Sensors and Actuators B: Chemical最新文献

{"title":"Rapid identification of sulfur defect levels in MoS₂ and MoSe₂ nanomaterials and their reaction with thiol molecules through defect-induced dimerization of 5-thio-2-nitrobenzoic acid","authors":"S. Santhoshkumar ,&nbsp;Yu-Chan Wu ,&nbsp;Liu Bo-Yu ,&nbsp;Wei-Lung Tseng","doi":"10.1016/j.snb.2026.139577","DOIUrl":"10.1016/j.snb.2026.139577","url":null,"abstract":"<div><div>Several spectroscopic and electron microscopic techniques can monitor sulfur defects in molybdenum disulfide (MoS₂)-based nanomaterials, but they often require costly instrumentation. Herein, we introduce a straightforward, fast, colorimetric method to evaluate sulfur vacancy degree in MoS₂ nanoflowers (NFs), MoS₂ nanosheets (NSs), and molybdenum diselenide (MoSe₂) NSs by monitoring the dimerization of 5-thio-2-nitrobenzoic acid (TNB) into 5,5’-dithiobis(2-nitrobenzoic acid) (DTNB). This sulfur-vacancy-mediated reaction results in a decrease in TNB absorbance at 412 nm and the emergence of a new DTNB peak near 325 nm. The dimerization of TNB triggered by MoS₂ NFs, MoS₂ NSs, and MoSe₂ NSs follows pseudo-first-order kinetics. The rate constants of these materials correlate positively with sulfur defect density, but their maximum absorption capability remains similar. Additionally, machine learning simulations (Open Catalyst Project, GemNet-T) show that the adsorption energy of CH₃SH (a model thiol) becomes more negative with increasing sulfur vacancies on the MoS₂ surface. The MoS₂-mediated TNB dimerization system provides a simple platform to distinguish whether a thiol compound undergoes dimerization or attaches to sulfur defect sites in the presence of sulfur-defective MoS₂. For example, cysteine, glutathione, and homocysteine undergo dimerization, whereas 3-sulfanylpropanoic acid, 4-aminothiophenol, and 2-sulfanylbenzoic acid primarily attach to the sulfur defect sites.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139577"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089614","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}

{"title":"Smartphone-based disposable cotton-swab sensor loaded with creatinine/Cu–chlorophyllin–stabilized AuNPs for ultrasensitive RGB colorimetric detection of mercury (II) ions in aquatic environments","authors":"Natee Lerdpiriyaskulkij ,&nbsp;Ekarat Detsri ,&nbsp;Saowapak Teerasong ,&nbsp;Sarayute Chansai ,&nbsp;Arjnarong Mathaweesansurn","doi":"10.1016/j.snb.2026.139592","DOIUrl":"10.1016/j.snb.2026.139592","url":null,"abstract":"<div><div>A simple, rapid, selective, and sensitive colorimetric sensor based on a disposable cotton swab loaded with Au nanoparticle–modified Cu-chlorophyllin (Au⁰–NPs_CHL) and creatinine was developed for mercury (II) detection in aquatic environments using smartphone–based RGB analysis. Au⁰–NPs_CHL were synthesized by ultrasonic-assisted chemical reduction, employing Cu-chlorophyllin as a stabilizing and NaBH₄ as a reducing agent. A vivid red Au⁰–NPs_CHL colloidal (7.96 ± 0.29 nm) with a sharp SPR peak at 515 nm was successfully obtained. An aliquot of 75 µL of Au⁰-NPs_CHL (0.103 ± 0.03 nmol L⁻¹) and 25 µL of creatinine solution (40 mg L⁻¹) were sequentially loaded into an 8.0 × 0.5 cm cotton swab, separated by a 0.5 cm air gap. Detection began by immersing the swab into Hg²⁺–contaminated samples for 3 min, allowing Hg²⁺ adsorption. Breaking the swab generated pressure differential, which, along with gravity, drove the Au⁰–NPs_CHL to mix with creatinine. The resulting mixture migrated toward the swab tip by capillary action and reacted with adsorbed Hg²⁺ through metallophilic 5d¹⁰–5d¹⁰ interactions. Creatinine acted as a bridging ligand, inducing Au⁰–NPs_CHL aggregation and shifting the SPR to 620 nm, causing a visible red-to-blue transition. This sensor enables rapid and visual detection and quantitative evaluation via smartphone RGB analysis. The system demonstrated excellent linearity from 1 to 100 µg L⁻¹ with a low LOD of 0.82 µg L⁻¹. Recoveries of 97.6–101.8 % confirmed high accuracy and minimal matrix interference. The disposable cotton swab RGB sensor provides a rapid, portable, and practical tool for on-site primary assessment of Hg²⁺ contamination in environmental samples.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139592"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146111018","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}

