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13 pages, 1929 KB

Open AccessArticle

Scanning Electrochemical Microscopy of Nystatin-Treated Yeast Used for Biofuel Cells

by Katazyna Blazevic, Antanas Zinovicius, Juste Rozene, Tomas Mockaitis, Ingrida Bruzaite, Laisvidas Striska, Evaldas Balciunas, Arunas Ramanavicius, Almira Ramanaviciene and Inga Morkvenaite

Sensors 2026, 26(2), 605; https://doi.org/10.3390/s26020605 - 16 Jan 2026

Viewed by 553

Abstract

Biofuel cells (BFCs) generate electricity by converting chemical energy into electrical energy using biological systems. Saccharomyces cerevisiae (yeast) is an attractive biocatalyst for BFCs due to its robustness, low cost, and metabolic versatility; however, electron transfer from the intracellular reactions to the electrode [...] Read more.

Biofuel cells (BFCs) generate electricity by converting chemical energy into electrical energy using biological systems. Saccharomyces cerevisiae (yeast) is an attractive biocatalyst for BFCs due to its robustness, low cost, and metabolic versatility; however, electron transfer from the intracellular reactions to the electrode is limited by the cell membrane. Nystatin is an antifungal antibiotic that increases the permeability of fungal membranes. We hypothesized that sub-lethal nystatin treatment could enhance mediator-assisted electron transfer without compromising cell viability. In this work, yeast was treated with nystatin during cultivation at concentrations of up to 6 µg/mL and combined with a dual-mediator system consisting of a lipophilic mediator (9,10-phenanthrenequinone, PQ) and a hydrophilic mediator (potassium ferricyanide). Scanning electrochemical microscopy revealed that the dual-mediator system increased local current responses by approximately fivefold compared to a single mediator (from ~11 pA to ~59 pA), and that nystatin-treated yeast exhibited higher local electrochemical activity than untreated yeast (maximum currents of ~0.476 nA versus ~0.303 nA). Microbial fuel cell measurements showed that nystatin treatment increased the maximum power density from approximately 0.58 mW/m² to approximately 0.62 mW/m² under identical conditions. Nystatin concentrations between 4 and 5 µg/mL maintain yeast viability at near-control levels, while higher concentrations cause a decrease in viability. These results demonstrate that controlled, sub-lethal membrane permeabilization combined with a dual-mediator strategy can enhance electron transfer in yeast-based biofuel cells. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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20 pages, 3081 KB

Open AccessArticle

Fractional-Order Bioimpedance Modelling for Early Detection of Tissue Freezing in Cryogenic and Thermal Medical Applications

by Noelia Vaquero-Gallardo, Herminio Martínez-García and Oliver Millán-Blasco

Sensors 2026, 26(2), 603; https://doi.org/10.3390/s26020603 - 15 Jan 2026

Viewed by 694

Abstract

Cryotherapy and radiofrequency (RF) treatments modulate tissue temperature to induce therapeutic effects; however, improper application can result in thermal injury. Traditional temperature-based monitoring methods rely on multiple thermal sensors whose accuracy strongly depends on their number and spatial positioning, often failing to detect [...] Read more.

Cryotherapy and radiofrequency (RF) treatments modulate tissue temperature to induce therapeutic effects; however, improper application can result in thermal injury. Traditional temperature-based monitoring methods rely on multiple thermal sensors whose accuracy strongly depends on their number and spatial positioning, often failing to detect early tissue crystallization. This study introduces a fractional order bioimpedance modelling framework for the early detection of tissue freezing during cryogenic and thermal medical treatments, with the feasibility and effectiveness of this approach having been reported in our prior publications. While bioimpedance spectroscopy itself is a well-est. The corresponablished technique in biomedical engineering, its novel application to predict and identify premature freezing events provides a new pathway for safe and efficient energy-based therapies. Fractional-order models derived from the Cole family accurately reproduce the complex electrical behavior of biological tissues using fewer parameters than classical integer-order models, thus reducing both hardware requirements and computational cost. Experimental impedance data from human abdominal, gluteal, and femoral regions were modelled to extract fractional parameters that serve as sensitive indicators of phase-transition onset. The results demonstrate that the proposed approach enables real-time identification of freezing-induced electrical transitions, offering a physiologically grounded alternative to conventional temperature-based monitoring. Furthermore, the fractional order bioimpedance method exhibits high reproducibility and selectivity, and its analytical figures of merit, including the limits of detection and quantification, support its use for reliable real-time tissue monitoring and early injury detection. Overall, the proposed fractional order bioimpedance framework enhances both safety and control precision in cryogenic and thermal medical applications. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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19 pages, 43609 KB

