Sensors and Actuators B: Chemical最新文献

{"title":"Electron density modulation based NIR probe for rapid and specific imaging of vicinal dithiol proteins in rheumatoid arthritis","authors":"Liangying Mi ,&nbsp;Tao Ma ,&nbsp;Fei Han ,&nbsp;Ruipeng Shen ,&nbsp;Mengzhao Zhang ,&nbsp;Jia Lu ,&nbsp;Suling Wan ,&nbsp;Dongzhu Duan ,&nbsp;Baoxin Zhang","doi":"10.1016/j.snb.2026.139662","DOIUrl":"10.1016/j.snb.2026.139662","url":null,"abstract":"<div><div>Vicinal dithiol proteins (VDPs) represent a distinct class of thiol-based pervasive proteins with a key part of maintaining the balance of oxidants and antioxidants; nevertheless, their involvement in various diseases makes them essential health indicators. Consequently, the development of advanced tools for the sensitive and selective detection of VDPs is imperative. As part of our ongoing research, we recently reported a couple of VDP-responsive fluorescent probes employing N-benzylacrylamide as a selective trigger unit. However, the overall efficiency of these probes could be hampered due to their short emission wavelengths, inadequate resistance to glutathione (GSH) interference, and long reaction times (&gt;20 min). To overcome such challenges, a series of fluorescent probes were engineered by systematically modulating the electronic properties of the N-benzylacrylamide recognition unit through the introduction of different substituents at the <em>para</em> position of the phenyl ring and incorporating a hemi-cyanine-based fluorophore scaffold. The preliminary evaluations revealed that the probe <strong>HCY-CF</strong>_{<strong>3</strong>} showed excellent specificity and sensitivity towards VDPs. Leveraging its superior characteristics, <strong>HCY-CF</strong>_{<strong>3</strong>} was successfully used to visualize and monitor dynamic alterations in VDP levels both in living cells and in the rheumatoid arthritis (RA) mouse model. Collectively, the results present a practical tool for diagnosing diseases associated with aberrant VDP expression.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139662"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147386184","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":"Nanoporous copper microdisc arrays for non-enzymatic detection of glucose in aqueous and saliva solutions","authors":"Ehren M. Dixon,&nbsp;Lorraine C. Nagle,&nbsp;James F. Rohan","doi":"10.1016/j.snb.2026.139585","DOIUrl":"10.1016/j.snb.2026.139585","url":null,"abstract":"<div><div>To address the stability and cost limitations of enzymatic glucose sensors, this work details the use of nanoporous copper (NPC) modified microdisc array (MDA) sensors for non-enzymatic glucose detection, with a focus on bovine health monitoring. Electrochemical analysis in 0.1 M NaOH, using cyclic voltammetry (CV) and chronoamperometry (CA), demonstrated excellent sensor performance. The device demonstrated a wide linear detection range (0.01 – 4.0 mM, R²&gt;0.99) and a 4 µM limit of detection (LOD). It achieved high sensitivities of 14.87 and 9.87 µA µM⁻¹ cm⁻² across its low-concentration and full linear detection ranges, respectively. The sensor showed high selectivity, with minimal interference from common analytes in saliva and blood, and ageing studies revealed stable performance for up to 56 days when stored in acetone. Successful validation in artificial saliva confirmed the sensor's applicability for direct biofluid analysis. These findings establish NPC-modified MDAs as a robust, cost-effective, and promising platform for glucose monitoring in complex biofluids, particularly for veterinary diagnostics and agri-tech applications.