{"title":"Mode-mismatched photothermal lens-based trace furfural detection using a quantum cascade laser as excitation source","authors":"Fuping Zeng ,&nbsp;Xianzong Chao ,&nbsp;Ruotong Xiong,&nbsp;Langlang Lv,&nbsp;Wei Liu","doi":"10.1016/j.snb.2026.139597","DOIUrl":"10.1016/j.snb.2026.139597","url":null,"abstract":"<div><div>In this paper, a mode-mismatched photothermal lens liquid sensing system using a distributed feedback quantum cascade laser (DFB-QCL) as the excitation source for the detection of furfural in insulating oil. The mid-infrared absorption spectrum of furfural in an insulating oil matrix was characterized by Fourier transform infrared (FTIR) spectroscopy, identifying the optimal absorption peak at 1703 cm⁻¹ . Temperature and current tuning of the DFB-QCL were performed on pure oil and a 500 mg/L furfural/insulating oil sample to determine the optimal temperature and current values, ensuring maximum sensitivity during light excitation of the oil samples. Frequency-domain investigation of the PTL signal response revealed an exponential decrease in signal amplitude with increasing modulation frequency. The PTL signal amplitude exhibited a linear correlation with furfural concentration in the insulating oil. The sensing system has a low limit of detection (LOD) for furfural in insulating oil down to 5.9 mg/L, with a linear concentration range extending up to 500 mg/L. This method does not require pretreatment of the oil sample and can be used for real-time in-situ monitoring.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139597"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146111016","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}

{"title":"Dynamic visualization of butyrylcholinesterase activity in neuroinflammation and Alzheimer's disease with an activatable near-infrared fluorogenic probe","authors":"Wei Peng ,&nbsp;Jiaxin Zhang ,&nbsp;Zheng Wen ,&nbsp;Mengyue Liu ,&nbsp;Bishan Ye ,&nbsp;Xiaopo Zhang ,&nbsp;Fei Wang ,&nbsp;Heng Liu ,&nbsp;Fabiao Yu","doi":"10.1016/j.snb.2026.139615","DOIUrl":"10.1016/j.snb.2026.139615","url":null,"abstract":"<div><div>Alzheimer's disease (AD) is a neurodegenerative disorder characterized by progressive memory loss and cognitive impairment, with neuroinflammation and cholinergic dysfunction playing pivotal roles in its pathological progression. Butyrylcholinesterase (BChE), beyond its hydrolytic function in the periphery, is markedly upregulated in the brains of patients with mid to late-stage AD. However, real-time visualization of BChE activity in neuroinflammatory and AD models remains challenging due to the limited availability of imaging probes that combine high selectivity with efficient blood-brain barrier (BBB) permeability. In this work, an activatable near-infrared fluorogenic (NIRF) probe, DCICF₃-CP, was designed and synthesized for <em>in vivo</em> imaging of BChE activity in neuroinflammatory and AD models. This probe employed dicyanoisophorone (DCI) as its near-infrared fluorophore and incorporated a cyclopropyl ester as a BChE-specific recognition unit. Concurrently, trifluoromethyl groups were introduced onto the aromatic ring to enhance lipophilicity and facilitate BBB permeability. Upon BChE hydrolysis, the cyclopropyl was cleaved, releasing the product DCICF₃, enabling a turn-on fluorescence response. Cellular studies demonstrated that DCICF₃-CP could track BChE upregulation in glutamate- and Aβ₄₂-induced AD-related models. <em>In vivo</em> imaging further revealed significantly elevated BChE activity in LPS-induced neuroinflammatory mice, with decreased fluorescence signals following atorvastatin (Atv) intervention, indicating Atv treatment mitigated neuroinflammation. Moreover, imaging results from AD transgenic mice showed a gradual increase in brain BChE activity with age, consistent with Western blot analysis. Collectively, the developed DCICF₃-CP was suitable for real-time visualization of BChE-related neuroinflammation and AD pathological processes, providing a novel tool for studying the mechanisms of neurodegenerative diseases and evaluating therapeutic interventions.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139615"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146122354","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}