Open AccessArticle

New Insights on Hydration Monitoring in Elderly Patients by Interdigitated Wearable Sensors

by Leila Es Sebar, Stefano Bonaldo, Loredana Cristaldi, Lara Franchin, Sabrina Grassini, Leonardo Iannucci, Luca Lombardo, Chiara Mineo, Andrea Neviani, Lorenzo Restelli, Isabella Sannino, Sarah Tonello and Cesare Svelto

Sensors 2025, 25(22), 7081; https://doi.org/10.3390/s25227081 - 20 Nov 2025

Cited by 2 | Viewed by 1618

Abstract

The progressive aging of the population requires reliable, non-invasive, and real-time tools to monitor hydration, prevent dehydration-related complications, and promote active aging in elderly patients. Wearable sensors based on interdigitated electrodes (IDEs) and on Electrochemical Impedance Spectroscopy (EIS) represent a promising tool thanks [...] Read more.

The progressive aging of the population requires reliable, non-invasive, and real-time tools to monitor hydration, prevent dehydration-related complications, and promote active aging in elderly patients. Wearable sensors based on interdigitated electrodes (IDEs) and on Electrochemical Impedance Spectroscopy (EIS) represent a promising tool thanks to their miniaturization, sensitivity to dielectric variations with humidity, and compatibility with flexible substrates. This study reports the design, fabrication, and metrological characterization of inkjet-printed IDEs for skin hydration monitoring, as a building block of a multisensor wearable device. IDEs were fabricated on polyimide substrates using silver nanoparticle-based ink. Their characterization involved the following: (i) morphological evaluation by scanning electron microscopy; (ii) EIS measurements in KCl solutions, leading to developing a regression model to correlate impedance with salt concentration; (iii) in vitro EIS validation on agar gel samples, which demonstrated a robust linear relationship between the impedance phase shift at 199.5

Hz

and water loss, with consistent sensitivity values across sensors. The results confirm the feasibility of IDEs for hydration monitoring, identifying optimal frequency ranges and validating regression models. These findings represent a critical step toward the development of multisensor wearable devices for elderly monitoring, enabling decentralized and continuous health monitoring to improve healthcare sustainability and telemedicine. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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11 pages, 1279 KB

Open AccessArticle

Indium Tin Oxide-Based Voltammetric Biosensor for the Detection of Antibodies Against the SARS-CoV-2 Virus Spike Protein

by Greta Zvirzdine, Maryia Drobysh, Almira Ramanaviciene, Vilma Ratautaite, Sarunas Zukauskas, Migle Stanciauskaite, Ieva Plikusiene and Arunas Ramanavicius

Sensors 2025, 25(21), 6737; https://doi.org/10.3390/s25216737 - 4 Nov 2025

Viewed by 2769

Abstract

This study aims to propose a plausible application of a novel electrochemical biosensing system for detecting antibodies against SARS-CoV-2 (anti-rS) in serum samples. The uniqueness of this study lies in the biosensor utilizing recombinant spike glycoprotein (SCoV2-rS) immobilized on an indium tin oxide [...] Read more.

This study aims to propose a plausible application of a novel electrochemical biosensing system for detecting antibodies against SARS-CoV-2 (anti-rS) in serum samples. The uniqueness of this study lies in the biosensor utilizing recombinant spike glycoprotein (SCoV2-rS) immobilized on an indium tin oxide (ITO) electrode modified with (3-aminopropyl)triethoxysilane (APTES). The electrochemical performance was evaluated using square wave voltammetry (SWV), demonstrating a linear relationship between the current density and anti-rS concentration. The limit of detection (LOD) was found to be 113 ng/mL (0.75 nM), and the limit of quantitation (LOQ) was equal to 338 ng/mL (2.25 nM). The reported electrochemical biosensor offers a straightforward and efficient method for evaluating the immune status of individuals who have recovered from COVID-19 and been vaccinated against this virus without the need for any redox probe. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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16 pages, 1422 KB

Open AccessArticle

Urea Detection in Phosphate Buffer and Artificial Urine: A Simplified Kinetic Model of a pH-Sensitive EISCAP Urea Biosensor

by Karen Simonyan, Astghik Tsokolakyan, Vahe Buniatyan, Artem Badasyan and Mkrtich Yeranosyan

Sensors 2025, 25(21), 6596; https://doi.org/10.3390/s25216596 - 26 Oct 2025

Cited by 1 | Viewed by 1415

Abstract

A simplified kinetic model for the quantitative analysis of a potentiometric, pH-based urea biosensor is presented. The device was an electrolyte–insulator–semiconductor capacitor (EISCAP) with a pH-sensitive Ta₂O₅ gate functionalized by a polyallylamine hydrochloride (PAH)/urease bilayer. Within the steady-state approximation, the [...] Read more.