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139585"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146129715","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 highly sensitive and temperature-compensated near-infrared plasmonic biosensing platform for label-free isothermal nucleic-acid amplification","authors":"Shiqi Hu ,&nbsp;Lingling Zhang ,&nbsp;Weicheng Shi ,&nbsp;Tingting Liu ,&nbsp;Yuanyuan Han ,&nbsp;Qiao Zhao ,&nbsp;Yaofei Chen ,&nbsp;Gui-Shi Liu ,&nbsp;Lei Chen ,&nbsp;Zhe Chen ,&nbsp;Wei Xiao ,&nbsp;Donglin Cao ,&nbsp;Yunhan Luo","doi":"10.1016/j.snb.2026.139614","DOIUrl":"10.1016/j.snb.2026.139614","url":null,"abstract":"<div><div>Isothermal amplification technology (IAT), an enzymatic nucleic acid amplification technique conducted at a constant temperature, has garnered significant attention due to its simplicity, rapidness, and reduced equipment requirements in molecular biology. However, the current quantitative analysis of IAT results predominantly relies on dye-labeling methods, which not only complicate the operation but also increase the requirements for instrumentation. To address the pressing needs for highly sensitive, label-free, and constant-temperature detection in IAT, we propose and validate a dual resonance surface plasmon resonance (SPR) sensing platform with temperature-compensated capability. Through a bridge wedge prism (BWP) design featuring a small incident angle and dual resonance, this platform forms two near-infrared sensing regions achieving high sensitivity at 13500.00 and 46766.67 nm/RIU, respectively. An integrated thermoelectric cooler is also employed to precisely regulate the biosensing platform's temperature, meeting the constant-temperature requirements of 37–55°C for IAT. To address temperature drift in high-sensitivity applications, a matrix effectively is implemented for temperature compensation. The utilization of this platform for the quantitative analysis of synthetic human immunodeficiency virus (HIV) single-stranded deoxyribonucleic acid (ssDNA) via recombinase polymerase amplification (RPA) facilitated the detection across diverse amplification durations and sample concentrations. Furthermore, nucleic acid probe binding enables evaluation of amplicon specificity, providing a highly promising platform for advancing label-free nucleic acid amplification and real-time detection technologies.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139614"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146146205","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":"SPECTRA-based detection of drug-induced hepatotoxicity through extracellular vesicle analysis","authors":"Ugur Parlatan ,&nbsp;Luke Boudreau ,&nbsp;Hulya Torun ,&nbsp;Letao Fan ,&nbsp;Ugur Aygun ,&nbsp;Ayse Aslihan Gokaltun ,&nbsp;Demir Akin ,&nbsp;O. Berk Usta ,&nbsp;Utkan Demirci","doi":"10.1016/j.snb.2026.139520","DOIUrl":"10.1016/j.snb.2026.139520","url":null,"abstract":"<div><div>Extracellular vesicles (EV) are becoming crucial targets in liquid biopsy, diagnostics, and therapeutic applications, yet their nanoscale characterization remains challenging. In this context, the detection of drug-induced liver injury, <em>i.e.,</em> hepatotoxicity, through EV molecular content remains unexplored. To this end, we present the SPECTRA - <u>S</u>urface <u>P</u>lasmonic <u>E</u>nhancement with <u>C</u>ombined <u>T</u>ransformative <u>RA</u>man and Interferometric Microscopy approach, which provides rapid, label-free EV content analysis under 30 min and requires only 1.3 microliters of EV sample. Using hepatic cultures as a model, our platform captures distinct and reproducible EV molecular changes in response to acetaminophen-induced hepatotoxicity. Across independent culture sets, a Gaussian Process Regression model predicted Acetaminophen (APAP) dose with median absolute error of 1.50 mM and minimal bias (Bland–Altman bias ∼0.03 mM); cross-validated RMSE was 3.145 mM. These findings establish EVs as dynamic reporters of cellular drug responses and demonstrate use of SPECTRA for EV detection of hepatotoxicity.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139520"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146014733","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":"Photocurrent-polarity-switching photoelectrochemical and electrochemical dual-mode immunosensor for staphylococcal enterotoxin B assay based on multifunctional COF@hemin probe","authors":"Guizhen Luo ,&nbsp;Ke Xiao ,&nbsp;Cuicui Du ,&nbsp;Xiaohua Zhang ,&nbsp;Jinhua Chen","doi":"10.1016/j.snb.2026.139636","DOIUrl":"10.1016/j.snb.2026.139636","url":null,"abstract":"<div><div>Staphylococcus enterotoxin B (SEB), a superantigen secreted by Staphylococcus aureus, is a significant pathogenic factor responsible