessArticle

Investigation of CO₂, NO₂, SO₂, and H₂O Gas Adsorption on Al₂O₃, TiO₂, and SiO₂ Surfaces

by Davron Sh. Kurbanov, Komiljon R. Yakubov, Vinoth Kumar Kazi, Selvarajan Premkumar, Mihhail Klopov, Rustam B. Bazarbayev and Smagul Zh. Karazhanov

Chemosensors 2026, 14(3), 65; https://doi.org/10.3390/chemosensors14030065 - 9 Mar 2026

Viewed by 1026

Abstract

This study presents a unified first-principles investigation of CO₂, NO₂, SO₂, and H₂O adsorption on Al₂O₃ (001), TiO₂ (001), and SiO₂ (001) surfaces, establishing the first cross-material, chemically consistent benchmark [...] Read more.

This study presents a unified first-principles investigation of CO₂, NO₂, SO₂, and H₂O adsorption on Al₂O₃ (001), TiO₂ (001), and SiO₂ (001) surfaces, establishing the first cross-material, chemically consistent benchmark for oxide–gas interactions. Calculated adsorption energies reveal strong chemisorption of SO₂ and NO₂ on Al₂O₃ and TiO₂, moderate H₂O binding—particularly on TiO₂ where hydroxylation is favored—and generally weak CO₂ interactions across all surfaces. Bader charge analysis provides atom-resolved insight into these trends, showing substantial electron transfer and pronounced oxygen-site polarization for strongly adsorbing gases, in contrast to the minimal charge redistribution characteristic of physisorbed CO₂. These charge-transfer signatures distinguish binding mechanisms, clarify the origins of material-specific selectivity, and link adsorption to expected variations in surface conductivity and sensor response. The combined energetic and electronic analysis also reveals competitive effects between humidity and CO₂ on surface hydroxylation and local electronic structure, a phenomenon critical for realistic sensing environments but previously unaddressed. Overall, this work delivers a rigorous comparative framework for understanding gas interactions with technologically relevant oxides and provides a solid foundation for future studies involving defects, dopants, surface reconstructions, and advanced functionalization strategies for environmental monitoring and energy-conversion devices. Full article

(This article belongs to the Special Issue Gas Sensors: Recent Advances and Future Challenges)

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18 pages, 2661 KB

Open AccessArticle

Impedance Sensor Based on ZnO/Graphite Composite with 3D-Printed Housing for Ionized Ammonia Detection in Continuous Water Flow

by Jorge A. Uc-Martín and Roberto G. Ramírez-Chavarría

Chemosensors 2026, 14(3), 64; https://doi.org/10.3390/chemosensors14030064 - 6 Mar 2026

Cited by 1 | Viewed by 1800

Abstract

High concentrations of ionized ammonia (

{NH}_{4}^{+}

) have been increasingly reported in municipal drinking water systems, posing a severe public health risk as excessive ingestion can lead to life-threatening conditions. Despite its importance, there is a significant lack of sensing [...] Read more.

High concentrations of ionized ammonia (

{NH}_{4}^{+}

) have been increasingly reported in municipal drinking water systems, posing a severe public health risk as excessive ingestion can lead to life-threatening conditions. Despite its importance, there is a significant lack of sensing technologies designed for continuous-flow monitoring outside laboratory settings, particularly those providing a robust, low-cost methodology suitable for resource-limited environments. To address these challenges, in this work, we report the development of an impedance sensor featuring a 3D-printed housing (3D-IS) for monitoring aqueous ionized ammonia (

{NH}_{4}^{+}

). The sensing electrodes, composed of zinc oxide and graphite, allow for the detection of concentrations 10 times lower and 60 times higher than current environmental limits. Its innovative, optimized design, analogous to that of industrial pressure gauges, highlights its potential for use in continuous water flow conditions outside the laboratory, such as water treatment plants. The level of

{NH}_{4}^{+}

in water is monitored by changes in impedance magnitude, with optimal performance observed at a frequency of 100 kHz. At this frequency, the impedance magnitude decreased by nearly two orders of magnitude as the

{NH}_{4}^{+}

concentration increased from 0 to 1 μM. Under these optimized conditions, the sensor exhibited a sensitivity of 2 kΩ/log(μM) and a linearity exceeding 90%. Furthermore, we propose an equivalent circuit model that accurately describes the experimental data, explaining the transduction process. We also describe, from an electrical perspective, the phenomenon of adsorption on the sensor’s transducer surface, thereby ensuring the device’s selectivity. The sensor was evaluated using dilutions of a standard ammonium solution for IC in distilled water, as well as with real groundwater samples, obtaining ∼99.7% of correlation with ion chromatography and a limit of detection of 2 μM. Finally, our device can provide information relatively quickly, with the added advantage of stable response under continuous-flow and real conditions, making it an attractive option for integration into a field sensor node. Full article