A simplified kinetic model for the quantitative analysis of a potentiometric, pH-based urea biosensor is presented. The device was an electrolyte–insulator–semiconductor capacitor (EISCAP) with a pH-sensitive Ta₂O₅ gate functionalized by a polyallylamine hydrochloride (PAH)/urease bilayer. Within the steady-state approximation, the kinetic equations yielded an implicit algebraic relation linking the bulk urea concentration to the local pH at the sensor surface. Numerical solution of this equation, combined with a fitting routine, provides the apparent Michaelis–Menten constant (

K_{M}

) and the normalized maximum reaction rate (

{\bar{k}}_{V}

). Validation against the literature data confirmed the reliability of the approach. Experimental results were then analyzed in both phosphate buffer (PBS) and artificial urine (AU), covering urea concentrations of 0.1–50 mM. The fitted parameters showed comparable

K_{M}

values of 10.9 mM (PBS) and 32.4 mM (AU), but strongly different

{\bar{k}}_{V}

values:

2.2 \times 10^{- 4}

(PBS) versus

8.6 \times 10^{- 7}

(AU). The three-order reduction in AU was attributed to the inhibitory effects inherent to complex biological fluids. These findings highlight the importance of the model-based quantitative analysis of EISCAP biosensors, enabling the accurate characterization of immobilized enzyme layers and guiding optimization for applications in realistic sample matrices. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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13 pages, 281 KB

Open AccessArticle

Neurophysiology of Downhill Mountain Bike Athletes—Benchmark Assessments of Event-Related Potentials

by Matthew G. Neill, Elizabeth K. S. Fletcher, Ember Larson, Kristina Fraser, Scott Ramsay, Jonathan D. Smirl and Carolyn A. Emery

Sensors 2025, 25(17), 5388; https://doi.org/10.3390/s25175388 - 1 Sep 2025

Cited by 1 | Viewed by 1587

Abstract

Background: Downhill mountain biking (MTB) is a high-velocity sport where riders are potentially exposed to impacts and concussion. Rapidly obtained Event-Related Potentials (ERPs) are a promising use of portable electroencephalography for clinical assessment of concussion-related neurological impairment at the point of care. However, [...] Read more.

Background: Downhill mountain biking (MTB) is a high-velocity sport where riders are potentially exposed to impacts and concussion. Rapidly obtained Event-Related Potentials (ERPs) are a promising use of portable electroencephalography for clinical assessment of concussion-related neurological impairment at the point of care. However, the baseline neuroelectric profile of this specific sporting population is not fully understood. This study investigated the amplitude and latency of the N100, P300 and N400 ERPs at baseline among MTB athletes by age, sex and caffeine consumption. Methods: MTB athletes, aged 13–45, competing in the 2024 Whistler Crankworx MTB competition were recruited for this cross-sectional analysis. Self-reported sex, age and caffeine consumption were captured and pre-event baseline neurological evaluations of the N100, P300 and N400 ERPs (n = 92) were completed using a portable electroencephalograph (NeuroCatch). Results: Females had a 1.12 µV higher N100 amplitude (95%CI; 0.15, 2.08, p = 0.024) and 2.11 µV higher P300 amplitude (95%CI; 0.69, 3.52, p = 0.004) than males. Further, the N400 amplitude was 0.05 µV lower per year that age increases (95%CI; −0.08, −0.01, p = 0.011). Greater than normal caffeine consumption was associated with a 1.39 µV lower (95%CI; −2.68, −0.09, p = 0.036) and 18.96 ms (−28.29, −9.64, p < 0.001) faster N100 response. Conclusions: Age, sex and caffeine consumption must be considered to inform the clinical implement of ERPs for monitoring concussion in extreme sport athletes. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

