Analytica Chimica Acta最新文献

{"title":"Nanozyme fabrication based on magnetic COFs and gold nanorods and its SERS detection of zearalenone","authors":"Xiaoyuan Ma ,&nbsp;Xi Ma ,&nbsp;Muxi Zhang ,&nbsp;Jinchi Han ,&nbsp;Zhouping Wang","doi":"10.1016/j.aca.2026.345229","DOIUrl":"10.1016/j.aca.2026.345229","url":null,"abstract":"<div><h3>Background</h3><div>As one of the most common mycotoxins, Zearalenone (ZEN) not only contaminates cereal crops but also exists in processed grain products for its chemical stability. After entering human body through the food chain, ZEN exhibits remarkable bioaccumulation properties, which poses varying degrees of harmful effects to human health. The traditional chromatography instrumental methods require expensive equipment and complex experimental procedures. The aim of this manuscript is to develop a facile and accurate method for ZEN detection in food samples.</div></div><div><h3>Results</h3><div>Here, a SERS platform was developed for ZEN detection using COF and noble metal nanomaterial with nitroreductase (NTR)-like activity. First, magnetic COF loaded with gold nanoparticles (MCOF-Au) were synthesized as SERS enhancement substrates with partial NTR activity. Simultaneously, palladium-loaded dumbbell-shaped gold nanorods (AuNR/Pd) were prepared and served as the primary NTR in the 4-NTP/NaBH₄ system, significantly enhancing both catalytic activity and SERS signal. After nucleic acid functionalization, the two components assembled. The addition of ZEN regulated the assemble of AuNR/Pd on MCOF-Au. Following magnetic separation, the catalytic and SERS activities changed in the precipitate. Using the Raman peak of the output product 4-ATP at 390 cm⁻¹ as the quantitative marker, the method showed a linear range in 0.001 μg/kg-1000 μg/kg. The LOD was calculated as 1.88 × 10⁻⁴ μg/kg, and spiked recoveries in wheat flour and corn ranged from 88.91% to 115.78%, demonstrating high sensitivity and reliability for real-sample detection.</div></div><div><h3>Significance</h3><div>This aptasensor integrates the high sensitivity of Raman signals with the selectivity of aptamers, providing a robust and efficient tool for accurate ZEN detection in food. COF based nanocomposites are proved to have remarkable NTR activity and the catalytic product 4-ATP exhibits prominent Raman signal, making it suitable for quantitative detection. This design offers a versatile platform for food safety monitoring and public health protection.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1395 ","pages":"Article 345229"},"PeriodicalIF":6.0,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146153507","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An improved ion-exchange-to-silver-salt procedure for δ18O measurement of nitrate in natural samples","authors":"Bo Wang ,&nbsp;Chao Li ,&nbsp;Ying Wang ,&nbsp;Linbao Chen ,&nbsp;Yuting Wang ,&nbsp;Ran Ma ,&nbsp;Zhengyu Zhu ,&nbsp;Youping Zhou","doi":"10.1016/j.aca.2026.345228","DOIUrl":"10.1016/j.aca.2026.345228","url":null,"abstract":"<div><h3>Background</h3><div>The oxygen isotope composition (δ¹⁸O) of natural nitrate is a proven effective indicator of its sources and the (bio)geochemical processes that it has experienced. Removing interfering species (in particular oxyanions such as SO₄²⁻, PO₄³⁻, HPO₄²⁻ and H₂PO₄⁻) from natural samples with the currently established <strong>ion-exchange-to-silver-nitrate (IE2AgN)</strong> for reliable δ¹⁸O measurement with high temperature conversion-isotope ratio mass spectrometry (HTC-IRMS) involves a lengthy 5-step procedure. A less tedious and lower-cost <strong>IE2AgN</strong> procedure is highly desirable for high throughput analysis.</div></div><div><h3>Results</h3><div>We report an improved ion-exchange procedure based on the vast difference in solubilities in <em>n</em>-butyronitrile between AgNO₃ and interfering inorganic oxyanions. Nitrate was isolated from interfering inorganic oxyanions (and organic matter) as its silver salt following a 3-step procedure (anion-exchange, neutralization with Ag₂O and selective dissolution of AgNO₃ in <em>n</em>-butyronitrile). The δ¹⁸O of the purified nitrate was then analyzed by HTC-IRMS. A comparative δ¹⁸O analysis of the certified international nitrate O isotope standards before and after processing through our new 3-step and the current 5-step procedures showed them to yield comparably accurate and precise determinations with minimal isotope fractionation. The time required was more than halved (from 3-5 days to 1-2 days) as was the amount of expensive Ag₂O.