{"title":"Metal organic frameworks-based sensor for visual monitoring of cortisol in human fluids","authors":"Lei Pan ,&nbsp;Qipeng Zhang ,&nbsp;Fan Yang ,&nbsp;Dan Lin ,&nbsp;Changlong Jiang","doi":"10.1016/j.snb.2026.139605","DOIUrl":"10.1016/j.snb.2026.139605","url":null,"abstract":"<div><div>Multi-emission metal organic framework (Eu-MOF) fluorescence probe was designed and prepared as a non-invasive fluorescent sensor, for visual detection of cortisol (CORT) in human fluids. Eu-MOF probes were synthesized by the coordination polymerization of Eu^3 + with 1,3,5-tri(4-carboxyphenyl)benzene (H₃BTB). Under the excitation of 338 nm, Eu-MOF displayed red fluorescence with ultraviolet light. Upon addition of cortisol, the red fluorescence gradually turned blue. CORT tended to attach at the Eu-MOF interface facilitated by strong interaction and potentially formed Eu-MOF-CORT composites. The detection limit (LOD) of the probe was 0.1 nM. The application of the fluorescence sensor is expanded by capturing the color signals with the smartphone camera and analyzed using a color recognition application (APP), through a smartphone contacted with the sensing region on the probe under the UV light. The recovery of fluid samples was ranged from 96.1 % to 101.3 %. Eu-MOF probe-based fluorescence sensor for enable non-invasive visual monitoring of the CORT in human fluids, highlighting the promise of functionalized MOF fluorescence sensors in health monitoring.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139605"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146129437","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}

{"title":"Electrochemical nanopore sensors based on versatile zeolites achieve the discrimination and selective rapid detection of bisphenol structural analogues","authors":"Lin Wang ,&nbsp;Xinbao Zhang ,&nbsp;Yuxi Jiao ,&nbsp;Mengqiong Zhang ,&nbsp;Xinyan Liu ,&nbsp;Xiujie Li ,&nbsp;Xiangxue Zhu ,&nbsp;Shuang Han ,&nbsp;Haijun Zhang ,&nbsp;Jiping Chen ,&nbsp;Lidong Wu ,&nbsp;Xianbo Lu","doi":"10.1016/j.snb.2026.139619","DOIUrl":"10.1016/j.snb.2026.139619","url":null,"abstract":"<div><div>Discriminating and selective detection of structurally similar multi-analytes remains a major challenge in chemical sensing due to severe cross-response interference from shared molecular skeletons and functional groups. To address this, we report a novel zeolite-based nanopore sensing strategy that leverages the uniform nanopore channels and tunable adsorption properties of zeolites for achieving high selectivity in multi-analyte systems. Using bisphenol AF (BPAF) and bisphenol S (BPS)—two electrochemically overlapping phenolic pollutants with extreme similar structure—as model targets, we engineered and studied four zeolites: hydrophilic Hβ, surface-hydrophobic OS-Hβ (prepared by organosilane modification of Hβ), and two hydrophilic Y-type zeolites with contrasting Si/Al ratios (HY‑686 and NaY‑5). Notably, these materials exhibited distinct nanopore adsorption preferences: Hβ selectively adsorbed BPS, whereas OS-Hβ favored BPAF only; HY‑686 adsorbed both bisphenols, while NaY‑5 showed negligible uptake. Mechanistic studies revealed that for Beta-type zeolites with similar nanopore sizes, surface hydrophilicity/hydrophobicity governs selectivity, whereas for hydrophilic Y-type zeolites, nanopore size plays the decisive role. Building on this principle, we developed an innovative electrochemical nanopore sensing platform that integrates selective molecular absorption, in situ electrocatalysis, and interference-free detection, enabling accurate discrimination and quantification of BPAF and BPS in complex samples. This work not only resolves a persistent sensing challenge for structurally analogous analytes but also establishes a generalizable molecular‑sieving nanopore sensing principle for selective adsorption, electrocatalysis, and sensing applications.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139619"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146135327","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}