(This article belongs to the Special Issue Advances in Electrochemical Sensors: Emerging Materials, Techniques, and Applications)

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1 pages, 130 KB

Open AccessCorrection

Correction: Lipskikh et al. Development of a Sensitive and Cost-Effective MWCNTs/CCE Sensor for Electrochemical Determination of Prednisolone in Pharmaceuticals and Blood Serum. Chemosensors 2025, 13, 404

by Maksim V. Lipskikh, Elena I. Korotkova, Alina V. Erkovich, Margarita S. Mamina, Muhammad Saqib, Olga I. Lipskikh and Pradip K. Kar

Chemosensors 2026, 14(3), 63; https://doi.org/10.3390/chemosensors14030063 - 6 Mar 2026

Viewed by 454

Abstract

The blood serum that was used in the original publication [...] Full article

(This article belongs to the Special Issue Electrochemical Sensors and Biosensors: Recent Advances and Future Challenges)

12 pages, 809 KB

Open AccessArticle

Escherichia coli Optoelectronic Sensors for In Situ Monitoring of Selected Materials Across Water Supply Systems

by Yonatan Uziel, Natan Orlov, Loay Atamneh, Offer Schwartsglass, Shimshon Belkin and Aharon J. Agranat

Chemosensors 2026, 14(3), 62; https://doi.org/10.3390/chemosensors14030062 - 5 Mar 2026

Viewed by 816

Abstract

Chemical monitoring of pollutants and hazardous materials in water supply systems traditionally depends on centralized laboratories, advanced instrumentation, and trained personnel, limiting accessibility and preventing real-time, on-site analysis. This work presents an alternative cost-effective, field-deployable approach that uses genetically engineered bioluminescent bioreporters, encapsulated [...] Read more.

Chemical monitoring of pollutants and hazardous materials in water supply systems traditionally depends on centralized laboratories, advanced instrumentation, and trained personnel, limiting accessibility and preventing real-time, on-site analysis. This work presents an alternative cost-effective, field-deployable approach that uses genetically engineered bioluminescent bioreporters, encapsulated in self-sufficient alginate capsules and integrated with an optoelectronic detection circuit, to detect and quantify target materials in water. We have developed a scalable single-channel prototype featuring four sensing tracks—two for sample measurement, one for clean water, and one for a standard reference solution. The latter employs the standard ratio (SR) method to ensure robust quantification, compensating for batch variability and environmental effects. System characterization showed high uniformity across tracks. Validation with nalidixic acid (NA) demonstrated reliable quantitative performance, with a blind test estimation of 5.6 mg/L for a true concentration of 5 mg/L, well within the calibration error range. Additional sensitivity testing confirmed detection of mitomycin C (MMC) at concentrations as low as 50 µg/L. Overall, the results highlight the potential of bacterial chemical sensing as a practical and scalable tool for real-time, in situ water quality monitoring networks. Full article

(This article belongs to the Special Issue (Bio)Chemical Sensing in Real-World Applications—a Dedicated Issue for Young Researchers)

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15 pages, 1816 KB

Open AccessArticle

A Real-Time Automated Training and Sensing for Gas Odor (RATSGO) System for γ-Butyrolactone Detection

by Miha Kim, Yunkwang Oh, Sun-Seek Min, Keekwang Kim and Moonil Kim

Chemosensors 2026, 14(3), 61; https://doi.org/10.3390/chemosensors14030061 - 4 Mar 2026

Viewed by 777

Abstract

Herein, RATSGO (Real-time Automated Training and Sensing for Gas Odor), a fully automated live-animal olfactory training platform, for the detection of GBL as a sexual assault-facilitating drug is reported. The system integrates four distinct operant conditioning-based training paradigms, all executed without human intervention, [...] Read more.