for foodborne infections and food poisoning. Therefore, the sensitive detection of SEB is crucial and remains challenging. Herein, a dual-mode immunosensor that integrated photoelectrochemical (PEC) and electrochemical (EC) techniques was developed for the highly sensitive analysis of SEB, utilizing multifunctional hemin-loaded covalent organic frameworks (COF@hemin) as a signaling probe capable of both switching photocurrent polarity and generating electrochemical signals. The COF@hemin composite was synthesized by functionalization of COF-V with sulfhydryl groups, enabling efficient immobilization of hemin via a sulfhydryl-ene click reaction. After that, SEB antibody (Ab2) was connected to the COF@hemin composite through amide bonding to form Ab2-COF@hemin. Based on the SEB-mediated specific immune sandwich reaction, Ab2-COF@hemin was captured by a photoactive zinc-based metal-organic framework (Zn-MOF)-modified ITO electrode which was pre-immobilized with primary antibody (Ab1). The introduced COF@hemin not only switched the anodic photocurrent of Zn-MOF/ITO electrode to cathodic photocurrent, but also generated high electrochemical response due to the redox ability of hemin. Thus, the constructed PEC-EC dual-mode sensor enabled sensitive detection of SEB, demonstrating a linear range from 0.1 pg mL⁻¹ to 10 ng mL⁻¹ and a detection limit of 0.03 pg mL⁻¹ in PEC mode, and a linear range from 1 pg mL⁻¹ to 5 ng mL⁻¹ with a detection limit of 0.2 pg mL⁻¹ in EC mode. In addition, the proposed immunosensor demonstrated satisfactory performance in SEB detection in complex samples, indicating its potential applicability in food safety monitoring.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139636"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146139040","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 high-sensitivity aptamer-phage dual-recognition strategy for electrochemical detection of Salmonella typhimurium in poultry","authors":"Yihang Yang ,&nbsp;Xinyu Fang ,&nbsp;Cong Liu ,&nbsp;Shulei Zhang ,&nbsp;Zhiyu Yang ,&nbsp;Xu Jin ,&nbsp;Liling Hao ,&nbsp;Fei Xu","doi":"10.1016/j.snb.2026.139632","DOIUrl":"10.1016/j.snb.2026.139632","url":null,"abstract":"<div><div><em>Salmonella typhimurium</em> (<em>S. typhimurium</em>) is a prominent foodborne pathogen frequently detected in poultry and egg products, posing persistent challenges to food safety. Herein, we present a dual-recognition electrochemical biosensor that integrates aptamers and bacteriophages (phages) for highly sensitive detection of <em>S. typhimurium</em>. Tetrahedral DNA nanostructures (TDNs) incorporating <em>S. typhimurium</em> aptamers were employed to spatially assemble aptamers on the electrode surface, thereby improving capture efficiency. Meanwhile, phages were directionally immobilized on calcined zeolitic imidazolate framework (QZIF-67) nanostructures loaded with methylene blue (MB) via electrostatic adsorption, serving as both biorecognition and signal amplification elements. Upon target recognition, an “aptamer-bacterium-phage” sandwich complex was formed, which brought MB molecules closer to the electrode and significantly enhanced the electrochemical response. The biosensor achieved an ultralow detection limit of 2.6 CFU/mL and demonstrated excellent recovery rates (90.09–108.70 %) in spiked chicken and egg samples, confirming its reliability and applicability. This work provides a practical and integrated approach for rapid and ultrasensitive bacteria detection in food safety monitoring.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139632"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146139043","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 rapid, sample-to-answer strategy for the multiplex detection of intact respiratory pathogens","authors":"Shijue Gao ,&nbsp;Liang Bai ,&nbsp;Yujie Xiang ,&nbsp;Hong Liu ,&nbsp;Zifan Yang ,&nbsp;Fengyu Tian ,&nbsp;Xiaoping Chen ,&nbsp;Xinxin Shen ,&nbsp;Xuejun Ma","doi":"10.1016/j.snb.2026.139658","DOIUrl":"10.1016/j.snb.2026.139658","url":null,"abstract":"<div><div>Respiratory pathogens have long represented a significant cause of global pandemics, highlighting the critical need for reliable tools