The COVID-19 pandemic and recurring outbreaks of infectious diseases underscore the urgent demand for multiplex diagnostics capable of rapid and accurate pathogen identification. Although multiplex nucleic acid amplification tests (NAATs) are widely used for diagnosing diverse infectious diseases, their inherent amplification bias and long turnaround times highlight the demand for faster and reliable alternatives. Here, we present multicolor SATORI (mSATORI), an amplification-free single-molecule genetic test that leverages the complementary activities of CRISPR–Cas13a and Cas13b to achieve simultaneous detection of dual RNA targets. mSATORI identified Influenza A and SARS-CoV-2 RNAs within ∼10 min, with analytical limits of detection (LoD) of 86 aM and 52 aM, respectively. Validation using clinical specimens demonstrated robust diagnostic performance, achieving femtomolar limits of detection (550 aM for Influenza A and 640 aM for SARS-CoV-2), along with sensitivities exceeding 80% and specificities of 100%. Collectively, these results establish mSATORI as a platform for next-generation molecular diagnostics, with broad implications for clinical implementation, outbreak preparedness, and global infectious disease surveillance.
{"title":"Multicolor Amplification-Free RNA Detection with Cas13a and Cas13b","authors":"Hajime Shinoda, Asami Makino, Mami Yoshimura, Noriko Minagawa, Tatsuya Iida, Masahiro Nakano, Takeshi Noda, Masashi Toyoda, Rikiya Watanabe","doi":"10.1021/acs.analchem.5c06305","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c06305","url":null,"abstract":"The COVID-19 pandemic and recurring outbreaks of infectious diseases underscore the urgent demand for multiplex diagnostics capable of rapid and accurate pathogen identification. Although multiplex nucleic acid amplification tests (NAATs) are widely used for diagnosing diverse infectious diseases, their inherent amplification bias and long turnaround times highlight the demand for faster and reliable alternatives. Here, we present multicolor SATORI (mSATORI), an amplification-free single-molecule genetic test that leverages the complementary activities of CRISPR–Cas13a and Cas13b to achieve simultaneous detection of dual RNA targets. mSATORI identified Influenza A and SARS-CoV-2 RNAs within ∼10 min, with analytical limits of detection (LoD) of 86 aM and 52 aM, respectively. Validation using clinical specimens demonstrated robust diagnostic performance, achieving femtomolar limits of detection (550 aM for Influenza A and 640 aM for SARS-CoV-2), along with sensitivities exceeding 80% and specificities of 100%. Collectively, these results establish mSATORI as a platform for next-generation molecular diagnostics, with broad implications for clinical implementation, outbreak preparedness, and global infectious disease surveillance.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"94 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146101940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This study presents a self-powered photoelectrochromic biosensor for the visual, direct-reading detection of 3,3′,4,4′-tetrachlorobiphenyl (PCB-77) based on a distance-based signal readout. The sensor chip integrates a detection zone and an optical channel coated with Prussian blue (PB). In the presence of the target PCB-77, a competitive binding event is triggered that displaces nanozyme-labeled DNA complexes. This reduces the formation of an insulating precipitate on the electrode surface, thereby facilitating the generation and transfer of photogenerated electrons under illumination. The photogenerated electrons reduce PB to Prussian white, creating a bleached zone with a length that can be directly measured. The decoloration length shows a linear relationship with PCB-77 concentration ranging from 4 nM to 5 μM, with a detection limit of 1.14 nM. By translating the electrochemical signal into a measurable distance, this strategy effectively circumvents the subjectivity inherent in traditional colorimetric intensity measurements, offering a robust and portable platform for reliable environmental monitoring.