Herein, RATSGO (Real-time Automated Training and Sensing for Gas Odor), a fully automated live-animal olfactory training platform, for the detection of GBL as a sexual assault-facilitating drug is reported. The system integrates four distinct operant conditioning-based training paradigms, all executed without human intervention, to enhance learning speed, consistency, and scalability. Using this fully automated framework, four rats were trained to identify γ-butyrolactone (GBL). Three of the four animals successfully reached the predefined learning completion criterion, whereas one failed to meet the criterion. Across 320 automated trials, the GBL rats achieved a mean detection accuracy of 90%, with sensitivity and specificity values of 97% and 82%, respectively. The corresponding positive and negative predictive values (PPV and NPV) were 85% and 96%. When challenged with GBL diluted in drinking water (180 trials), performance remained high, yielding 88% accuracy, 89% sensitivity, 87% specificity, 85% PPV, and 90% NPV. Similarly, in experiments involving GBL mixed with whisky (200 trials), the rats demonstrated robust recognition capability, achieving 90% overall accuracy, perfect sensitivity (100%), 84% specificity, 79% PPV, and 100% NPV. Importantly, odor discrimination performance was preserved when reassessed four months after the completion of training, indicating strong long-term retention of the learned odor representations. Collectively, these findings confirm that the RATSGO system supports rapid, stable, and precise odor learning, underscoring its promise as a practical and extensible biological sensing platform for chemical detection applications. Full article

(This article belongs to the Special Issue Low-Cost Chemosensors for Applications in Environment, Health, Food, and Industry Process Control, 2nd Edition)

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15 pages, 3960 KB

Open AccessCommunication

Hydrogen Sulfide Sensing Properties of Cu_XS-In Heterojunctions

by Nesrine Hafiene, Rayhane Zribi, Claudia Espro, Carlos Vázquez-Vázquez, Noureddine Bouguila and Giovanni Neri

Chemosensors 2026, 14(3), 60; https://doi.org/10.3390/chemosensors14030060 - 3 Mar 2026

Viewed by 690

Abstract

In this paper, a study on the development of indium-doped Cu_xS heterojunction-based conductometry sensors is presented. To fabricate the sensors, thick films of In-Cu_xS heterojunctions were sprayed directly on the alumina sensing platform provided with interdigitated Pt electrodes. The [...] Read more.

In this paper, a study on the development of indium-doped Cu_xS heterojunction-based conductometry sensors is presented. To fabricate the sensors, thick films of In-Cu_xS heterojunctions were sprayed directly on the alumina sensing platform provided with interdigitated Pt electrodes. The effect of the doping level with different nominal amounts of InCl₃ additive (0%, 3%, and 5%) on the structural, morphological and optical properties of Cu_xS films was first studied by XRD, AFM, UV-Vis and Raman spectroscopy. Moreover, the electrical and sensing characteristics towards low concentrations of hydrogen sulfide (H₂S) in air were investigated. The tests carried out clearly demonstrated the positive effect of In doping on the H₂S sensing performance of Cu_xS. The 5%-doped Cu_xS sensor showed the highest sensitivity to the target gas compared to the other sensor, as well as good stability and selectivity properties. Full article

(This article belongs to the Special Issue Recent Advances in Low-Cost Chemical Sensor Technologies for Environmental Monitoring Applications)

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17 pages, 3779 KB

Open AccessArticle

Amplitude-Modulated Virtual Sensing and FPGA-Enabled Accurate Recognition for Multiple Gases Using Electronic Nose

by Mingzhi Jiao, Junqiang Huang, Fukao Jia, Bin Bai and Yu Huo

Chemosensors 2026, 14(3), 59; https://doi.org/10.3390/chemosensors14030059 - 3 Mar 2026

Cited by 3 | Viewed by 1457

Abstract

This work presents an enhanced sensing framework for MEMS gas sensors based on tunable-amplitude periodic modulation, enabling multi-state excitation and feature enrichment without increasing the number of sensing elements. A multi-level periodic driving scheme is introduced to realize sensor virtualization, and the resulting [...] Read more.

This work presents an enhanced sensing framework for MEMS gas sensors based on tunable-amplitude periodic modulation, enabling multi-state excitation and feature enrichment without increasing the number of sensing elements. A multi-level periodic driving scheme is introduced to realize sensor virtualization, and the resulting multi-state responses are processed using a short-term baseline-tracking algorithm and a dislocated sparse-sampling strategy to improve feature discrimination. A lightweight multilayer perceptron (MLP) classifier is subsequently optimized and deployed on a field-programmable gate array (FPGA)-based accelerator to enable gas recognition under constrained hardware resources. Experimental results obtained from ternary mixtures of CH₄, CO, and H₂ demonstrate a classification accuracy of 98.5%, accompanied by a 60% reduction in model size and a fivefold improvement in computational speed on the FPGA accelerator. Full article

