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Search Results (2,082)

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11 pages, 529 KB  
Article
Impact of Sacubitril/Valsartan on Cardiac Autonomic Function Assessed Using Physiological Data from Implantable Cardioverter-Defibrillators
by Lucy Barone, Domenico Sergi, Giampiero Maglia, Luca Bontempi, Marzia Giaccardi, Matteo Baroni, Claudia Amellone, Antonio Curnis, Giuliano D’Alterio, Davide Saporito, Paolo Vinciguerra, Simone Cipani, Patrizio Mazzone, Massimo Giammaria, Gianfranco Mitacchione, Daniele Masarone, Francesca Fabbri, Andrea Vannelli, Irene Baldassarre, Martina Del Maestro, Daniele Giacopelli, Eduardo Celentano, Gabriele Zanotto and Francesco Barillàadd Show full author list remove Hide full author list
J. Clin. Med. 2026, 15(2), 719; https://doi.org/10.3390/jcm15020719 - 15 Jan 2026
Abstract
Background/Objectives: Sacubitril/Valsartan is a cornerstone therapy to improve outcomes in patients with heart failure with reduced ejection fraction (HFrEF). This study aimed to investigate the effect of Sacubitril/Valsartan on cardiac autonomic balance using physiological sensor data obtained from implantable cardioverter-defibrillators (ICDs) or [...] Read more.
Background/Objectives: Sacubitril/Valsartan is a cornerstone therapy to improve outcomes in patients with heart failure with reduced ejection fraction (HFrEF). This study aimed to investigate the effect of Sacubitril/Valsartan on cardiac autonomic balance using physiological sensor data obtained from implantable cardioverter-defibrillators (ICDs) or cardiac resynchronization therapy defibrillators (CRT-Ds). Methods: This observational study involved 54 ICD and CRT-D patients who initiated Sacubitril/Valsartan therapy to treat HFrEF. The evaluated key parameters included heart rate variability (HRV), 24 h mean heart rate (24 h-HR), and nocturnal heart rate (nHR). Device electrical parameters and ventricular arrhythmias were also assessed. The data were collected by remote monitoring and averaged over a 7-day window at baseline (before treatment) and at 3 and 12 months after treatment initiation. Results: Sacubitril/Valsartan significantly improved HRV at 3 months (from 78.6 ms [interquartile range: 54.2–104.6] to 80.8 ms [60.8–108.0]; p = 0.041), reduced 24 h-HR (from 73.2 bpm [67.3–77.7] to 69.9 bpm [64.2–75.7]; p = 0.016), and reduced nHR (from 63.0 bpm [58.1–70.0] to 60.4 bpm [56.0–68.6]; p = 0.028). No significant changes in HRV, 24 h-HR, and nHR were observed between 3- and 12-month follow-up. The device electrical parameters were not influenced by the treatment. While the overall ventricular arrhythmia burden did not change post-treatment, patients with pre-treatment arrhythmias experienced a significant reduction in episodes from 2.97 (pre-treatment) to 0.82 (post-treatment) events per 100 patient years (p = 0.008). Conclusions: Sacubitril/Valsartan therapy in HFrEF patients was associated with statistically significant changes in cardiac autonomic indices, including a small increase in HRV and a slight reduction in heart rate, mainly during the first three months of treatment. Full article
(This article belongs to the Section Cardiovascular Medicine)
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12 pages, 2700 KB  
Proceeding Paper
A Low-Cost and Reliable IoT-Based NFT Hydroponics System Using ESP32 and MING Stack
by Tolga Demir and İhsan Çiçek
Eng. Proc. 2026, 122(1), 3; https://doi.org/10.3390/engproc2026122003 - 14 Jan 2026
Viewed by 33
Abstract
This paper presents the design and implementation of an IoT-based automation system for indoor hydroponic plant cultivation using the Nutrient Film Technique. The system employs an ESP32-based controller with multiple sensors and actuators. These enable real-time monitoring and control of pH, TDS, temperature, [...] Read more.