22 pages, 2002 KB

Open AccessEditor’s ChoiceArticle

Uncovering the Kinematic Signature of Freezing of Gait in Parkinson’s Disease Through Wearable Inertial Sensors

by Francesco Castelli Gattinara Di Zubiena, Alessandro Zampogna, Martina Patera, Giovanni Cusolito, Ludovica Apa, Ilaria Mileti, Antonio Cannuli, Antonio Suppa, Marco Paoloni, Zaccaria Del Prete and Eduardo Palermo

Sensors 2025, 25(16), 5054; https://doi.org/10.3390/s25165054 - 14 Aug 2025

Cited by 2 | Viewed by 2041

Abstract

Parkinson’s disease (PD) is a disorder that causes a decrease in motor skills. Among the symptoms that have been observed, the most significant is the occurrence of Freezing of Gait (FoG), which manifests as an abrupt cessation of walking. This study investigates the [...] Read more.

Parkinson’s disease (PD) is a disorder that causes a decrease in motor skills. Among the symptoms that have been observed, the most significant is the occurrence of Freezing of Gait (FoG), which manifests as an abrupt cessation of walking. This study investigates the impact of spatiotemporal gait parameters using wearable inertial measurement units (IMUs). Notably, 30 PD patients (15 with FoG, 15 without) and 20 healthy controls were enrolled. Gait data were acquired using two foot-mounted IMUs and key parameters such as stride time, gait phase distribution, cadence, stride length, speed, and foot clearance were extracted. Results indicated a tangible decline in motor abilities in PD patients, especially in those with FoG. Differences were observed in the segmentation of gait phases, with diminished swing phase duration observed in patients, and in the diminished spatial parameters of stride length, velocity, and foot clearance. Additionally, to validate the results, the accuracy of IMU-derived clearance measurements was validated against an optoelectronic system. While the IMUs accurately detected maximum points, the minimum clearance showed a higher measurement error. These findings support the use of wearable IMUs as a reliable and low-cost alternative to laboratory systems for the assessment of gait abnormalities in PD. Moreover, they highlight the potential for early detection and monitoring of FoG in both clinical and home settings. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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14 pages, 9820 KB

Open AccessArticle

Zwitterionic Poly(sulfobetaine methacrylate) Brushes Functionalized Threads for DNA Extraction from Complex Cell Lysates

by Xianlong Shi, Liang Wu, Ke Ning, Xinmei Li, Lingke Feng, Yirong Chen and Ling Yu

Sensors 2025, 25(12), 3651; https://doi.org/10.3390/s25123651 - 11 Jun 2025

Viewed by 2710

Abstract

Thread-based analytical devices are low-cost, portable, and easy to use, making them ideal for detecting various biomolecules like glucose and DNA with minimal sample requirements, while also offering environmental benefits through their biodegradability. This study explores the potential of zwitterionic poly(sulfobetaine methacrylate) brushes [...] Read more.

Thread-based analytical devices are low-cost, portable, and easy to use, making them ideal for detecting various biomolecules like glucose and DNA with minimal sample requirements, while also offering environmental benefits through their biodegradability. This study explores the potential of zwitterionic poly(sulfobetaine methacrylate) brushes modified cotton thread (PSBMA@threads) as an innovative substitute for DNA solid-phase extraction. The PSBMA polymer brushes were synthesized on cotton threads via surface-initiated atom transfer radical polymerization (SI-ATRP). The usability of the PSBMA@threads for DNA extraction from cell lysates containing cell debris, proteins, and detergents was evaluated. Characterization using SEM, FTIR, and EDS confirmed the successful functionalization with PSBMA polymer brushes. The antifouling properties of PSBMA@threads, including resistance to non-specific protein adsorption and underwater oil repellency, were assessed. The results demonstrated selective DNA capture from protein and lipid-rich lysates. Optimized extraction parameters improved DNA yield, enabling efficient extraction from tumor cells, which successfully underwent PCR amplification. Comparative experiments with commercial silica membrane-based columns revealed that PSBMA@threads exhibited comparable DNA extraction capability. The PSBMA@threads maintained extraction capability after six months of ambient storage, highlighting its stability and cost-effectiveness for nucleic acid isolation in analytical applications. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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15 pages, 1941 KB

Open AccessArticle

Prediction of Influence of Environmental Factors on the Toxicity of Pentachlorophenol on E. coli-Based Bioassays

by Sulivan Jouanneau and Gerald Thouand

Sensors 2025, 25(10), 3215; https://doi.org/10.3390/s25103215 - 20 May 2025

Viewed by 1210

Abstract

Evaluating the impact of pollutants on ecosystems and human health is crucial. To achieve this, a wide range of bioassays, using organisms of different trophic levels, are available. Extrapolating the results of these bioassays to real environmental conditions remains a major challenge. This [...] Read more.