(This article belongs to the Special Issue Chemical Sensors for Volatile Organic Compound Detection, 2nd Edition)

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21 pages, 8567 KB

Open AccessArticle

High-Performance Cataluminescence Sensor Based on UIO-66/HKUST-1 Composite for Rapid Detection of Dichloromethane

by Taoyou Zhou, Jingjie Fan, Pengyu Zhang, Yun Wang, Xiangxiang Wang, Lining Bao, Mingjian Yi, Yuxian Guo, Bai Sun, Lingtao Kong and Shuguang Zhu

Chemosensors 2026, 14(3), 58; https://doi.org/10.3390/chemosensors14030058 - 3 Mar 2026

Viewed by 905

Abstract

Dichloromethane, as a widely used highly volatile industrial solvent, has neurotoxicity and hepatotoxicity and is suspected of being a carcinogen to humans. Therefore, it is necessary to develop a detection method that is more convenient for users, responds faster and is more efficient [...] Read more.

Dichloromethane, as a widely used highly volatile industrial solvent, has neurotoxicity and hepatotoxicity and is suspected of being a carcinogen to humans. Therefore, it is necessary to develop a detection method that is more convenient for users, responds faster and is more efficient than traditional analytical techniques. In cataluminescence (CTL) technology, as a promising alternative, the performance of CTL sensors critically depends on the design of high-performance sensitive materials. In this study, by rationally designing two typical metal–organic frameworks (MOFs), UIO-66 (zirconium-based) and HKUST-1 (copper-based), UIO-66/HKUST-1 nanocomposites for dichloromethane CTL detection were prepared by using a simple hydrothermal method. The experimental results show that when the composition ratio of UIO-66 is 2%, this composite exhibits the strongest CTL response to dichloromethane. Under optimized conditions, this sensor exhibits high selectivity, excellent stability (RSD = 3.98%), and a rapid response advantage for dichloromethane. The response time and recovery time are 5 and 19 s, respectively. It shows a good linear relationship within the concentration range of 8.4–84 ppm, along with a detection limit as low as 1.71 ppm. Analysis indicates that the enhanced performance stems from the formation of high-concentration oxygen vacancies and significantly strengthened synergistic effects at the UIO-66/HKUST-1 composite. This increases the concentration of surface reactive oxygen species, thereby providing more active sites for catalytic reactions. This work provides a robust and efficient sensing strategy for dichloromethane detection. Full article

(This article belongs to the Special Issue Advancements of Chemosensors and Biosensors in China—3rd Edition)

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47 pages, 8859 KB

Open AccessReview

Electrospun Nanofiber-Based SERS Substrates: Fabrication, Multiphasic Analysis, and Advanced Applications

by Yan Ke, Ge Cao, Ningning Zhou, Min Yang, Tianhong Huang, Jiali Xiong, Zhujun Li and Chuhong Zhu

Chemosensors 2026, 14(3), 57; https://doi.org/10.3390/chemosensors14030057 - 2 Mar 2026

Viewed by 2315

Abstract

Surface-enhanced Raman scattering (SERS) technology, with its high sensitivity and fingerprinting capability, has shown broad application prospects in environmental monitoring, food safety, biomedicine, and other fields. Electrospinning technology can produce flexible nanofiber membranes with high specific surface area and three-dimensional porous structures, providing [...] Read more.

Surface-enhanced Raman scattering (SERS) technology, with its high sensitivity and fingerprinting capability, has shown broad application prospects in environmental monitoring, food safety, biomedicine, and other fields. Electrospinning technology can produce flexible nanofiber membranes with high specific surface area and three-dimensional porous structures, providing an ideal platform for constructing high-performance SERS substrates for multiphasic analysis. This review systematically summarizes the fabrication strategies of fiber-based SERS substrates by using electrospinning technology, classified from three perspectives: material composition (polymer-based, ceramic-based, carbon fiber-based, and metal-based), spatial configuration (inner, surface, and inner-surface), and temporal sequence of plasmonic nanostructure (pre-synthesis, pre-reduction, post-reduction, post-modification, etc.). Furthermore, the sampling methods and measurement approaches of such substrates in liquid-phase, solid-phase, and gas-phase detection are discussed, with a focus on their applications in environmental pollution monitoring, food safety inspection, microbial identification, and biomedical diagnostics. Finally, the comparison of different preparation strategies and potential future directions are discussed, which could offer helpful guidance for the design and application of high-performance flexible SERS substrates. Full article

(This article belongs to the Section Materials for Chemical Sensing)