{"title":"Photoacoustic multi-gas sensor using mode division multiplexing","authors":"Mu Liang ,&nbsp;Mingqi Jiao ,&nbsp;Qing Yang ,&nbsp;Mingyang Feng ,&nbsp;Pengbo Chen ,&nbsp;Yang Gao ,&nbsp;Ya Gao ,&nbsp;Yingying Qiao ,&nbsp;Lei Li ,&nbsp;Chongxin Shan","doi":"10.1016/j.snb.2026.139583","DOIUrl":"10.1016/j.snb.2026.139583","url":null,"abstract":"<div><div>The multi-gas detection technology based on photoacoustic spectroscopy (PAS) has significant application value in fields such as power equipment, environmental protection, and medical diagnosis. It mainly relies on time-division multiplexing (TDM) and frequency-division multiplexing (FDM) technologies, but both have inherent technical limitations. TDM requires sequentially performing gas detection, resulting in a detection cycle that grows proportionally with the number of gas species, thus rendering it unsuitable for rapid multi-gas detection scenarios; FDM faces the contradictory between multi-frequency requirements and the uniqueness of the optimal resonant frequency, along with the drawback that deploying multiple lock-in amplifiers increases equipment costs and elevates system integration complexity. Therefore, we propose a mode-division multiplexing (MDM) method, which enables simultaneous and same-frequency measurements of multiple gases. By assigning differentiated scanning periods to different gases, the method encodes gas-specific width modes into mixed signals and achieves separation through a custom-designed signal separation framework. The system demonstrated linear fitting (R²) of 0.998 and 0.997 for CO and H₂S detection, with minimum detection limits reaching 75 ppb and 139 ppb. This method is applicable to all absorption spectroscopy-based multi-gas detection techniques employing wavelength modulation spectroscopy (WMS), offering a novel approach for multi-gas detection schemes.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139583"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186686","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}

{"title":"Electrochemical aptasensor for trimethoprim detection based on Pd@Ir bimetallic nanoparticles coupled with hybrid chain reaction","authors":"Man Ding ,&nbsp;Hong Xu ,&nbsp;Mengxia Duan ,&nbsp;Meihua Dong ,&nbsp;Kuaile Wu ,&nbsp;Shijia Wu ,&nbsp;Changqing Zhu ,&nbsp;Nuo Duan","doi":"10.1016/j.snb.2026.139575","DOIUrl":"10.1016/j.snb.2026.139575","url":null,"abstract":"<div><div>Trimethoprim (TMP), a widely used veterinary antibacterial, accumulates in animal-derived foods and poses health risks like bacterial resistance and bone marrow hematopoietic suppression. Herein, an ultrasensitive electrochemical aptasensor was developed by integrating molecular docking-optimized TMP-specific aptamers, Pd@Ir bimetallic nanoparticles (Pd@Ir NPs) for signal enhancement, and hybrid chain reaction (HCR) for signal amplification. First, a high-affinity TMP-specific aptamer TMP-1 was screened via Capture-SELEX. Through molecular docking to identify core binding sites and truncate redundant sequences, TMP-1 was optimized into the 56 nt TMP-1C with enhanced affinity (The Kd was determined to be 41.6 nM by SGI assays). Pd@Ir NPs with excellent conductivity and electrocatalytic activity were coupled to hairpin H2 to form Pd@Ir NPs@H2 probes. For sensor construction, thiol-modified cDNA-TMP-1C duplexes were immobilized on gold electrodes, the binding between TMP and aptamer induced the duplex de-hybridization, and the exposed cDNA opened H1 and triggered HCR, thereby achieving Pd@Ir NPs enrichment and signal amplification. This method exhibits an ultra-low limit of detection (LOD) of 0.02 ng/mL. The spiked recovery experiments on pork samples show that the recovery rate of TMP ranges from 92.00 % to 93.99 % with a relative standard deviation (RSD) of 3.34 %–3.89 %, confirming its accuracy in practical samples. This sensor provides an efficient, high-performance tool for TMP residue detection in food safety monitoring.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139575"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146089618","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}