</div></div><div><h3>Significance</h3><div>The simplified <strong>IE2AgN</strong> procedure will prove useful for high throughput and lower cost extraction of nitrate from natural samples for oxygen (and nitrogen) isotope analysis.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1395 ","pages":"Article 345228"},"PeriodicalIF":6.0,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146160609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microscale native size exclusion chromatography high resolution mass spectrometry for the determination of the chelator-to-antibody ratio of immunoconjugates","authors":"Annika A.M. van der Zon ,&nbsp;Bram Weijers ,&nbsp;Danielle J. Vugts ,&nbsp;Andrea F.G. Gargano","doi":"10.1016/j.aca.2026.345214","DOIUrl":"10.1016/j.aca.2026.345214","url":null,"abstract":"<div><h3>Background</h3><div>Positron emission tomography (PET) using radiolabeled antibodies (radioimmunoconjugates) is a powerful imaging technique to track the distribution of therapeutic antibodies. Accurate determination of the average number of chelators per antibody (CAR) is essential for (radio)immunoconjugate characterization, which is important for maximizing tumor uptake and image quality. Determination of the CAR is considered a critical quality attribute. Radiometric titration, although widely used, is labor-intensive, material- and time-consuming, and requires approximately half a day per sample. To overcome this analytical bottleneck, we developed a microscale size exclusion chromatography – mass spectrometry (SEC-MS) analysis.</div></div><div><h3>Results</h3><div>By applying microscale flow, high concentrations of volatile salts, up to 1000 mM ammonium acetate, could be used to minimize secondary interactions. Moreover, high isCID energy of 140 eV was applied to reduce adduct formation and enhance the MS sensitivity. The method was optimized using model radioimmunoconjugates based on intact trastuzumab, with a particular focus on the impact of buffer concentration on both chromatographic effects and CAR determination. A final buffer concentration of 600 mM ammonium acetate was selected. The method was compared with radionuclide titration for analysis of the same immunoconjugate model and yielded similar results. Finally, we demonstrated the broad applicability of the method by testing diverse immunoconjugates (<em>e.g.</em>, ipilimumab, rituximab), including cysteine- and lysine-linked chelators (<em>e.g.</em>, DFO, DOTA, RESCA), as well as other smaller protein models, such as nanobodies.</div></div><div><h3>Significance</h3><div>The optimized microflow native SEC-MS method, with a rapid 20-min run time, provides comprehensive characterization, including determination of the average CAR, dispersity index, glycosylation profile, and mAb impurities. Crucially, this native approach is applicable to all tested immunoconjugates, including chemically sensitive species such as those with maleimide and thiourea linkages, which often challenge denaturing methods like RPLC-MS. This establishes SEC-MS as a broadly applicable alternative to radiometric titration for the comprehensive characterization of immunoconjugates.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1395 ","pages":"Article 345214"},"PeriodicalIF":6.0,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146135286","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measuring absolute gas amounts with gas chromatography by using a novel setup for pressure based gas control","authors":"Andreas Hofmann,&nbsp;Ingo Reuter,&nbsp;Freya Müller,&nbsp;Anna Smith","doi":"10.1016/j.aca.2026.345217","DOIUrl":"10.1016/j.aca.2026.345217","url":null,"abstract":"<div><div>The characteristics of the gas itself, such as its volatility, compressibility, or weight, often complicate the process of feeding gas into a measuring system, such as a gas chromatograph. This is particularly relevant when quantifying individual gas components. While it is possible to inject gas with syringes, this method has several disadvantages, such as gas tightness and syringe and gas volume, especially for small gas quantities. Therefore, there is an urgent need for a simple, reliable, and improved method of gas injection into a measuring device. This study describes the development of a novel gas injection system that reliably and