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16 pages, 4725 KB

Open AccessArticle

A Ratiometric Fluorescence Sensor Based on BSA Assembled Gold–Silver Bimetallic Nanoclusters for Highly Selective Detection of Chlortetracycline in Water

by Yu-Meng Dai, Weidong Ruan and Hong-Wei Li

Chemosensors 2026, 14(3), 56; https://doi.org/10.3390/chemosensors14030056 - 2 Mar 2026

Viewed by 708

Abstract

This study reports the precise synthesis of red-emitting gold–silver bimetallic nanoclusters (Au-AgNCs) via a one-pot hydrothermal method using thiolactic acid as both the ligand and reducing agent. The Au-AgNCs possess an average diameter of 1.85 nm and exhibit strong fluorescence emission at 687 [...] Read more.

This study reports the precise synthesis of red-emitting gold–silver bimetallic nanoclusters (Au-AgNCs) via a one-pot hydrothermal method using thiolactic acid as both the ligand and reducing agent. The Au-AgNCs possess an average diameter of 1.85 nm and exhibit strong fluorescence emission at 687 nm. Furthermore, they display notable assembly-induced emission enhancement (AIEE) properties. Upon assembly with bovine serum albumin (BSA), their fluorescence quantum yield significantly increases from 2.50% to 7.78%. Then Au-AgNCs@BSA assembly was employed as a ratiometric fluorescence sensor for the detection of chlortetracycline (CTC). In the presence of CTC, the original red emission of the assembly at 687 nm remained stable, while a new blue emission emerged at 420 nm and intensified progressively with CTC concentration. The ratio of the two emission intensities (I₄₂₀/I₆₈₇) exhibited an excellent linear correlation with CTC concentration over the range of 0.10 to 15 μM, with a limit of detection (LOD) of 20 nM. Notably, the sensor demonstrated exceptional selectivity for CTC, showing negligible response to common interfering substances such as metal ions, anions, amino acids, and crucially, other tetracycline antibiotics (tetracycline, oxytetracycline, and doxycycline). The practical applicability of the sensor was validated through the determination of spiked CTC in real water samples, achieving satisfactory recovery rates. In conclusion, this work accomplishes two key objectives: the development of novel AIEE-active Au-Ag bimetallic nanoclusters and the design of an efficient ratiometric sensing strategy. This approach enables the highly selective and sensitive detection of CTC, offering a promising tool for environmental monitoring. Full article

(This article belongs to the Special Issue Chemical Sensors for Bio-Medical and Environmental Applications, 2nd Edition)

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Graphical abstract

17 pages, 300 KB

Open AccessReview

Classical Effective Techniques to Evaluate Biological Compounds and Materials Toxicity Using Red Blood Cells as Biosensors

by César Iván Romo-Sáenz, Nancy Edith Rodríguez-Garza, Ana Laura Delgado-Miranda, Diana Laura Clark-Perez, Beatriz Elena Castro-Valenzuela, Celia María Quiñones-Flores, Alva Rocío Castillo-González, Andrés Garcia, Patricia Tamez-Guerra and Ricardo Gomez-Flores

Chemosensors 2026, 14(3), 55; https://doi.org/10.3390/chemosensors14030055 - 2 Mar 2026

Viewed by 1033

Abstract

Red blood cells represent a widely used cellular model in cytotoxicity studies, particularly in hemocompatibility assessments. As enucleated cells, which are abundant and easily accessible in both humans and animals, red blood cells allow for rapid, reproducible, and low-cost evaluation of the toxicity [...] Read more.

Red blood cells represent a widely used cellular model in cytotoxicity studies, particularly in hemocompatibility assessments. As enucleated cells, which are abundant and easily accessible in both humans and animals, red blood cells allow for rapid, reproducible, and low-cost evaluation of the toxicity of bioactive compounds, whether natural, synthetic, or nanoparticulate. From a functional perspective, the red blood cell membrane is highly sensitive to physical and chemical environmental changes (osmolarity, temperature, pH, and the presence of oxidizing agents). This sensitivity makes red blood cells an effective biosensor for detecting membrane damage, hemolysis, oxidative stress, methemoglobin formation, and aggregation processes. Therefore, in vitro tests using red blood cells allow for the preliminary evaluation in preclinical development, particularly for the early screening of cytotoxicity, membrane-disruptive effects, and hemocompatibility of small molecules, nanomaterials, and blood-contacting biomaterials. These techniques include hemocompatibility tests, evaluation of oxidative and osmotic damage, and evaluation of erythrocyte aggregation and function. However, the use of red blood cells as a cytotoxicity model also has significant limitations. As anucleate cells, erythrocytes lack organelles such as nuclei, mitochondria, or lysosomes, which prevents the evaluation of their effects on key intracellular processes such as protein synthesis, cell signaling, apoptosis, or endoplasmic reticulum stress. This lack of cellular complexity limits their usefulness as a sole model in studies of systemic toxicity or tissue-specific cytotoxicity. These tools offer an effective preliminary approach to anticipating risks in biomedical and pharmacological research. Full article