This paper presents the design and implementation of an IoT-based automation system for indoor hydroponic plant cultivation using the Nutrient Film Technique. The system employs an ESP32-based controller with multiple sensors and actuators. These enable real-time monitoring and control of pH, TDS, temperature, humidity, light, tank level, and flow conditions. A modular five-layer architecture was developed. It combines the MING stack, which includes MQTT communication, InfluxDB time-series storage, Node-RED flow processing, and Grafana visualization. The system also includes a Flutter-based mobile app for remote access. Key features include temperature-compensated calibration, hysteresis-based control algorithms, dual-mode operation, TLS/ACL security, and automated alarm mechanisms. These features enhance reliability and safety. Experimental results showed stable pH/TDS regulation, dependable actuator and alarm responses, and secure long-term data logging. The proposed open-source and low-cost platform is scalable. It provides a solution for small-scale producers and urban farming, bridging the gap between academic prototypes and production-grade smart agriculture systems. In comparison to related works that mainly focus on monitoring, this study advances the state of the art. It combines continuous time-series logging, secure communication, flow verification, and integrated safety mechanisms to provide a reproducible testbed for future smart agriculture research. Full article
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12 pages, 3112 KB  
Article
CdSe/ZnS QDs and O170 Dye-Decorated Spider Silk for pH Sensing
by Yangjie Tang, Hao Zhang, Ran Xiao, Qixuan Wu, Jie Zhang, Chenchen Liu, Peng Yu, Guowei Yang and Hongxiang Lei
Coatings 2026, 16(1), 110; https://doi.org/10.3390/coatings16010110 - 14 Jan 2026
Viewed by 55
Abstract
Effective in situ pH sensing holds exciting prospects in environmental and biomedical applications, but still faces a great challenge. Until now, pH sensors with small size, high sensitivity, good stability and repeatability, great biosafety, wide detection range, and flexible structure have rarely been [...] Read more.
Effective in situ pH sensing holds exciting prospects in environmental and biomedical applications, but still faces a great challenge. Until now, pH sensors with small size, high sensitivity, good stability and repeatability, great biosafety, wide detection range, and flexible structure have rarely been reported. Herein, we propose a novel dual-emission ratiometric fluorescent pH sensor by decorating ethyl cellulose (EC)-encapsulated CdSe/ZnS quantum dots (QDs) and oxazine 170 perchlorate (O170 dye) on the surface of the spider silk. When a 473 nm excitation light is coupled into the pH sensor, the evanescent wave transmitting along the surface of the spider silk will excite the CdSe/ZnS QDs and then the O170 dye based on the fluorescence resonance energy transfer (FRET) effect from the QDs; thus, the pH sensing of the surrounding liquid environment can be achieved in real time by collecting the photoluminescence (PL) spectra of the pH sensor and measuring the emission intensity ratio of the two fluorescent materials. The sensor has also demonstrated a high sensing sensitivity (0.775/pH unit) within a wide pH range of 1.92–12.11, as well as excellent reusability and reversibility, structure and time stability, biocompatibility, and biosafety. The proposed pH sensor has a potential application in an in situ monitor of water microenvironments, cellular metabolism, tumor microenvironments, etc. Full article
(This article belongs to the Special Issue Advances in Nanostructured Thin Films and Coatings, 3rd Edition)
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11 pages, 245 KB  
Article
Emotional Well-Being and Glycemic Control in People with Diabetes After a Multidisciplinary Hybrid Education
by Carmen Amelia Ruiz-Trillo, Ana Pérez-Morales, Ana Cortés-Lerena, Pilar Santa Cruz-Álvarez, Mónica Enríquez-Macias, Manuel Pabón-Carrasco, Miguel Garrido-Bueno, Rocío Romero-Castillo and Virginia Bellido
Healthcare 2026, 14(2), 198; https://doi.org/10.3390/healthcare14020198 - 13 Jan 2026
Viewed by 119
Abstract
Background/Objectives: Multidisciplinary hybrid educational programs combined with continuous glucose monitoring may contribute to improved self-management in adults with type 1 diabetes mellitus (T1DM); however, real-world evidence remains limited. This study assessed the effects of an educational intervention integrated with continuous glucose monitoring on [...] Read more.