Evaluating the impact of pollutants on ecosystems and human health is crucial. To achieve this, a wide range of bioassays, using organisms of different trophic levels, are available. Extrapolating the results of these bioassays to real environmental conditions remains a major challenge. This study addresses this challenge by aiming to develop an algorithm capable of predicting the effect of environmental conditions on the impact of a toxicant, pentachlorophenol (PCP). Three abiotic factors were considered: pH, temperature, and conductivity. In the absence of the toxicant, the activity of Escherichia coli is influenced only by pH and temperature. However, exposed to PCP, the sensitivity of the bacteria was affected by these three factors. From these data, a predictive model was established to assess the intensity of the toxic effect induced by PCP. This model was validated using a validation dataset and demonstrated a strong correlation between the experimental and predicted values (r² ≈ 0.9). Thus, this approach enables the effective prediction of PCP’s effects by accounting for environmental variations. This proof of concept constitutes a potential alternative, complementary to conventional models like BLMs (focused on water chemistry for metals) and QSARs (linking structure to intrinsic toxicity), which often overlook the complexities of real-world environmental conditions. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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15 pages, 3016 KB

Open AccessArticle

Feasibility of Little Cherry/X-Disease Detection in Prunus avium Using Field Asymmetric Ion Mobility Spectrometry

by Gajanan S. Kothawade, Lav R. Khot, Abhilash K. Chandel, Cody Molnar, Scott J. Harper and Alice A. Wright

Sensors 2025, 25(7), 2034; https://doi.org/10.3390/s25072034 - 25 Mar 2025

Cited by 1 | Viewed by 1259

Abstract

Little cherry disease (LCD) and X-disease have critically impacted the Pacific Northwest sweet cherry (Prunus avium) industry. Current detection methods rely on laborious visual scouting or molecular analyses. This study evaluates the suitability of field asymmetric ion mobility spectrometry (FAIMS) for rapid [...] Read more.

Little cherry disease (LCD) and X-disease have critically impacted the Pacific Northwest sweet cherry (Prunus avium) industry. Current detection methods rely on laborious visual scouting or molecular analyses. This study evaluates the suitability of field asymmetric ion mobility spectrometry (FAIMS) for rapid detection of LCD and X-disease infection in three sweet cherry cultivars (‘Benton’, ‘Cristalina’, and ‘Tieton’) at the post-harvest stage. Stem cuttings with leaves were collected from commercial orchards and greenhouse trees. FAIMS operated at 1.5 L/min and 50 kPa, was used for headspace analysis. Molecular analyses confirmed symptomatic and asymptomatic samples. FAIMS data were processed for ion current sum (I_sum), maximum ion current (I_max), and area under the curve (I_AUC). Symptomatic samples showed higher ion currents in specific FAIMS regions (p < 0.05), with clear differences between symptomatic and asymptomatic samples across compensation voltage and dispersion field ranges. Cultivar-specific variation was also observed in the data. FAIMS spectra for LCD/X-disease symptomatic samples differed from those for asymptomatic samples in other Prunus species, such as peach and nectarines. These findings support FAIMS as a potential diagnostic tool for LCD/X disease. Further studies with controlled variables and key growth stages are recommended to realize early-stage detection. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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Review

Jump to: Research

47 pages, 5433 KB

Open AccessReview

Electrochemical Biosensors for Cancer Diagnosis and Prognosis Using Protein Biomarkers: Current Trends, Advances, and Clinical Translation Potential

by Michael E. J. López Mujica and Elena E. Ferapontova

Sensors 2026, 26(4), 1139; https://doi.org/10.3390/s26041139 - 10 Feb 2026

Cited by 3 | Viewed by 1565

Abstract

Cancer, a disease with high mortality, represents a major public health challenge. Increased access to early tumor screening, especially non-invasive liquid biopsy assays targeting blood-circulating protein biomarkers, has advanced cancer diagnosis and treatment, but these assays are still scarce. This work critically reviews [...] Read more.