(This article belongs to the Section (Bio)chemical Sensing)

14 pages, 2905 KB

Open AccessArticle

Bimetallic MOF-Derived NiO/In₂O₃ Heterojunctions for NO₂ Sensing

by Yilin Chen, Xiaofei Weng, Guanglu Lei, Hao Jiang, Wei Zheng, Jun Zhang and Xianghong Liu

Chemosensors 2026, 14(3), 54; https://doi.org/10.3390/chemosensors14030054 - 2 Mar 2026

Viewed by 767

Abstract

Low-temperature (including room-temperature) gas sensors are crucial for energy-efficient and safe detection applications. In this study, we report the synthesis of In₂O₃-sensitized NiO nanoparticles (NPs) for NO₂ detection. The NiO/In₂O₃ hybrid materials were obtained by [...] Read more.

Low-temperature (including room-temperature) gas sensors are crucial for energy-efficient and safe detection applications. In this study, we report the synthesis of In₂O₃-sensitized NiO nanoparticles (NPs) for NO₂ detection. The NiO/In₂O₃ hybrid materials were obtained by pyrolysis of Ni/In bimetallic metal–organic framework (MOF) nanosheets (NSs) fabricated through ultrasonic synthesis and cation exchange. Gas sensing tests revealed that the In₂O₃ sensitization significantly enhances the NO₂ sensing performance of NiO, enabling a response of 1.5 at room temperature (RT) and an optimal response at 100 °C. The NiO/In₂O₃ sensor demonstrates enhanced selectivity toward NO₂, an ultra-low detection limit (41 ppb), and long-term stability. This study presents an effective MOF-derived route for developing high-performance low-power gas sensors. Full article

(This article belongs to the Section Materials for Chemical Sensing)

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10 pages, 1181 KB

Open AccessCommunication

Impedimetric Detection of Free Fatty Acids in Patient Serum Using Commercially Available Screen-Printed Carbon Electrode

by İsmail Oran, Halil İbrahim Özdemir, Turgay Yılmaz Kılıç, Hilmiye Deniz Ertuğrul Uygun, Hakan Gökalp Uzun, Barış Kılıçaslan, Evrim Şimşek, Yusuf Ali Altuncı, Şadiye Mıdık and Ali Murat Ergin

Chemosensors 2026, 14(3), 53; https://doi.org/10.3390/chemosensors14030053 - 24 Feb 2026

Viewed by 1103

Abstract

Objective: The performance of chrono-impedance measurement, a novel electrochemical method for determining free fatty acids (FA), was evaluated in a real-world clinical setting. Methods: Patients presenting to the emergency department with chest pain or discomfort were included. Routine diagnostic tests were performed in [...] Read more.

Objective: The performance of chrono-impedance measurement, a novel electrochemical method for determining free fatty acids (FA), was evaluated in a real-world clinical setting. Methods: Patients presenting to the emergency department with chest pain or discomfort were included. Routine diagnostic tests were performed in accredited laboratories. Chrono-impedance was measured using a screen-printed carbon electrode connected to a dedicated potentiostat. Serum total free-FA levels were determined by gas chromatography with flame ionization detection. Results: Among 104 patients, 21 received a specific diagnosis, while the remaining 83 patients were discharged with non-specific pain. Mean free-FA level was 0.9 ± 0.6 mM. Palmitic, linoleic, stearic, oleic, and arachidonic acids accounted for 74.9% of total free FAs. Impedance plots showed a characteristic logarithmic increase over time for all patients. When instantaneous impedance values at four different time points (10, 100, 376.6, and 500 s) were examined, a significantly strong correlation was observed between impedance and FA molarity (r = 0.8312, 0.9897, 0.9947, and 0.9951) and FA weight (r = 0.9572, 0.9878, 0.9996, and 0.9998), respectively. Conclusions: Chrono-impedance demonstrated a very high correlation with total free-FA levels in real patient samples. Full article

(This article belongs to the Section Electrochemical Devices and Sensors)

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