Background/Objectives: Multidisciplinary hybrid educational programs combined with continuous glucose monitoring may contribute to improved self-management in adults with type 1 diabetes mellitus (T1DM); however, real-world evidence remains limited. This study assessed the effects of an educational intervention integrated with continuous glucose monitoring on glycemic control and patient-reported outcomes in adults with T1DM. Methods: We conducted a single-group quasi-experimental study including 210 adults with T1DM from a public hospital. The nurse-led hybrid intervention consisted of a 2-h in-person group educational session followed by an individual telematic follow-up session. All participants used continuous glucose monitoring. The primary outcome was the change in HbA1c at 9 months. Secondary outcomes included continuous glucose monitoring metrics, diabetes-related quality of life, treatment satisfaction, and hypoglycemia awareness. Results: HbA1c showed a statistically significant but modest reduction from 7.70 ± 1.10% to 7.45 ± 0.91% following the intervention (p = 0.003). No statistically significant changes were observed in continuous glucose monitoring metrics, including time in range, time below and above range, mean glucose, glycemic variability, or sensor wear time. In terms of emotional well-being, treatment satisfaction increased significantly (8.17 ± 7.86 vs. 12.73 ± 5.49; p < 0.001), and the Clarke score showed a statistically significant but modest decrease (2.49 ± 1.90 vs. 2.12 ± 1.88; p = 0.017). Although the overall quality of life score did not change significantly, statistically significant differences were observed in several subscales, including satisfaction, impact, and diabetes-related concern. Conclusions: A multidisciplinary hybrid educational intervention integrated with continuous glucose monitoring was associated with modest improvements in HbA1c and statistically significant, though limited, enhancements in quality of life, treatment satisfaction, and hypoglycemia awareness in adults with T1DM. These findings suggest that similar educational models may have a supportive role in routine care. Full article
(This article belongs to the Special Issue Multidisciplinary Approaches to Chronic Disease Management)
18 pages, 1763 KB  
Article
Nucleophilic Addition of Stabilized Phosphorus Ylides to Closo-Decaborate Nitrilium Salts: A Synthetic Route to Boron Cluster-Functionalized Iminoacyl Phosphoranes and Their Application in Potentiometric Sensing
by Vera V. Voinova, Eugeniy S. Turyshev, Sergey S. Novikov, Nikita A. Selivanov, Alexander Yu. Bykov, Ilya N. Klyukin, Andrey P. Zhdanov, Mikhail S. Grigoriev, Konstantin Yu. Zhizhin and Nikolay T. Kuznetsov
Molecules 2026, 31(2), 231; https://doi.org/10.3390/molecules31020231 - 9 Jan 2026
Viewed by 205
Abstract
This work explores a novel and efficient synthetic approach to a new class of boron cluster derivatives via the nucleophilic addition of stabilized phosphorus ylides, Ph3P=CHR2 (R2 = COOEt, CN), to a series of nitrilium salts of the closo [...] Read more.
This work explores a novel and efficient synthetic approach to a new class of boron cluster derivatives via the nucleophilic addition of stabilized phosphorus ylides, Ph3P=CHR2 (R2 = COOEt, CN), to a series of nitrilium salts of the closo-decaborate anion, [2-B10H9NCR1] (R1 = Me, Et, nPr, iPr, Ph). The reaction proceeds regio- and stereospecifically, affording a diverse range of iminoacyl phosphorane derivatives, [2-B10H9NH=C(R1)C(PPh3)R2], in high isolated yields (up to 95%). The obtained compounds (10 examples) were isolated as tetrabutylammonium or tetraphenylphosphonium salts and thoroughly characterized by multinuclear NMR (11B, 1H, 13C, 31P), high-resolution mass spectrometry, and single-crystal X-ray diffraction. The reaction feasibility was found to be strongly influenced by the steric hindrance of the R1 group. Furthermore, the practical utility of these novel hybrids was demonstrated by employing the [2-B10H9NH=C(CH3)C(COOC2H5)=PPh3] anion as a highly effective membrane-active component in ion-selective electrodes. The developed tetraphenylphosphonium (TPP+) sensor exhibited a near-Nernstian response, a low detection limit of 3 × 10−8 M, and excellent selectivity over a range of common inorganic and organic cations, showcasing the potential of closo-borate-based ionophores in analytical chemistry. Full article
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23 pages, 4558 KB  
Article
Copper Ion Detection Using Green Precursor-Derived Carbon Dots in Aqueous Media
by Chao-Sheng Chen, Miao-Wei Lin and Chin-Feng Wan
Chemosensors 2026, 14(1), 21; https://doi.org/10.3390/chemosensors14010021 - 9 Jan 2026
Viewed by 153
Abstract
Highly accurate quantitative detection of heavy metals is crucial for preventing environmental pollution and safeguarding public health. To address the demand for sensitive and specific detection of Cu2+ ions, we have developed carbon dots using a simple hydrothermal process. The synthesized carbon [...] Read more.