{"title":"Self-powered Photoelectrochromic Biosensor for Visual Detection Using a Distance-Based Signal Readout","authors":"Jiadong Zhang,Tiantian Hu,Yanchao Dou,Liming Guo,Xiangyu Ma,Nan Hao,Yi Chen","doi":"10.1021/acs.analchem.5c07984","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c07984","url":null,"abstract":"This study presents a self-powered photoelectrochromic biosensor for the visual, direct-reading detection of 3,3′,4,4′-tetrachlorobiphenyl (PCB-77) based on a distance-based signal readout. The sensor chip integrates a detection zone and an optical channel coated with Prussian blue (PB). In the presence of the target PCB-77, a competitive binding event is triggered that displaces nanozyme-labeled DNA complexes. This reduces the formation of an insulating precipitate on the electrode surface, thereby facilitating the generation and transfer of photogenerated electrons under illumination. The photogenerated electrons reduce PB to Prussian white, creating a bleached zone with a length that can be directly measured. The decoloration length shows a linear relationship with PCB-77 concentration ranging from 4 nM to 5 μM, with a detection limit of 1.14 nM. By translating the electrochemical signal into a measurable distance, this strategy effectively circumvents the subjectivity inherent in traditional colorimetric intensity measurements, offering a robust and portable platform for reliable environmental monitoring.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"68 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146111059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-03DOI: 10.1021/acs.analchem.5c07821
Feifan Xiang, Hong Zhang, Dingheng Zhou, Yang Yu, Shanyong Chen, Qian Zhou, Yuanyuan Zhang, Min Wu, Kun Li, Xiaoqi Yu
Alzheimer's disease (AD), a progressive neurodegenerative disorder, represents a major global health challenge for aging populations. As amyloid-β (Aβ) plaques are pathological hallmarks of AD, their efficient detection is critical for disease staging and early diagnosis. However, existing fluorescent probes are hindered by a weak signal response to Aβ plaques, short-emission wavelengths, and insufficient blood-brain barrier (BBB) penetration, which preclude effective in vivo imaging. To address these limitations, we developed a novel series of second near-infrared window (NIR-II) probes, termed CoR-Aβs, engineered for high-affinity binding to Aβ fibrils. Demonstrating exceptional BBB permeability, our lead compound, CoR-Aβ-4, enables real-time dynamic tracking of plaque deposition in vivo. This work establishes NIR-II fluorescent probes as a transformative platform for advancing diagnostic strategies in neurodegenerative disease intervention.
阿尔茨海默病(AD)是一种进行性神经退行性疾病,是全球老龄化人口面临的主要健康挑战。淀粉样蛋白-β (Aβ)斑块是阿尔茨海默病的病理标志,其有效检测对疾病分期和早期诊断至关重要。然而,现有的荧光探针受到a β斑块信号响应弱、发射波长短和血脑屏障(BBB)穿透不足的阻碍,这妨碍了有效的体内成像。为了解决这些限制,我们开发了一系列新的第二近红外窗口(NIR-II)探针,称为co -a - βs,设计用于与β原纤维高亲和力结合。我们的先导化合物co - a - β-4显示出卓越的血脑屏障渗透性,可以实时动态跟踪体内斑块沉积。这项工作建立了NIR-II荧光探针作为推进神经退行性疾病干预诊断策略的变革性平台。
{"title":"Dynamic Visualization of Amyloid-β Plaques with a Novel NIR-II Fluorescence Reporter.","authors":"Feifan Xiang, Hong Zhang, Dingheng Zhou, Yang Yu, Shanyong Chen, Qian Zhou, Yuanyuan Zhang, Min Wu, Kun Li, Xiaoqi Yu","doi":"10.1021/acs.analchem.5c07821","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c07821","url":null,"abstract":"<p><p>Alzheimer's disease (AD), a progressive neurodegenerative disorder, represents a major global health challenge for aging populations. As amyloid-β (Aβ) plaques are pathological hallmarks of AD, their efficient detection is critical for disease staging and early diagnosis. However, existing fluorescent probes are hindered by a weak signal response to Aβ plaques, short-emission wavelengths, and insufficient blood-brain barrier (BBB) penetration, which preclude effective in vivo imaging. To address these limitations, we developed a novel series of second near-infrared window (NIR-II) probes, termed CoR-Aβs, engineered for high-affinity binding to Aβ fibrils. Demonstrating exceptional BBB permeability, our lead compound, CoR-Aβ-4, enables real-time dynamic tracking of plaque deposition in vivo. This work establishes NIR-II fluorescent probes as a transformative platform for advancing diagnostic strategies in neurodegenerative disease intervention.</p>","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":" ","pages":""},"PeriodicalIF":6.7,"publicationDate":"2026-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146103094","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Accurate detection of micro- and macrocancer lesions remains a critical challenge in histopathology, as conventional hematoxylin and eosin staining requires labor-intensive analysis and is limited in sensitivity toward microscopic foci. Here, we present an artificial intelligence (AI)-assisted workflow integrating Fourier transform infrared (FT-IR) hyperspectral imaging with chemometric modeling for enhanced cancer screening in lung tissues. Using a focal-plane array (128 × 128 pixels with a pixel projection of 5.5 μm × 5.5 μm), hyperspectral maps were generated, enabling biochemical characterization of distinct morphological structures, including