Cancer, a disease with high mortality, represents a major public health challenge. Increased access to early tumor screening, especially non-invasive liquid biopsy assays targeting blood-circulating protein biomarkers, has advanced cancer diagnosis and treatment, but these assays are still scarce. This work critically reviews general strategies for the rapid and accurate electrochemical detection of serum proteins and surveys recent advances in liquid biopsy electrochemical biosensors targeting cancer-related proteins. Many of these approaches have achieved remarkable analytical sensitivity. The review further addresses key barriers to clinical translation and commercialization, including complex sample matrix effects that require rigorous standardization of preanalytical and analytical workflows, limited validation using patient samples, difficulties in accounting for interpatient variability, and practical considerations such as manufacturability, cost-effective scale-up, and long-term stability. Accordingly, particular emphasis is placed on clinically translatable detection methods, with a focus on the analytical and clinical validation of biosensors. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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23 pages, 4431 KB

Open AccessReview

Early Detection and Monitoring of Nephrolithiasis: The Potential of Electrochemical Sensors

by Kaiqiang Sun, Ningbin Zhao, Peizheng Shi, Zhuang Sun, Chen Ye, Li Fu, Dan Dai, Wubo Chu, Tao Cai, Hsu-Sheng Tsai and Cheng-Te Lin

Sensors 2025, 25(8), 2547; https://doi.org/10.3390/s25082547 - 17 Apr 2025

Cited by 2 | Viewed by 2634

Abstract

Nephrolithiasis (kidney stone disease) continues to pose a significant global health challenge, affecting millions of individuals and placing substantial economic pressures on healthcare systems. Traditional diagnostic methods—such as computed tomography (CT), ultrasound, and basic urinalysis—are often limited by issues including radiation exposure, lower [...] Read more.

Nephrolithiasis (kidney stone disease) continues to pose a significant global health challenge, affecting millions of individuals and placing substantial economic pressures on healthcare systems. Traditional diagnostic methods—such as computed tomography (CT), ultrasound, and basic urinalysis—are often limited by issues including radiation exposure, lower sensitivity in detecting small stones, operator dependency, and the inability to provide real-time analysis. In response, electrochemical sensors have emerged as innovative and powerful tools capable of the rapid, sensitive, and specific detection of key biomarkers associated with nephrolithiasis. This review highlights the advances in electrochemical approaches for monitoring oxalate and uric acid, the two primary metabolites implicated in kidney stone formation. We discuss the principles of electrode design and fabrication, including nanomaterial integration, 3D printing, and molecular imprinting, which have markedly improved detection limits and selectivity. Furthermore, we critically evaluate the practical challenges—such as sensor fouling, reproducibility, and stability in complex biological matrices—that currently impede widespread clinical implementation. The potentials for miniaturization and point-of-care integration are emphasized, with an eye toward continuous or home-based monitoring systems that can offer personalized insights into risk of stone formation and progression. By consolidating recent findings and exploring future trends in multi-analyte detection and wearable diagnostics, this review provides a roadmap for translating electrochemical sensors from research laboratories to routine clinical practice, ultimately aiming to enhance early intervention and improve patient outcomes in nephrolithiasis. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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16 pages, 2992 KB

Open AccessReview

Coelenterazine Analogs for Bioassays and Molecular Imaging

by Sung-Bae Kim, Genta Kamiya, Tadaomi Furuta and Shojiro A. Maki

Sensors 2025, 25(6), 1651; https://doi.org/10.3390/s25061651 - 7 Mar 2025

Viewed by 3232

Abstract

Coelenterazine (CTZ) is a common substrate of marine luciferases upon emission of bioluminescence (BL) in living organisms. Because CTZ works as a “luminophore” in the process of BL emission, the chemical modification has been centered for improving the optical properties of BL. In [...] Read more.

Coelenterazine (CTZ) is a common substrate of marine luciferases upon emission of bioluminescence (BL) in living organisms. Because CTZ works as a “luminophore” in the process of BL emission, the chemical modification has been centered for improving the optical properties of BL. In this review, we showcase recent advances in CTZ designs with unique functionalities. We first elucidate the light-emitting mechanisms of CTZ, and then focus on how the rational modification of CTZ analogs developed in recent years are connected to the development of unique functionalities even without luciferases, which include color tunability covering the visible region, specificity to various proteins (e.g., luciferase, albumin, and virus protein), and activatability to ions or reactive oxygen species (ROS) and anticancer drugs. This review provides new insights into the broad utilities of CTZ analogs with designed functionalities in bioassays and molecular imaging. Full article

(This article belongs to the Special Issue Feature Papers in Biosensors Section 2025)

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