Highly accurate quantitative detection of heavy metals is crucial for preventing environmental pollution and safeguarding public health. To address the demand for sensitive and specific detection of Cu2+ ions, we have developed carbon dots using a simple hydrothermal process. The synthesized carbon dots are highly stable in aqueous media, environmentally friendly, and exhibit strong blue photoluminescence at 440 nm when excited at 352 nm, with a quantum yield of 5.73%. Additionally, the size distribution of the carbon dots ranges from 2.0 to 20 nm, and they feature excitation-dependent emission. They retain consistent optical properties across a wide pH range and under high ionic strength. The photoluminescent probes are selectively quenched by Cu2+ ions, with no interference observed from other metal cations such as Ag+, Ca2+, Cr3+, Fe2+, Fe3+, Hg2+, K+, Mg2+, Sn2+, Pb2+, Sr2+, and Zn2+. The emission of carbon dots exhibits a strong linear correlation with Cu2+ concentration in the range of 0–14 μM via a static quenching mechanism, with a detection limit (LOD) of 4.77 μM in water. The proposed carbon dot sensor is low cost and has been successfully tested for detecting Cu2+ ions in general water samples collected from rivers in Taiwan. Full article
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26 pages, 3467 KB  
Article
Antimicrobial Effect of Oregano Essential Oil in Na-Alginate Edible Films for Shelf-Life Extension and Safety of Feta Cheese
by Angeliki Doukaki, Aikaterini Frantzi, Stamatina Xenou, Fotoula Schoina, Georgia Katsimperi, George-John Nychas and Nikos Chorianopoulos
Pathogens 2026, 15(1), 65; https://doi.org/10.3390/pathogens15010065 - 8 Jan 2026
Viewed by 245
Abstract
The use of natural antimicrobials and advanced sensor technologies is increasingly explored to improve the safety and quality of dairy products like cheese. The current work evaluated the effect of sodium alginate edible films enriched with oregano essential oil (EO) on the microbial [...] Read more.
The use of natural antimicrobials and advanced sensor technologies is increasingly explored to improve the safety and quality of dairy products like cheese. The current work evaluated the effect of sodium alginate edible films enriched with oregano essential oil (EO) on the microbial spoilage of Feta cheese and the fate of Escherichia coli O157:H7 and Listeria monocytogenes during storage. Samples were inoculated with approximately a 4 log CFU/g of pathogens and subsequently wrapped with edible films containing EO or left without, serving as controls. Samples were stored under aerobic and vacuum conditions at 4 and 12 °C. Microbiological analyses, pH, and sensory attributes were monitored during storage, while multispectral imaging (MSI) devices were used for rapid, non-invasive quality assessment. EO films moderately suppressed spoilage and pathogen survival, particularly under aerobic conditions. The MSI spectral data coupled with machine learning models provided reasonable results for the estimation of yeast and mould populations, with the best models coming from aerobic conditions, from benchtop-MSI data, with R2 = 0.726 and RMSE = 0.426 from the Neural Networks model, and R2 = 0.661 and RMSE = 0.696 from the LARS model. The results highlight the combined potential of natural antimicrobial films and MSI-based sensors for extending Feta cheese shelf life and enabling rapid, non-destructive monitoring, respectively. Full article
(This article belongs to the Special Issue Diagnosis, Immunopathogenesis and Control of Bacterial Infections)
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19 pages, 1753 KB  
Article
Multimodal Physiological Monitoring Using Novel Wearable Sensors: A Pilot Study on Nocturnal Glucose Dynamics and Meal-Related Cardiovascular Responses
by Emi Yuda, Yutaka Yoshida, Hiroyuki Edamatsu and Junichiro Hayano
Bioengineering 2026, 13(1), 69; https://doi.org/10.3390/bioengineering13010069 - 8 Jan 2026
Viewed by 282
Abstract
This pilot study investigated multimodal physiological monitoring using minimally invasive and wearable sensors across two experimental settings. Experiment 1 involved five healthy adults (1 female) who simultaneously wore an interstitial fluid glucose (ISFG) sensor and a ring-type wearable device during sleep (00:00–06:00). Time-series [...] Read more.