bronchial and vascular walls, parenchyma, and neoplastic regions. Histopathological annotations were employed to construct calibration data sets for noncancerous tissues, microcancer lesions, and macrocancer lesions. Discriminant analysis revealed high predictive accuracy across validation strategies, with CORRS-CV (δ = 5) outperforming conventional k-fold and image-based approaches (AUROC = 0.94, accuracy = 97%, and specificity = 98%). This robust performance reflects reduced cross-validation bias and improved generalizability of predictive models. Importantly, FT-IR imaging enabled the detection of both macro- and microlesions consistent with histological references, while also revealing spectral similarities in vascular walls that occasionally led to false-positive predictions. Together, these findings demonstrated that AI-assisted FT-IR chemometrics offers the rapid, label-free, and spatially resolved detection of cancer lesions, complementing standard histopathology by improving sensitivity to microscopic disease and supporting stratification of tumor progression.
{"title":"Artificial Intelligence-Assisted Infrared Spectroscopy and Chemometrics for Enhanced Histopathology Screening of Micro- and Macrocancer Lesions","authors":"Karolina Chrabaszcz,Guillermo Quintas,Julia Kuligowski,Kamilla Malek","doi":"10.1021/acs.analchem.5c06870","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c06870","url":null,"abstract":"Accurate detection of micro- and macrocancer lesions remains a critical challenge in histopathology, as conventional hematoxylin and eosin staining requires labor-intensive analysis and is limited in sensitivity toward microscopic foci. Here, we present an artificial intelligence (AI)-assisted workflow integrating Fourier transform infrared (FT-IR) hyperspectral imaging with chemometric modeling for enhanced cancer screening in lung tissues. Using a focal-plane array (128 × 128 pixels with a pixel projection of 5.5 μm × 5.5 μm), hyperspectral maps were generated, enabling biochemical characterization of distinct morphological structures, including bronchial and vascular walls, parenchyma, and neoplastic regions. Histopathological annotations were employed to construct calibration data sets for noncancerous tissues, microcancer lesions, and macrocancer lesions. Discriminant analysis revealed high predictive accuracy across validation strategies, with CORRS-CV (δ = 5) outperforming conventional k-fold and image-based approaches (AUROC = 0.94, accuracy = 97%, and specificity = 98%). This robust performance reflects reduced cross-validation bias and improved generalizability of predictive models. Importantly, FT-IR imaging enabled the detection of both macro- and microlesions consistent with histological references, while also revealing spectral similarities in vascular walls that occasionally led to false-positive predictions. Together, these findings demonstrated that AI-assisted FT-IR chemometrics offers the rapid, label-free, and spatially resolved detection of cancer lesions, complementing standard histopathology by improving sensitivity to microscopic disease and supporting stratification of tumor progression.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"275 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146097933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-02DOI: 10.1021/acs.analchem.5c05792
Anniek L. de Jager, Sara Kassem, Louis Alesha, Brigitta A.E. Naber, Inge F. de Laat, Bas de Mooij, Kyra van der Pan, Erik Bos, Roman I. Koning, Jacques J.M. van Dongen, Cristina Teodosio, Paula Díez
Lysosomes, essential organelles involved in diverse cellular processes, are increasingly recognized as central players in the pathogenesis of numerous diseases. Due to their low abundance in whole-cell extracts, enrichment strategies are required for downstream analyses such as proteomics. Despite the availability of various lysosome isolation methods, including density gradient-based separation, filter-based approaches, magnetic bead-based isolation, and subcellular fractionation, a systematic, multimodal comparison of their performance is lacking. Here, four widely used lysosome enrichment techniques are benchmarked using the THP-1 monocytic cell line as a model. Each method has been evaluated for yield, purity, membrane integrity, reproducibility, scalability, and cross-contamination, employing nanoparticle tracking analysis, electron microscopy, flow cytometry, Western blotting, and mass spectrometry-based proteomics. Data reveal substantial differences: gradient-based and bead-based methods provide the highest lysosomal enrichment and proteomic purity, whereas the subcellular fractionation approach yields greater numbers of lysosomes but with increased variability and contamination. Finally, the filter-based method enables rapid processing, but mainly nonintact lysosomes are obtained with significant cross-contamination. These findings provide practical guidance for selecting the appropriate lysosome enrichment strategy, tailored to specific research or clinical objectives. The results also emphasize the need for rigorous validation to ensure the robustness of lysosomal studies in both basic and clinical research settings.