to evaluate their infectivity. However, conventional nucleic acid- or antigen-based detection methods often fail to accurately reflect the actual infection risk posed by the intact pathogens present in clinical samples. To address this limitation, this study developed a detection strategy for six-plex intact respiratory pathogens in swabs, coupling a broad-spectrum capture and viability dye treatment with an automated microfluidic platform. Specifically, recombinant human mannan-binding lectin-functionalized magnetic beads (rhMBL-MBs) are used to capture intact pathogens, while improved propidium monoazide (PMAxx) prevents amplification of compromised ones. Following this pretreatment, the microfluidic platform automates the processes of nucleic acid extraction, recombinase aided amplification (RAA), fluorescence detection, and wireless data transmission. This sample-to-answer workflow delivers results within 45 min, achieving the lowest detection limits of 5 50 % tissue culture infectious dose per milliliter (TCID₅₀/mL) for intact pathogens. The clinical utility of this strategy was validated using 40 swabs collected at multiple time points post-diagnosis (confirmed by RT-qPCR/qPCR) and 10 healthy controls. Results showed a 100 % detection rate for samples collected 2–3 days post-diagnosis and 40 % for those collected 7–10 days post-diagnosis, demonstrating its effective differentiation of intact, potentially infectious pathogens in clinical specimens. With high specificity, rapid turnaround, and design flexibility, this approach shows strong potential for assessing transmission risks and informing evidence-based infection control strategies, including decisions on isolation duration.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139658"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146160616","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":"Highly sensitive and selective determination of nuclear matrix protein 22 based on an epitope imprinted electrochemical biosensor","authors":"Xia He ,&nbsp;Yuankun Zheng ,&nbsp;Yuting Zhang ,&nbsp;Jia He ,&nbsp;Mengting Li ,&nbsp;Jinqi Li ,&nbsp;Zhenping Liu ,&nbsp;Huikai Shao","doi":"10.1016/j.snb.2026.139623","DOIUrl":"10.1016/j.snb.2026.139623","url":null,"abstract":"<div><div>Nuclear matrix protein 22 (NMP22) is a well-recognized biomarker for bladder cancer; however, conventional detection methods often suffer from insufficient sensitivity, high-cost and time-consuming. In this work, a novel epitope molecularly imprinted polymer (EMIP)-based electrochemical biosensor was constructed for highly selective and sensitive determination of NMP22. The EMIP biosensor was fabricated by electro-polymerization with C-terminal dodecapeptide (GATPRAKGKAKH, named as epitope) of NMP22 as template and <em>o</em>-phenylenediamine (<em>o</em>-PD) as functional monomer on the gold electrode (AuE) which was previously self-assembled with thiolated graphene (G-SH) and gold nanoparticles (AuNPs). The use of G-SH and AuNPs can supply synergistic effects for enhancing detection sensitivity and epitope imprinting of C-terminal dodecapeptide of NMP22 can provide high selectivity for NMP22 detection. To obtain the superior sensitivity, several experimental parameters affecting the performance of the EMIP electrochemical sensor were investigated, including the molar ratio of template to functional monomer, electropolymerization cycle, elution time and incubation time. Under the optimal experiment, this EMIP electrochemical biosensor exhibited a good linear relationship for NMP22 in the concentration range from 0.1 pg mL⁻¹ to 1.0 μg mL⁻¹, with a limit of detection (LOD) of 0.077 pg mL⁻¹. Finally, the EMIP electrochemical biosensor was successfully used for the determination of NMP22 in human urine with the recovery rates ranging from 96.92 % to 100.88 %. Compared with conventional ELISA, the proposed EMIP biosensor displayed shorter detection time, improved reproducibility and comparable analytical reliability. These findings highlight that the developed EMIP biosensor holds strong potentials for early bladder cancer diagnosis and broader clinical applications.