This pilot study investigated multimodal physiological monitoring using minimally invasive and wearable sensors across two experimental settings. Experiment 1 involved five healthy adults (1 female) who simultaneously wore an interstitial fluid glucose (ISFG) sensor and a ring-type wearable device during sleep (00:00–06:00). Time-series analyses revealed that ISFG levels decreased during sleep in four of the five participants. ISFG values were significantly lower in the latter half of the sleep period compared with the first half (0–3 h vs. 3–6 h, p = 0.01, d = 2.056). Four participants also exhibited a mild reduction in SpO2 between 03:00–04:00. These results suggest that nocturnal ISFG decline may be associated with subtle oxygen-saturation dynamics. Experiment 2 examined whether wearable sensors can detect physiological changes across meal-related phases. Nine male participants were monitored for heart rate (HR) and skin temperature during three periods: pre-meal (Phase 1: 09:00–09:30), during meal consumption (Phase 2: 12:30–13:00), and post-meal (Phase 3: 13:00–13:30). A paired comparison demonstrated a significant difference in median HR between Phase 1 and Phase 2 (p = 0.029, d = 0.812), indicating a large effect size. In contrast, HR–temperature correlation was weak and not statistically significant (Pearson r = 0.067, p = 0.298). Together, these findings demonstrate that multimodal wearable sensing can capture both nocturnal glucose fluctuations and meal-induced cardiovascular changes. This integrative approach may support real-time physiological risk assessment and future development of remote healthcare applications. Full article
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15 pages, 925 KB  
Article
The Softball Pitching Plane (SPP): A Reliable Geometric Descriptor of Arm Trajectory and Its Relationship to Ball Velocity in Adolescent Pitchers
by Kai-Jen Cheng, Ian P. Jump, Ryan M. Zappa, Anthony W. Fava, Madeline R. Klubertanz, Joseph H. Caplan and Gretchen D. Oliver
Appl. Sci. 2026, 16(2), 574; https://doi.org/10.3390/app16020574 - 6 Jan 2026
Viewed by 373
Abstract
This study introduced Softball Pitching Plane (SPP), a best-fit geometric plane designed to characterize the throwing arm spatial trajectory during the windmill softball pitch. The purpose was to evaluate the reliability of this planar representation and determine whether deviations from the SPP were [...] Read more.
This study introduced Softball Pitching Plane (SPP), a best-fit geometric plane designed to characterize the throwing arm spatial trajectory during the windmill softball pitch. The purpose was to evaluate the reliability of this planar representation and determine whether deviations from the SPP were associated with ball velocity. Forty-nine adolescent softball pitchers each performed 15 drop-ball pitches (735 total pitches). Kinematics were recorded using a 15-sensor electromagnetic tracking system. A weighted orthogonal least-squares algorithm was applied to compute the best-fit plane across three intervals (WU–BR, TOP–BR, and DS–BR). Reliability was assessed using within-subject variability, leave-one-trial-out error, and ICCs. Linear mixed-effects models were used to examine associations between SPP parameters and ball velocity. The downswing–ball release interval of the wrist trajectory showed the most stable planar pattern (RMS = 0.053 m). SPP parameters demonstrated high reliability (CV ≤ 4.2%; ICC = 0.81–0.90). RMS deviation negatively predicted ball velocity at both within-pitcher (−0.11 km·h−1 per cm, p = 0.003) and between-pitcher levels (−0.40 km·h−1 per cm, p = 0.03). These findings indicate that, in adolescent softball pitchers, the SPP provides a reliable geometric description of throwing-arm motion during the downswing–ball release phase, with reduced deviation associated with higher pitch velocity. Full article
(This article belongs to the Special Issue Biomechanics and Sport Engineering: Latest Advances and Prospects)
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18 pages, 566 KB  
Review
Spider Silk in Fiber-Optic Sensors: Properties, Applications and Challenges
by Shuo Liu and Dongyan Zhang
Textiles 2026, 6(1), 5; https://doi.org/10.3390/textiles6010005 - 5 Jan 2026
Viewed by 216
Abstract
Spider silk, as a natural polymer fiber, possesses high tensile strength, good toughness, as well as unique thermal, optical, and biocompatibility properties. It has attracted much attention in various fields. The field of optical fiber sensors has a promising future. Given the excellent [...] Read more.