{"title":"Benchmarking Lysosome Enrichment Methods: A Guide for Research and Clinical Translation","authors":"Anniek L. de Jager, Sara Kassem, Louis Alesha, Brigitta A.E. Naber, Inge F. de Laat, Bas de Mooij, Kyra van der Pan, Erik Bos, Roman I. Koning, Jacques J.M. van Dongen, Cristina Teodosio, Paula Díez","doi":"10.1021/acs.analchem.5c05792","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c05792","url":null,"abstract":"Lysosomes, essential organelles involved in diverse cellular processes, are increasingly recognized as central players in the pathogenesis of numerous diseases. Due to their low abundance in whole-cell extracts, enrichment strategies are required for downstream analyses such as proteomics. Despite the availability of various lysosome isolation methods, including density gradient-based separation, filter-based approaches, magnetic bead-based isolation, and subcellular fractionation, a systematic, multimodal comparison of their performance is lacking. Here, four widely used lysosome enrichment techniques are benchmarked using the THP-1 monocytic cell line as a model. Each method has been evaluated for yield, purity, membrane integrity, reproducibility, scalability, and cross-contamination, employing nanoparticle tracking analysis, electron microscopy, flow cytometry, Western blotting, and mass spectrometry-based proteomics. Data reveal substantial differences: gradient-based and bead-based methods provide the highest lysosomal enrichment and proteomic purity, whereas the subcellular fractionation approach yields greater numbers of lysosomes but with increased variability and contamination. Finally, the filter-based method enables rapid processing, but mainly nonintact lysosomes are obtained with significant cross-contamination. These findings provide practical guidance for selecting the appropriate lysosome enrichment strategy, tailored to specific research or clinical objectives. The results also emphasize the need for rigorous validation to ensure the robustness of lysosomal studies in both basic and clinical research settings.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"87 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146101942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Cascade nanozymes for biosensing are fundamentally hampered by diffusion limitations and passive catalytic sites. Herein, we report a strategy of electrochemical gating of d-band engineering within a hierarchically bridged dual-site nanozyme (CuNCs@FeMOP) to achieve dynamic control over cascading catalysis. This architecture spatially confines the ascorbic acid oxidase-mimicking copper nanocluster (CuNC) core and the peroxidase-mimicking iron-based microporous organic polymer (FeMOP) shell, eliminating intermediate diffusion losses. More critically, synergistic electronic coupling via a histidine bridge provides static preoptimization of the Cu and Fe sites’ d-band structure, enhancing their intrinsic activities. Upon this foundation, an external electric field acts as a dynamic gate, further modulating the d-band centers of both Cu and Fe sites to synchronously amplify their respective catalytic activities. This dual-mode d-band engineering endows the CuNCs@FeMOP system with exceptional Michaelis–Menten kinetics (low Km, high Vmax) far surpassing conventional mixed-catalyst systems. The nanozyme was integrated into a flexible patch for the real-time, colorimetric/electrochemical dual-mode monitoring of ascorbic acid in human sweat, demonstrating its practical utility. This work introduces a paradigm for catalyst design, where gated d-band engineering in bridged, multisite architectures enables programmable control over catalytic processes for advanced wearable diagnostics.