contaminant-free injects gas into gas chromatography (GC) instruments and other gas-related devices. The system consists of an injection unit, a vacuum system, and a loop assembly, and it connects directly to the corresponding device. Sample gas can then be introduced directly into the evacuated injection system and delivered to the measuring device. The system has been validated using a range of configurations and has undergone extensive testing. Additionally, two applications are presented to demonstrate the system's wide range of potential uses. Notably, the setup enables a contamination-free gas supply from battery pouch-bag cells. For this configuration, an adapter assembly was required for the pouch-bag cell and was integrated into the battery cell. Additionally, it is demonstrated how the setup can be used to determine the gas composition of a thermal decomposition reaction. This setup is a new, platform-independent option for introducing gas into a low-pressure environment and connecting it to devices without causing contamination. Reduced pressure enables multi-point calibration with a single reference or calibration gas mixture, which is pressure-dependent. Additionally, the integrated loop technology allows for the quantitative calculation of gas concentrations. Errors in calculating the amount of substance are less than 10–20%, even with flexible pouch cells.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1395 ","pages":"Article 345217"},"PeriodicalIF":6.0,"publicationDate":"2026-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146146661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation of ZIF-8 grafted magnetic solid-phase extraction sorbent for sensitive determination of four cannabinoids in urine and oral fluid","authors":"Hongyu Ning ,&nbsp;Yilei Fan ,&nbsp;Haodong Wang ,&nbsp;Huijun Liu ,&nbsp;Zhongping Huang ,&nbsp;Haixing Wang ,&nbsp;Xing Ke ,&nbsp;Yu Xu","doi":"10.1016/j.aca.2026.345194","DOIUrl":"10.1016/j.aca.2026.345194","url":null,"abstract":"<div><h3>Background</h3><div>The global increase in cannabis use has created a strong demand for reliable and efficient detection methods. Traditional urine-based assays are widely used and standardized, but suffer from complex hydrolysis requirements, long detection windows, and an inability to monitor recent use. In contrast, oral fluid testing enables non-invasive, real-time detection of parent cannabinoids, but is limited by low sample volume, matrix interference, and insufficient sensitivity in common rapid tests. It is clear that a sample preparation and detection approach is needed that is robust, highly sensitive, streamlined, and compatible with high-throughput confirmatory analysis such as LC-MS/MS.</div></div><div><h3>Results</h3><div>In this study, a magnetic solid-phase extraction (MSPE) method was developed using a novel magnetic metal–organic framework composite, Fe₃O₄@poly(GMA/DVB-ZIF-8), for the efficient extraction of four cannabinoids from urine and oral fluid. The sorbent uses multiple interactions—including hydrophobic, π–π, electrostatic, and Zn–O coordination—to achieve high analyte recovery (exceeding 85%). Coupled with UHPLC-MS/MS analysis, the method demonstrates wide linearity (0.05–25 ng/mL, r² &gt; 0.9945), low detection limits (as low as 0.017 ng/mL), and good repeatability (RSDs &lt;13.8%). Comparative evaluation with conventional liquid–liquid extraction showed minimal deviation (relative percent difference &lt;6.0%), confirming high trueness and reliability for cannabinoid monitoring in biological samples.</div></div><div><h3>Significance</h3><div>This MSPE approach provides a simple, efficient and high-throughput sample preparation method for reliable and rapid forensic analysis of cannabinoids in complex biological samples.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1394 ","pages":"Article 345194"},"PeriodicalIF":6.0,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146153231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative all-in-one high-performance thin-layer chromatography–planar start-zone enzyme assay applied for invertase activity","authors":"Isabel Müller,&nbsp;Viktoria H. Englert,&nbsp;Gertrud E. Morlock","doi":"10.1016/j.aca.2026.345213","DOIUrl":"10.1016/j.aca.2026.345213","url":null,"abstract":"<div><h3>Background</h3><div>Conventional methods for assessing enzyme activity often rely on <em>in vitro</em> assays with spectrophotometric detection; however, they lack accuracy for complex substrates. The recently introduced nanoGIT concept demonstrated the potential of on-surface enzyme assays performed directly in the start zone, followed by high-performance thin-layer chromatography (HPTLC) of the formed products on the same adsorbent surface. For the first time, the potential of this all-in-one HPTLC concept was investigated for the quantification of enzyme (invertase) activity using a complex substrate.