Spider silk, as a natural polymer fiber, possesses high tensile strength, good toughness, as well as unique thermal, optical, and biocompatibility properties. It has attracted much attention in various fields. The field of optical fiber sensors has a promising future. Given the excellent performance of spider silk, introducing spider silk into the field of optical fiber sensors can broaden its application scope. This paper comprehensively reviews the outstanding characteristics of spider silk and spider silk sensors based on these characteristics, such as pH sensors, breath humidity sensors, cell temperature sensors, and blood glucose sensors applied in living organisms, as well as magnetic field sensors and refractive index sensors applied in industrial fields. It also analyzes in detail the problems faced during the collection and synthesis of spider silk, aiming to provide a reference for research on the application of spider silk in the field of optical fiber sensors. Full article
(This article belongs to the Collection Feature Reviews for Advanced Textiles)
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16 pages, 9156 KB  
Article
Spiropyran-Modified Cellulose for Dual Solvent and Acid/Base Vapor Sensing
by Daniel D. S. de Sá, João P. C. Trigueiro, Luiz F. C. de Oliveira, Hernane S. Barud, Frank Alexis, Roberto S. Nobuyasu, Flávio B. Miguez and Frederico B. De Sousa
Chemosensors 2026, 14(1), 17; https://doi.org/10.3390/chemosensors14010017 - 4 Jan 2026
Viewed by 326
Abstract
Stimuli-responsive materials based on renewable biopolymers are highly attractive for developing sustainable chemical sensors. Here, two spiropyran derivatives (SP1 and SP2) were synthesized and covalently grafted onto cellulose, yielding the functional materials Cel-SP1 and Cel-SP2. Cellulose was selected [...] Read more.
Stimuli-responsive materials based on renewable biopolymers are highly attractive for developing sustainable chemical sensors. Here, two spiropyran derivatives (SP1 and SP2) were synthesized and covalently grafted onto cellulose, yielding the functional materials Cel-SP1 and Cel-SP2. Cellulose was selected as a biocompatible, biodegradable, and renewable support able to provide a stable, hydrogen-bond-rich microenvironment for chromic responses. Raman spectroscopy confirmed successful esterification, while SEM-EDS analyses revealed preserved cellulose morphology and the incorporation of nitrogen-rich spiropyran moieties. Both materials exhibited pronounced solvatochromic and pH-dependent behaviors in the solid state. Diffuse reflectance measurements revealed distinct bathochromic or hypsochromic shifts depending on solvent polarity and specific solute–matrix interactions, with DMF and DMSO producing the strongest responses. Under acidic vapors, both materials generated new absorption bands consistent with the formation of protonated merocyanine species, whereas basic vapors promoted partial or full reversion to the spiropyran form. Cel-SP1 and Cel-SP2 also displayed solvent- and pH-dependent luminescence, with Cel-SP2 showing a markedly higher sensitivity to protonation. Prototype solvent strips and acid/base vapor indicators demonstrated fast, naked-eye, reversible chromic transitions. These results highlight spiropyran-modified cellulose as an effective, renewable platform for dual solvent and acid/base vapor sensing. Full article
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23 pages, 3269 KB  
Article
Benzoxazole Iminocoumarins as Multifunctional Heterocycles with Optical pH-Sensing and Biological Properties: Experimental, Spectroscopic and Computational Analysis
by Marina Galić, Ana Čikoš, Leentje Persoons, Dirk Daelemans, Karolina Vrandečić, Maja Karnaš, Marijana Hranjec and Robert Vianello
Chemosensors 2026, 14(1), 15; https://doi.org/10.3390/chemosensors14010015 - 3 Jan 2026
Viewed by 230
Abstract
A novel series of benzoxazole-derived iminocoumarins was synthesized via a Knoevenagel condensation and fully characterized using NMR, UV–Vis spectroscopy, and computational methods. Their photophysical properties were systematically examined in solvents of varying polarity, revealing pronounced effects of both substituents and solvent environment on [...] Read more.