{"title":"Electrochemical Gating of d-Band Engineering in Hierarchically Bridged Dual-Site Nanozymes for Synergistic Cascade Catalysis and Wearable Biosensing","authors":"Huining Chai, Xi Sun, Xiao Tan, Zhishuang Yuan, Jing Guan, Xueji Zhang, Jianping Xie, Guangyao Zhang","doi":"10.1021/acs.analchem.5c06201","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c06201","url":null,"abstract":"Cascade nanozymes for biosensing are fundamentally hampered by diffusion limitations and passive catalytic sites. Herein, we report a strategy of electrochemical gating of d-band engineering within a hierarchically bridged dual-site nanozyme (CuNCs@FeMOP) to achieve dynamic control over cascading catalysis. This architecture spatially confines the ascorbic acid oxidase-mimicking copper nanocluster (CuNC) core and the peroxidase-mimicking iron-based microporous organic polymer (FeMOP) shell, eliminating intermediate diffusion losses. More critically, synergistic electronic coupling via a histidine bridge provides static preoptimization of the Cu and Fe sites’ d-band structure, enhancing their intrinsic activities. Upon this foundation, an external electric field acts as a dynamic gate, further modulating the d-band centers of both Cu and Fe sites to synchronously amplify their respective catalytic activities. This dual-mode d-band engineering endows the CuNCs@FeMOP system with exceptional Michaelis–Menten kinetics (low <i>K</i><sub>m</sub>, high <i>V</i><sub>max</sub>) far surpassing conventional mixed-catalyst systems. The nanozyme was integrated into a flexible patch for the real-time, colorimetric/electrochemical dual-mode monitoring of ascorbic acid in human sweat, demonstrating its practical utility. This work introduces a paradigm for catalyst design, where gated d-band engineering in bridged, multisite architectures enables programmable control over catalytic processes for advanced wearable diagnostics.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"5 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146097806","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nanozymes feature structural stability, functional diversity, and tunable activity, demonstrating promise in enzyme-nanozyme cascade systems for small molecule detection. However, the cascade performance is typically hindered by pH incompatibility and the cumbersome preparation of nanozymes. Herein, copper-doped zeolitic imidazolate framework-90 (Cu/Zn-ZIF-90) was developed through a facile synthesis within 10 min of reaction, which was established as a promising ascorbate peroxidase (APX)-like nanozyme for pH-adaptive cascades. Cu/Zn-ZIF-90 oxidizes ascorbic acid using H2O2 as cosubstrate and demonstrates higher affinity for H2O2 than most APX-like or POD-like nanozymes, enabling effective intermediate conversion in cascade reactions. Notably, Cu/Zn-ZIF-90 nanozyme exhibits optimal activity under neutral pH, resolving pH mismatch when coupled with acid-denatured oxidases. As proof of concept, we integrated APX-like Cu/Zn-ZIF-90 with choline oxidase to develop a one-step cascade fluorescence biosensor for choline detection. The sensor achieved a broad linear range (1–1000 μM) and a low detection limit (0.85 μM), outperforming most existing methods while demonstrating robust applicability in the analysis of complex food matrices. This work establishes APX-mimicking nanozymes as key components to overcome cascade pH barriers, enabling one-step small-molecule biosensing.