</div></div><div><h3>Results</h3><div>Enzymatic hydrolysis of sucrose or egg biscuit extract was carried out in the start zone under identical conditions for all studied samples. On the same adsorbent surface, the hydrolysis products were separated, detected via densitometric fluorescence measurement, and quantified. Even with complex substrates, the integrated separation provided accurate, in-depth information on enzyme characteristics from the individual products formed and their respective intensities. The method was validated and proved to be accurate and reliable in the nanomolar range, outperforming current spectrophotometric <em>in vitro</em> assays that operate in the millimolar range. The assay in the start zone exhibited remarkable sensitivity, requiring a 12,500-fold lower substrate quantity while using equivalent enzyme amounts. Limitations and benefits were discussed.</div></div><div><h3>Significance</h3><div>For the first time, a validated quantitative all-in-one HPTLC–start-zone enzyme assay–FLD method was successfully demonstrated for the determination of the enzyme activity. It enabled the quantification of even minor amounts of individual enzyme reaction products, providing improved sensitivity and more accurate insights into enzyme characteristics. Low enzyme levels can be analysed, extending current analytical capabilities.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1394 ","pages":"Article 345213"},"PeriodicalIF":6.0,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146138739","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Standardized digital PCR assay validation using PCR-ValiPal, demonstrated in cross-platform quantification of bovine papilloma virus","authors":"David Gleerup ,&nbsp;Matthijs Vynck ,&nbsp;Lien Gysens ,&nbsp;Cindy De Baere ,&nbsp;Wim Trypsteen ,&nbsp;Jo Vandesompele ,&nbsp;Olivier Thas ,&nbsp;Ann Martens ,&nbsp;Maarten Haspeslagh ,&nbsp;Ward De Spiegelaere","doi":"10.1016/j.aca.2026.345210","DOIUrl":"10.1016/j.aca.2026.345210","url":null,"abstract":"<div><h3>Background</h3><div>Digital PCR (dPCR) enables precise and absolute quantification of nucleic acids by partitioning samples into thousands of reactions, improving reproducibility and reducing reliance on standard curves compared to qPCR. However, rigorous assay validation remains essential to ensure reliability, particularly for parameters such as limit of detection, limit of quantification, trueness, and linearity. Existing guidelines (e.g., MIQE, dMIQE, ISO 20395:2019) highlight these requirements, but implementation is laborious and inconsistent across laboratories. To address this, we developed PCR-ValiPal, a user-friendly web application that standardizes and streamlines dPCR assay validation and reporting.</div></div><div><h3>Results</h3><div>PCR-ValiPal calculates the full range of analytical parameters required for ISO-compliant assay validation, including limit of blank, limit of detection, limit of quantification, precision, trueness, and linearity. While broadly applicable to any nucleic acid target, we demonstrate its use with a three-color PCR assay for bovine papillomavirus (BPV), a clinically relevant representative DNA assay, types 1 and 2, benchmarked across four platforms: Naica (droplet dPCR), QIAcuity (microwell dPCR), LOAA (real-time dPCR), and CFX96 (qPCR). Cross-platform comparisons revealed Naica and QIAcuity achieved low LOB and LOQ values with minimal bias, while LOAA exhibited stable but negative bias. qPCR performed best for BPV-2 sensitivity but was less reliable for BPV-1 at low concentrations. These results illustrate both the value of platform-specific optimization and the utility of PCR-ValiPal in providing transparent, standardized validation outputs.