{"title":"MoS2/CdS quantum dot heterojunction-based photoelectrochemical sensors for detecting persistent organic pollutants PCB28 in atmospheric precipitation","authors":"Yeqing Liu ,&nbsp;Hailin Zheng ,&nbsp;Heng Liu ,&nbsp;Chengyi Xiong ,&nbsp;Yao Xiao ,&nbsp;Miao-Miao Chen ,&nbsp;Shengfu Wang ,&nbsp;Xiuhua Zhang","doi":"10.1016/j.snb.2026.139593","DOIUrl":"10.1016/j.snb.2026.139593","url":null,"abstract":"<div><div>Polychlorinated biphenyls (PCBs) have drawn widespread international attention as persistent carcinogens posing significant environmental hazards. There has been an urgent need to develop rapid, sensitive, and portable methods to support environmental monitoring and pollution control. This work developed a photoelectrochemical (PEC) sensor based on molybdenum disulfide (MoS₂) nanosheets/CdS quantum dots (QDs) heterojunction for sensitive PCB28 detection in atmospheric precipitation. MoS₂ nanosheets served as both anchored platforms and protective layers to stabilize CdS QDs and prevented them from photocorrosion. The clean interface of 2D/0D MoS₂/CdS QDs heterojunctions could help to hinder photogenerated carrier recombination effectively, which then enabled electron-hole pairs to be significantly separated and thereby comprehensively improved sensor performances. The introduction of molecularly imprinted polymers (MIPs) with cavities specifically recognizing PCB28 enabled highly selective detection of the target compound. The sensor demonstrated good performance with a detection limit of 4.04 fg/mL. In practical atmospheric precipitation detection, results from this method were in good agreement with gas chromatography measurements. Furthermore, the sensor with the advantages of portability, simple pretreatment, and low cost, provided a novel strategy for reliable detection of trace pollutants in complex ambience. It also demonstrated that multidimension synergistic effects offered by mixed-dimensional heterojunctions could further enhance optoelectronic sensor performances for environmental monitoring.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139593"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146129460","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}

{"title":"A session-lasting biostable and biocompatible hydrogel microneedle patch for nanozyme-mediated on-site and smartphone-based quantification of skin H₂O₂","authors":"Sihui Wang ,&nbsp;Feng Liu ,&nbsp;Meng Sun ,&nbsp;Hongchun Gu ,&nbsp;Lei Yang ,&nbsp;Xun Feng ,&nbsp;Yang Chen","doi":"10.1016/j.snb.2026.139621","DOIUrl":"10.1016/j.snb.2026.139621","url":null,"abstract":"<div><div>Hydrogen peroxide (H₂O₂) in skin tissue serves as a critical biomarker for oxidative stress and physiological status, yet its precise in situ monitoring remains challenging due to the lack of non-invasive, real-time sensing platforms. Herein, we presented a smartphone-assisted biosensing system based on a nanozyme-integrated hydrogel microneedle patch for on-site and quantitative detection of cutaneous H₂O₂. The sensing platform incorporated a palladium-embedded metal-organic framework (Pd-PCN) with enhanced peroxidase-like activity, which was co-immobilized with a chromogenic substrate in a polymeric composite hydrogel microneedle array. This composite matrix maintained structural integrity and biocompatibility during short-term skin application while providing an aqueous microenvironment favorable for nanozyme-catalyzed reactions. Upon insertion into the skin, H₂O₂ from interstitial fluid would diffuse into the microneedle and trigger a colorimetric reaction. The resulting color intensity could be quantitatively captured via smartphone-based RGB analysis. The system demonstrated a wide linear detection range (5–100 µM), a low detection limit (1.53 µM), high reproducibility (RSD &lt; 5 %), and negligible interference from common biological substances. Confocal imaging and mechanical testing further confirm the structural stability and skin-penetration capability of the microneedle under operational conditions. This work established a reliable, minimally invasive, and user-friendly platform for continuous monitoring of oxidative biomarkers in skin, paving the way for personalized dermatological care and point-of-care diagnostics.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"454 ","pages":"Article 139621"},"PeriodicalIF":3.7,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146129714","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}