{"title":"Facile Synthesis of pH-Adaptive Ascorbate Peroxidase-like Nanozyme for One-Step Enzyme-Nanozyme Cascade Biosensing","authors":"Huifang Zhang, Yuhang Zhang, Xiang Xu, Hanqiang Zhang, Xiaoming Ma, Yuexiang Li, Longhua Guo","doi":"10.1021/acs.analchem.5c06320","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c06320","url":null,"abstract":"Nanozymes feature structural stability, functional diversity, and tunable activity, demonstrating promise in enzyme-nanozyme cascade systems for small molecule detection. However, the cascade performance is typically hindered by pH incompatibility and the cumbersome preparation of nanozymes. Herein, copper-doped zeolitic imidazolate framework-90 (Cu/Zn-ZIF-90) was developed through a facile synthesis within 10 min of reaction, which was established as a promising ascorbate peroxidase (APX)-like nanozyme for pH-adaptive cascades. Cu/Zn-ZIF-90 oxidizes ascorbic acid using H<sub>2</sub>O<sub>2</sub> as cosubstrate and demonstrates higher affinity for H<sub>2</sub>O<sub>2</sub> than most APX-like or POD-like nanozymes, enabling effective intermediate conversion in cascade reactions. Notably, Cu/Zn-ZIF-90 nanozyme exhibits optimal activity under neutral pH, resolving pH mismatch when coupled with acid-denatured oxidases. As proof of concept, we integrated APX-like Cu/Zn-ZIF-90 with choline oxidase to develop a one-step cascade fluorescence biosensor for choline detection. The sensor achieved a broad linear range (1–1000 μM) and a low detection limit (0.85 μM), outperforming most existing methods while demonstrating robust applicability in the analysis of complex food matrices. This work establishes APX-mimicking nanozymes as key components to overcome cascade pH barriers, enabling one-step small-molecule biosensing.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"145 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146097808","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Early detection of breast cancer remains challenging due to limitations of current screening methods, including reduced sensitivity in dense tissue, false positives that lead to additional imaging and invasive biopsies. Untargeted metabolomics using noninvasive matrices such as urine has emerged as a promising complementary approach. In this study, a voltammetric electronic tongue consisting of 12 sensors, bare and modified with three isomeric conjugated polymers, was developed to transduce urinary metabolomic differences into electrochemical fingerprints. Performance was first evaluated on artificial urine and then tested on a larger set of clinical specimens. Differential pulse voltammetry signals were preprocessed to reduce dimensionality, analyzed by PCA and PLS-DA for pattern recognition and outlier detection, and classified into cancer and control groups using a range of linear, nonlinear, and ensemble-based supervised learning. On artificial urine, PCA showed clear separation, and gradient boosting achieved the highest test accuracy (96%). In clinical urine, separation by PCA was less pronounced, whereas PLS-DA and supervised models improved discrimination, with gradient boosting yielding 97% accuracy. Overall, the results show that the proposed electronic tongue captures clinically relevant urinary signatures and that supervised methods are advantageous when moving from artificial to real-world samples.
{"title":"Conjugated-Polymer-Based Electronic Tongue for Breast Cancer Discrimination: from Artificial to Clinical Urine Samples","authors":"Parastoo Vahdatiyekta, Nicodemus Kraufvelin, Lucie Legrand, Pauline Brunet, Emilia Ares, Manel del Valle, Tan-Phat Huynh","doi":"10.1021/acs.analchem.5c07243","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c07243","url":null,"abstract":"Early detection of breast cancer remains challenging due to limitations of current screening methods, including reduced sensitivity in dense tissue, false positives that lead to additional imaging and invasive biopsies. Untargeted metabolomics using noninvasive matrices such as urine has emerged as a promising complementary approach. In this study, a voltammetric electronic tongue consisting of 12 sensors, bare and modified with three isomeric conjugated polymers, was developed to transduce urinary metabolomic differences into electrochemical fingerprints. Performance was first evaluated on artificial urine and then tested on a larger set of clinical specimens. Differential pulse voltammetry signals were preprocessed to reduce dimensionality, analyzed by PCA and PLS-DA for pattern recognition and outlier detection, and classified into cancer and control groups using a range of linear, nonlinear, and ensemble-based supervised learning. On artificial urine, PCA showed clear separation, and gradient boosting achieved the highest test accuracy (96%). In clinical urine, separation by PCA was less pronounced, whereas PLS-DA and supervised models improved discrimination, with gradient boosting yielding 97% accuracy. Overall, the results show that the proposed electronic tongue captures clinically relevant urinary signatures and that supervised methods are advantageous when moving from artificial to real-world samples.