</div></div><div><h3>Significance</h3><div>PCR-ValiPal supports transparent, reproducible, and ISO-aligned validation of PCR-based assays, lowering barriers for both expert and non-expert users. By centralizing statistical analyses in a single tool, it enables reliable comparison across platforms and targets, facilitating adoption in research, diagnostics, and regulatory contexts. This work underscores the importance of standardized validation for ensuring confidence in nucleic acid quantification.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1394 ","pages":"Article 345210"},"PeriodicalIF":6.0,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146135312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Two-dimensional AEX – IP-RPLC: New insights on mRNA integrity and encapsulation efficiency of mRNA-lipid nanoparticle formulations","authors":"Megane K. Aebischer ,&nbsp;Athanasios Tsalmpouris ,&nbsp;Serge Rudaz ,&nbsp;Camille Malburet ,&nbsp;Jean-François Cotte ,&nbsp;Davy Guillarme ,&nbsp;Jonathan Maurer","doi":"10.1016/j.aca.2026.345215","DOIUrl":"10.1016/j.aca.2026.345215","url":null,"abstract":"<div><h3>Background</h3><div>Therapeutics and vaccines involving mRNA have shown significant progress over the last five years. These lipid nanoparticle-based formulations introduce substantial analytical complexity, as multiple Quality Attributes (QAs) must be monitored to ensure product efficacy, stability, and safety. Encapsulation efficiency (EE) and mRNA integrity are particularly critical, yet current analytical approaches often require separate assays, challenging sample handling, and limited selectivity toward free versus encapsulated species. Therefore, new chromatographic methods capable of resolving these species and supporting multi-payload formulations remain a major unmet need.</div></div><div><h3>Results</h3><div>To rapidly obtain multiple QAs for mRNA-LNP formulations, we present an optimized two-dimensional liquid chromatography (2D-LC) workflow combining anion-exchange chromatography (AEX) in the first dimension (¹D) and ion-pair reversed-phase liquid chromatography (IP-RPLC) in the second dimension (²D). The ¹D-AEX evaluated encapsulation efficiency of mRNA within lipid nanoparticles based on the mRNA ratio of intact and disrupted drug products, while ²D-IP-RPLC assessed integrity profiles and mRNA-lipid adducts. Attention was paid to the ²D optimization to eliminate solvent incompatibilities and ensure efficient transfer between dimensions.</div><div>This approach enables simultaneous determination of EE, mRNA integrity, mRNA-lipid adducts, and transcript ratios in multi-payload mRNA-LNP formulations. It also provides chromatographic assessment of free mRNA integrity within formulations. This method furthermore enables the characterization of additional species and confirms the presence of surface-associated mRNA. The workflow demonstrates good selectivity and applicability to both mono- and multi-payload mRNA-LNP products.</div></div><div><h3>Significance</h3><div>Overall, the developed 2D-LC platform is a powerful analytical tool for comprehensive mRNA-LNP characterization. By enabling simultaneous assessment of several critical QAs, including EE, integrity, transcript ratios, and mRNA-lipid adducts, it streamlines analytical workflows and reduces reliance on multiple independent assays. This approach provides mechanistic insight into LNP structure, including detection of surface-associated RNA species, and establishes an innovative tool to support formulation development, process optimization, drug products release, and stability studies for next-generation mRNA vaccines and therapeutics.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1394 ","pages":"Article 345215"},"PeriodicalIF":6.0,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146135285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SPARC: A programmable molecular diagnostic platform based on a signal-triggered, self-supplied crRNA and tiered PER-transcription-CRISPR cascade for early detection of hepatocellular carcinoma","authors":"Xinying Chang ,&nbsp;Cong Han ,&nbsp;Haishuo Ji ,&nbsp;Zhe Zeng ,&nbsp;Jingyi Yang ,&nbsp;Qirui Liu ,&nbsp;Chao Jia ,&nbsp;Lili Zhao ,&nbsp;Chunlei Zhou ,&nbsp;Shujia Chen ,&nbsp;Wolfgang Knoll ,&nbsp;Jia Li ,&nbsp;Zhenglu Wang ,&nbsp;Liyun Zhang","doi":"10.1016/j.aca.2026.345209","DOIUrl":"10.1016/j.aca.2026.345209","url":null,"abstract":"<div><h3>Background</h3><div>Accurate quantification of microRNAs (miRNAs) is essential for early cancer detection, yet remains challenging due to their short length, low abundance, and high sequence similarity. Existing assays often struggle to achieve sufficient sensitivity, specificity, and robustness for reliable clinical deployment.