A novel series of benzoxazole-derived iminocoumarins was synthesized via a Knoevenagel condensation and fully characterized using NMR, UV–Vis spectroscopy, and computational methods. Their photophysical properties were systematically examined in solvents of varying polarity, revealing pronounced effects of both substituents and solvent environment on absorption maxima and intensity. Derivatives bearing electron-donating substituents on the coumarin core exhibited distinct and reversible pH-responsive spectral shifts, confirming their potential as optical pH probes. Experimental pKa values derived from absorption titrations showed excellent agreement with DFT-calculated data, validating the proposed protonation-deprotonation equilibria and associated electronic structure changes. Structure–property relationships revealed that electron-donating groups enhance intramolecular charge transfer, while electron-withdrawing substituents modulate spectral response and stability. In parallel, the compounds were evaluated for antiproliferative, antiviral, and antifungal activities in vitro. Strong electron-donating substituents were associated with potent but non-selective cytotoxicity, whereas derivatives bearing electron-withdrawing groups displayed moderate and more selective antiproliferative effects against leukemia cell lines. Antifungal screening revealed moderate inhibition of phytopathogenic fungi, particularly for compounds with electron-withdrawing or methoxy substituents. Overall, these findings demonstrate that benzoxazole iminocoumarins represent a promising class of multifunctional heterocycles with potential applications as optical pH sensors and scaffolds for bioactive compound development. Full article
(This article belongs to the Section Optical Chemical Sensors)
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16 pages, 1219 KB  
Article
Flexible Inkjet-Printed pH Sensors for Application in Organ-on-a-Chip Biomedical Testing
by Željka Boček, Donna Danijela Dragun, Laeticia Offner, Sara Krivačić, Ernest Meštrović and Petar Kassal
Biosensors 2026, 16(1), 38; https://doi.org/10.3390/bios16010038 - 3 Jan 2026
Viewed by 346
Abstract
Reliable models of the lung environment are important for research on inhalation products, drug delivery, and how aerosols interact with tissue. pH fluctuations frequently accompany real physiological processes in pulmonary environments, so monitoring pH changes in lung-on-a-chip devices is of considerable relevance. Presented [...] Read more.
Reliable models of the lung environment are important for research on inhalation products, drug delivery, and how aerosols interact with tissue. pH fluctuations frequently accompany real physiological processes in pulmonary environments, so monitoring pH changes in lung-on-a-chip devices is of considerable relevance. Presented here are flexible, miniaturized, inkjet-printed pH sensors that have been developed with the aim of integration into lung-on-a-chip systems. Different types of functional pH-sensitive materials were tested: hydrogen-selective plasticized PVC membranes and polyaniline (both electrodeposited and dropcast). Their deposition and performance were evaluated on different flexible conducting substrates, including screen-printed carbon electrodes (SPE) and inkjet-printed graphene electrodes (IJP-Gr). Finally, a biocompatible dropcast polyaniline-modified IJP was selected and paired with an inkjet-printed Ag/AgCl quasireference electrode. The printed potentiometric device showed Nernstian sensitivity (58.8 mV/pH) with good reproducibility, reversibility, and potential stability. The optimized system was integrated with a developed lung-on-a-chip model with an electrospun polycaprolactone membrane and alginate, simulating the alveolar barrier and the natural mucosal environment, respectively. The permeability of the system was studied by monitoring the pH changes upon the introduction of a 10 wt.% acetic acid aerosol. Overall, the presented approach shows that electrospun-hydrogel materials together with integrated microsensors can help create improved models for studying aerosol transport, diffusion, and chemically changing environments that are relevant for inhalation therapy and respiratory research. These results show that our system can combine mechanical behavior with chemical sensing in one platform, which may be useful for future development of lung-on-a-chip technologies. Full article
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22 pages, 2934 KB  
Article
Evaluation of the Antimicrobial Activity of Oregano Essential Oil on the Microbiological Quality of Sea Bream (Sparus aurata) Fillets Under Active Packaging Using Spectroscopic Sensors
by Fotoula Schoina, Stamatina Xenou, Angeliki Doukaki, Symeon Makris, Olga S. Papadopoulou, Chrysoula Tassou, George-John Nychas and Nikos Chorianopoulos
Chemosensors 2026, 14(1), 14; https://doi.org/10.3390/chemosensors14010014 - 2 Jan 2026
Viewed by 285
Abstract
This study evaluated the combined effect of the modified atmosphere packaging (MAP1: 60% CO2, 10% O2/30% N2 & MAP2: 40% CO2, 30% O2/30% N2), and active packaging of oregano essential oil (1% [...] Read more.