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"292 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146097810","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Accurate and reliable nitrite (NO2–) detection is crucial for food safety but remains challenging. Herein, we develop a triple-signal sensing strategy utilizing bifunctional carbon dot (CD) nanozymes for NO2– analysis in diverse food matrices. CDs with blue fluorescence and photoresponsive oxidase-mimicking activity are successfully synthesized by a simple one-step hydrothermal treatment with citric acid monohydrate (CA) and triethanolamine (TEA) as precursors. The oxidase-mimicking property enables efficient catalytic oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) from colorless to blue ox-TMB. Capitalizing on the specific diazotization reaction between NO2– and o-phenylenediamine (OPD)/ox-TMB, the engineered sensor delivers ratiometric fluorescence, ratiometric colorimetric, and photothermal triple-signal outputs, displaying high performance in selectivity and anti-interference capability. The linear detection ranges for NO2– are 0.5–400 μM in ratiometric fluorescence sensing, 0.5–100 μM in ratiometric colorimetric sensing, and 5–100 μM in photothermal sensing, with corresponding limits of detection of 0.23 μM, 0.19 μM, and 1.43 μM, respectively. Furthermore, by leveraging the distinct color transitions from ratiometric fluorescence and colorimetric responses, a dual-modality sensing platform assisted by smartphones is engineered to achieve convenient, visual, and on-site NO2– detection in food samples. Notably, the integrated photothermal detection specifically overcomes the limitations of conventional optical methods for analyzing colored or autofluorescent samples, while the cross-validation capability of the multimodal strategy ensures reliable and stable results. This synergy provides a comprehensive and promising solution for the accurate and robust monitoring of NO2– in multiple types of food matrices.
{"title":"Bifunctional Carbon Dot Nanozymes for Ratiometric Optical, Photothermal, and Smartphone-Assisted Multimodal Detection of Nitrite","authors":"Jianan Pei, Jiayi Li, Yuhui Guo, Shaomin Shuang, Dan Chang, Yuan Zhang, Chuan Dong","doi":"10.1021/acs.analchem.5c07104","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c07104","url":null,"abstract":"Accurate and reliable nitrite (NO<sub>2</sub><sup>–</sup>) detection is crucial for food safety but remains challenging. Herein, we develop a triple-signal sensing strategy utilizing bifunctional carbon dot (CD) nanozymes for NO<sub>2</sub><sup>–</sup> analysis in diverse food matrices. CDs with blue fluorescence and photoresponsive oxidase-mimicking activity are successfully synthesized by a simple one-step hydrothermal treatment with citric acid monohydrate (CA) and triethanolamine (TEA) as precursors. The oxidase-mimicking property enables efficient catalytic oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) from colorless to blue ox-TMB. Capitalizing on the specific diazotization reaction between NO<sub>2</sub><sup>–</sup> and <i>o</i>-phenylenediamine (OPD)/ox-TMB, the engineered sensor delivers ratiometric fluorescence, ratiometric colorimetric, and photothermal triple-signal outputs, displaying high performance in selectivity and anti-interference capability. The linear detection ranges for NO<sub>2</sub><sup>–</sup> are 0.5–400 μM in ratiometric fluorescence sensing, 0.5–100 μM in ratiometric colorimetric sensing, and 5–100 μM in photothermal sensing, with corresponding limits of detection of 0.23 μM, 0.19 μM, and 1.43 μM, respectively. Furthermore, by leveraging the distinct color transitions from ratiometric fluorescence and colorimetric responses, a dual-modality sensing platform assisted by smartphones is engineered to achieve convenient, visual, and on-site NO<sub>2</sub><sup>–</sup> detection in food samples. Notably, the integrated photothermal detection specifically overcomes the limitations of conventional optical methods for analyzing colored or autofluorescent samples, while the cross-validation capability of the multimodal strategy ensures reliable and stable results. This synergy provides a comprehensive and promising solution for the accurate and robust monitoring of NO<sub>2</sub><sup>–</sup> in multiple types of food matrices.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"16 2 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146097811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-02-02DOI: 10.1021/acs.analchem.5c07283
Nuria Martínez-Lorca, Yujie Liu, Gregorio Laucirica, Gastón A. Crespo, María Cuartero