</div></div><div><h3>Results</h3><div>We introduce <strong>SPARC</strong>, a programmable molecular diagnostic platform that integrates a signal-triggered primer exchange reaction, self-supplied crRNA generation, and a tiered PER–transcription–CRISPR/Cas12a amplification cascade. Using miRNA-21 as a model, SPARC achieves an ultralow detection limit of 1.22 fM and a broad quantitative range from 1 fM to 100 nM. The system exhibits high specificity, strong analytical stability, and modular adaptability to diverse targets, including miRNA-122. Notably, the dual-directional profiling of oncogenic and tumor-suppressive miRNAs enhances diagnostic resolution. When applied to HCC cell lines and clinical tissues, SPARC accurately distinguished malignant from normal samples and showed excellent agreement with qRT-PCR measurements and histopathological assessments.</div></div><div><h3>Significance</h3><div>This streamlined and self-amplifying cascade system provides a scalable, robust, and clinically compatible platform for ultrasensitive miRNA detection. SPARC holds strong potential for early hepatocellular carcinoma screening, molecular subtyping, and broader precision oncology applications.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1394 ","pages":"Article 345209"},"PeriodicalIF":6.0,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146146203","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"COF-Zincon dual signal amplification: A sensitive real-time electrochemical sensor for Zn2+ detection towards anxiety disorder diagnosis","authors":"Honglong Zou ,&nbsp;Yonggui Song ,&nbsp;Jiaqi Shao ,&nbsp;Bin Lai ,&nbsp;Qinghui Fu ,&nbsp;Zhifu Ai ,&nbsp;Yali Liu ,&nbsp;Yuhui Ping ,&nbsp;Dan Su ,&nbsp;Youhui Zhang ,&nbsp;Huihui Liang","doi":"10.1016/j.aca.2026.345220","DOIUrl":"10.1016/j.aca.2026.345220","url":null,"abstract":"<div><h3>Background</h3><div>In recent years, abnormal total zinc levels in serum have emerged as a robust indicator of anxiety disorder. However, measuring total zinc level requires sophisticated instrumentation and specialized personnel. Therefore, if the specific association between Zn²⁺ in serum and anxiety disorder can be elucidated, it is promising to develop rapid and convenient diagnostic methods for anxiety disorder. In the field of Zn²⁺ detection, Electrochemical detection has been investigated as a means to quantify Zn²⁺ with precision, rapidity and cost-effectiveness. Nevertheless, most current electrochemical systems lack specificity.</div></div><div><h3>Results</h3><div>In this study, the relationship between anxiety disorder and serum Zn²⁺ level was first elucidated, with research finding indicating that anxiety in mice correlated with a marked decline in serum Zn²⁺ level. Subsequently, a sensitive and specific electrochemical sensor was developed to detect Zn²⁺ with outstanding detection performance for the diagnosis of anxiety disorder. In this sensor, covalent organic framework material (COF_Tp-Th) was utilized to load a substantial amount of gold nanoparticles (AuNPs) via Au–N bonds to obtain COF_Tp-Th-AuNPs material. AuNPs can enhance electrode catalysis and conductivity and served as a platform for subsequent material integration. Furthermore, a large quantity of Zincon reagent for specific recognition and detection of Zn²⁺ was loaded onto the AuNPs through Au–S and Au–N bonds to improve electrode specificity, resulting in the construction of the target electrode modified material of COF_Tp-Th-AuNPs-Zincon.</div></div><div><h3>Significance</h3><div>Long-range ordered COF_Tp-Th can adsorb Zn²⁺ through its rich tetradentate coordination ONNO chelation sites formed by Tp and Th, representing the primary signal amplification. Simultaneously, the abundant Zincon in COF_Tp-Th-AuNPs-Zincon material with high affinity for the specific recognition and detection of Zn²⁺ contributed to secondary signal amplification. This approach leads to a significant improvement in the detection performance of Zn²⁺ and holds promise for providing robust support for the diagnosis and monitoring of anxiety disorder.</div></div>","PeriodicalId":240,"journal":{"name":"Analytica Chimica Acta","volume":"1394 ","pages":"Article 345220"},"PeriodicalIF":6.0,"publicationDate":"2026-04-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146146662","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}