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139623"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146135283","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 DNA logic gate-regulated ECL biosensor for detecting cfDNA from multidrug-resistant Mycobacterium tuberculosis","authors":"Shihua Sun ,&nbsp;Wenyan Li ,&nbsp;Weiyao Zhong ,&nbsp;Fangyan Ji ,&nbsp;Peilin Wang ,&nbsp;Jingwei Shi ,&nbsp;Qiang Ma","doi":"10.1016/j.snb.2026.139655","DOIUrl":"10.1016/j.snb.2026.139655","url":null,"abstract":"<div><div>Multidrug-resistant tuberculosis (MDR-TB) is a form of tuberculosis caused by <em>Mycobacterium tuberculosis</em> strains that are resistant to at least rifampicin (RIF) and isoniazid (INH) simultaneously. The most common mutations causing RIF and INH resistance are rpoB531 and katG315, respectively. This study innovatively develops a DNA logic gate-regulated electrochemiluminescence–resonance energy transfer (ECL-RET) sensor to achieve specific identification of cell-free DNA (cfDNA) from drug-resistant <em>Mycobacterium tuberculosis</em>. Zn-metal organic framework (Zn-MOF) with excellent anodic ECL performance is prepared as the ECL emitter and energy donor. Meanwhile, Au NPs-MXene heterojunction is synthesized as the ECL-RET acceptor. In this DNA logic gate-regulated sensing system, two cfDNA strands with rpoB531 and katG315 mutations function as inputs for an AND logic gate, which further activates toehold-mediated strand displacement (TMSD) to release the connecting chain. As a result, the ECL-RET between Zn-MOF and Au NPs-MXene heterojunction is achieved. This DNA logic gate-regulated ECL sensor is used to detect rpoB531 and katG315 mutation cfDNA in urine samples successfully. The sensitive detection for rpoB531 and katG315 is achieved with a linear range of 10 fM to 100 nM and a limit of detection (LOD) of 0.9 fM. This strategy offers a novel method for the non-invasive and rapid diagnosis of MDR-TB.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"455 ","pages":"Article 139655"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146198838","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":"Enhanced Formaldehyde Gas Sensing of Ag-Doped NiFe2O4 Spinel Ferrites","authors":"Souha Gharbi ,&nbsp;Sirine. Gharbi ,&nbsp;Abd daim Jeidd ,&nbsp;Ahmadou Ly ,&nbsp;E. Dhahri ,&nbsp;R. Barillé ,&nbsp;M. Debliquy ,&nbsp;D. Lahem","doi":"10.1016/j.snb.2026.140178","DOIUrl":"10.1016/j.snb.2026.140178","url":null,"abstract":"<div><div>In this study, NiFe_1.9 Ag_0.1 O₄ spinel ferrite nanoparticles were successfully prepared using the sol-gel method, followed by successive annealing steps at 600 °C and 700 °C for 24<!--> <!-->h each. A key novelty of this work is the demonstration that silver incorporation significantly enhances gas-sensing performance toward low-concentration formaldehyde (HCHO) while strictly maintaining a single-phase cubic spinel structure (space group Fd<span><math><mover><mrow><mn>3</mn></mrow><mo>̅</mo></mover></math></span>m). Structural and morphological analyses via X-ray diffraction (XRD) confirmed high crystallinity, while TEM imaging revealed nearly spherical nanoparticles with an average diameter of 32<!--> <!-->nm. Energy-dispersive X-ray (EDX) mapping verified a homogeneous elemental distribution of Ni, Fe, Ag, and O throughout the spinel lattice. To evaluate gas-sensing capabilities, the synthesized powder was spray-deposited onto alumina substrates to form thick-film sensors. The optimized sensor exhibited a peak response of 1.7 toward 5 ppm HCHO at an operating temperature of 275 °C, achieving a notable detection limit of 0.5 ppm. Furthermore, the device demonstrated rapid kinetics with response and recovery times of 58<!--> <!-->s and 148<!--> <!-->s, respectively alongside excellent repeatability and robust humidity tolerance. These findings position Ag-doped NiFe₂O₄ as a highly promising sensing material for precise environmental monitoring of formaldehyde.</div></div>","PeriodicalId":425,"journal":{"name":"Sensors and Actuators B: Chemical","volume":"464 ","pages":"Article 140178"},"PeriodicalIF":3.7,"publicationDate":"2026-05-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147997729","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}