Herein, we investigate all-solid-state ion-selective electrodes (ISEs) based on permselective nanomembranes (thickness ∼230 nm) in a coulometric mode. The detection of the potassium ion (K+) has been selected as proof of concept, implementing two electrochemical protocols based on the anodic and cathodic readouts of the same ISE. The electrode consists of an ITO glass substrate with the conducting polymer poly(3-octylthiophene) (POT) electrodeposited on it and a potassium-selective nanomembrane spin-coated over the POT layer. The K+ transfer at the membrane-sample interface is mediated by the redox activity of POT, which is in excess with respect to the dopant in the membrane (i.e., the anion part of the cation exchanger, R–). In the cathodic protocol, the entry of the K+ into the membrane is promoted by the POT+ reduction to POT0; while in the anodic interrogation, first, K+ enters the membrane with a previous accumulation step, and then it is expelled during the oxidation of the POT0 to POT+. Both protocols were studied under linear sweep voltammetry and chronoamperometry, followed by signal integration to obtain the charge corresponding to K+. It is demonstrated that this charge is directly proportional to the K+ concentration in the bulk solution. We found two distinct response ranges: 3–20 μM in the cathodic protocol and 200–1000 nM in the anodic one. In addition, the cathodic coulometry strategy revealed excellent repeatability and reversibility within the linear range of response. The developed analytical approach demonstrates suitability in the quantification of real samples, i.e., human urine, horse serum, canal water, and standard KCl solution, while providing a linear and tunable coulometric response over a broad concentration range from the nanomolar to the micromolar level. Moreover, the sensor can be readily integrated into microfluidic devices, additionally offering the advantage of small sample volume requirements. The demonstrated reversibility, along with the ability to customize the ionophore in the membrane for an analysis of different ions, renders the proposed concept adaptable and exceptionally suitable for clinical analysis and environmental monitoring.
{"title":"Tunable Ion-Sensing Using Coulometric-Based Protocols with Permselective Nanomembranes","authors":"Nuria Martínez-Lorca, Yujie Liu, Gregorio Laucirica, Gastón A. Crespo, María Cuartero","doi":"10.1021/acs.analchem.5c07283","DOIUrl":"https://doi.org/10.1021/acs.analchem.5c07283","url":null,"abstract":"Herein, we investigate all-solid-state ion-selective electrodes (ISEs) based on permselective nanomembranes (thickness ∼230 nm) in a coulometric mode. The detection of the potassium ion (K<sup>+</sup>) has been selected as proof of concept, implementing two electrochemical protocols based on the anodic and cathodic readouts of the same ISE. The electrode consists of an ITO glass substrate with the conducting polymer poly(3-octylthiophene) (POT) electrodeposited on it and a potassium-selective nanomembrane spin-coated over the POT layer. The K<sup>+</sup> transfer at the membrane-sample interface is mediated by the redox activity of POT, which is in excess with respect to the dopant in the membrane (i.e., the anion part of the cation exchanger, R<sup>–</sup>). In the cathodic protocol, the entry of the K<sup>+</sup> into the membrane is promoted by the POT<sup>+</sup> reduction to POT<sup>0</sup>; while in the anodic interrogation, first, K<sup>+</sup> enters the membrane with a previous accumulation step, and then it is expelled during the oxidation of the POT<sup>0</sup> to POT<sup>+</sup>. Both protocols were studied under linear sweep voltammetry and chronoamperometry, followed by signal integration to obtain the charge corresponding to K<sup>+</sup>. It is demonstrated that this charge is directly proportional to the K<sup>+</sup> concentration in the bulk solution. We found two distinct response ranges: 3–20 μM in the cathodic protocol and 200–1000 nM in the anodic one. In addition, the cathodic coulometry strategy revealed excellent repeatability and reversibility within the linear range of response. The developed analytical approach demonstrates suitability in the quantification of real samples, i.e., human urine, horse serum, canal water, and standard KCl solution, while providing a linear and tunable coulometric response over a broad concentration range from the nanomolar to the micromolar level. Moreover, the sensor can be readily integrated into microfluidic devices, additionally offering the advantage of small sample volume requirements. The demonstrated reversibility, along with the ability to customize the ionophore in the membrane for an analysis of different ions, renders the proposed concept adaptable and exceptionally suitable for clinical analysis and environmental monitoring.","PeriodicalId":27,"journal":{"name":"Analytical Chemistry","volume":"82 1","pages":""},"PeriodicalIF":7.4,"publicationDate":"2026-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146097813","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}