This study evaluated the combined effect of the modified atmosphere packaging (MAP1: 60% CO2, 10% O2/30% N2 & MAP2: 40% CO2, 30% O2/30% N2), and active packaging of oregano essential oil (1% v/w) used as a natural preservative, on the quality and shelf-life extension of fresh sea bream fillets. The samples were stored at four different temperatures (0, 4, 8, and 12 °C), and a microbiological analysis, pH measurements, and sensory evaluations were performed. In parallel, spectral data were obtained using three different spectroscopic sensors (two MultiSpectral Imaging devices and an FT-IR one), and nine different machine-learning regression models were applied to predict the microbiological counts. Oregano essential oil positively affected preservation, reducing microbial growth by 0.5 to 2 log CFU/g, and extending the fillets’ shelf life by up to 48 h based on sensory evaluation. Regarding the sensors’ data, the examined nine models exhibited encouraging results for the rapid microbiological assessment, with the FT-IR data showing the best performance for evaluating the microbiological population. Among the tested algorithms, the least Angle Regression (lars) achieved the best performance for both the flesh and skin datasets, with RMSE values of 0.6075 and 0.5953, MAE of 0.3008 and 0.4567, R2 of 0.8858 and 0.7532, and accuracy of 87% and 91%, respectively. The Benchtop-MSI showed the best predictive performance for flesh (RMSE = 0.5926, MAE = 0.4876, R2 = 0.7338, and Accuracy = 92%), while the artificial neural network (nnet) performed best for skin (RMSE = 0.6761, MAE = 0.5247, R2 = 0.6560, and Accuracy = 84%). Regarding the Portable-MSI, the artificial neural network model gave the highest accuracy for flesh (RMSE = 0.5908, MAE = 0.4663, R2 = 0.5903, and Accuracy = 87%), whereas principal component regression was the most effective for skin (RMSE = 0.6600, MAE = 0.5413, R2 = 0.5534, and Accuracy = 83%). Full article
(This article belongs to the Section Optical Chemical Sensors)
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Article
Novel Garlic Carbon Dot-Incorporated Starch Whey Protein Emulsion Gel for Apple Spoilage Sensing
by Hebat-Allah S. Tohamy
Gels 2026, 12(1), 47; https://doi.org/10.3390/gels12010047 - 1 Jan 2026
Viewed by 309
Abstract
This study presents the development of a smart packaging material utilizing garlic-derived nitrogen-doped carbon dots (CDs) integrated into a whey protein–starch (WP-S) emulsion. The research aimed to create a real-time, non-invasive biosensor capable of detecting microbial spoilage. The synthesized CDs demonstrated strong pH-sensitive [...] Read more.
This study presents the development of a smart packaging material utilizing garlic-derived nitrogen-doped carbon dots (CDs) integrated into a whey protein–starch (WP-S) emulsion. The research aimed to create a real-time, non-invasive biosensor capable of detecting microbial spoilage. The synthesized CDs demonstrated strong pH-sensitive photoluminescence, exhibiting distinct changes in CIE coordinates and fluorescence intensity in response to varying pH values. The WP-S-CDs emulsion was tested against E. coli, S. aureus, and C. albicans. The results showed that the composite film provided a clear colorimetric shift and fluorescence quenching, both of which are directly correlated with microbial metabolic activity. The physical and electronic properties of the composite were investigated to understand the sensing mechanism. Scanning electron microscopy (SEM) of the dried film revealed that the WP-S-CDs system formed a more porous structure with larger pore sizes (3.63–8.18 µm) compared to the control WP-S film (1.62–6.52 µm), which facilitated the rapid diffusion of microbial metabolites. Additionally, density functional theory (DFT) calculations demonstrated that the incorporation of CDs significantly enhanced the composite’s electronic properties by reducing its band gap and increasing its dipole moment, thereby heightening its reactivity and sensitivity to spoilage byproducts. In a practical application on apples, the WP-S-CDs coating produced a visible red spot, confirming its function as a dynamic sensor. The material also showed a dual-action antimicrobial effect, synergistically inhibiting C. albicans while exhibiting an antagonistic effect against bacteria. These findings validate the potential of the WP-S-CDs emulsion as a powerful, multi-faceted intelligent packaging system for food quality monitoring. Full article
(This article belongs to the Special Issue Hydrogels for Food Safety and Sensing Applications)
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