Analyst最新文献

{"title":"A CRISPR/Cas13a-based and hybridization chain reaction coupled evanescent wave biosensor for SARS-CoV-2 gene detection†","authors":"Yang Li, Yikan Zhao, Zhihao Yi and Shitong Han","doi":"10.1039/D4AN01584C","DOIUrl":"10.1039/D4AN01584C","url":null,"abstract":"<p >Timely and accurate diagnosis of RNA viruses, represented by the SARS-CoV-2, is the foundation for protecting people from health threats. Currently, direct detection of viral RNA genes remains the most accurate method. Herein, a rapid, ultrasensitive, and no heating equipment required CRISPR/Cas13a based evanescent wave fluorescence biosensing platform for quantitative detection of the SARS-CoV-2 gene is reported. The collateral effect of CRISPR/Cas13a for RNA is combined with a self-driven enzyme-free hybridization chain reaction (HCR) as a signal amplification step. When the initiator RNA strand is cleaved by Cas13a, the downstream signal amplification induced by HCR is blocked, and a multiple crRNA strategy is used to enhance the cleavage efficiency. The newly designed HCR assemblies are captured by the cDNA-modified optical fiber and generate a higher-intensity fluorescence signal induced by the evanescent field. The CRISPR/Cas13a-HCR evanescent wave fluorescence biosensing platform is capable of detection of SARS-CoV-2 with a LOD of 0.47 copies per μL and the detection time is within 35 min. The spike recovery tests in saliva and high specificity have demonstrated the potential of this method for point-of-care diagnosis. This method is also suitable for the detection of other RNA viruses, without the need to alter any design of the HCR component, and only the corresponding crRNA needs to be replaced.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 7","pages":" 1367-1376"},"PeriodicalIF":3.6,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506827","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measurement of fluid viscosity based on pressure-driven flow digital-printed microfluidics†","authors":"Yan Ge, Xingxing Huang, Baojian Zhang, Zhixiong Song, Xusheng Tang, Shuai Shao, Lujiale Guo, Peng Liang and Bei Li","doi":"10.1039/D4AN01550A","DOIUrl":"10.1039/D4AN01550A","url":null,"abstract":"<p >Viscosity is an important characteristic of fluids. Microfluidics has shown significant advantages in the viscosity measurement of biopharmaceuticals, especially in meeting the needs of low sample volumes and accurately controlling microscale fluids. However, the viscosity chip of the traditional straight channel structure has limitations, and the processing technology is also facing challenges. In this study, a variable cross-section microfluidic chip structure was designed and successfully manufactured by photocuring 3D printing technology. A digital-printed (DP) microfluidic viscometer was realized by a pressure-driven flow combined with optical imaging. The device measures the change in sample viscosity with shear rate by recording the change in pressure and flow velocity with time. The whole experiment requires only 25 μl of reagents per time, and the single experiment time is less than 2 minutes, which not only reduces the consumption of samples dramatically, but also improves the efficiency of the experiment significantly. Compared with commercial viscometers, our measurements are accurate and capable of supporting non-Newtonian fluids. The proposed platform provides good cost-effectiveness and operational simplicity and lays the methodological foundation for viscosity measurements of more complex properties of fluids.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 7","pages":" 1326-1337"},"PeriodicalIF":3.6,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143506824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular combination between alkanolamines and galvinol for ratiometric colorimetric sensing of CO2 gas†","authors":"Ajay Kumar Sharma, Poonam Sharma, Pushkar Mehara and Pralay Das","doi":"10.1039/D4AN01557F","DOIUrl":"10.1039/D4AN01557F","url":null,"abstract":"<p >In this study, the application of alkanolamines as an optical CO<small>₂</small>-responsive medium in combination with galvinol (GALH) as a reversible quantitative colorimetric sensor is proposed. Monoethanolamine (MEA) and diethanolamine (DEA), as the simplest primary (1°) and secondary (2°) alkanolamines, were explored for the colorimetric CO<small>₂</small> response attributed to their well-known CO<small>₂</small> absorption ability on an industrial scale from more than six decades. Further, the anionic form of GALH (GAL<small>⁻</small>) generates an intense purple color that allows its application for colorimetric measurement which has been very less explored for optical sensing purposes. A reversible, convenient, and simplified colorimetric detection of CO<small>₂</small> gas was performed using GALH in combination with MEA and DEA in CH<small>₃</small>CN solvent, which showed limits of detection (LODs) for CO<small>₂</small> gas as low as ∼19 and ∼31 ppm respectively with recyclabilities. The main feature of the developed CO<small>₂</small> sensor is its non-aqueous medium application, which makes it ideal for producing error-free results under different humidity conditions.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 7","pages":" 1318-1325"},"PeriodicalIF":3.6,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496163","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An integrated microfluidic chip for rapid and multiple antimicrobial susceptibility testing†","authors":"Zirui Pang, Lulu Shi, Mingyu Wang and Jifang Tao","doi":"10.1039/D4AN01430H","DOIUrl":"10.1039/D4AN01430H","url":null,"abstract":"<p >The overuse and misuse of antibiotics have caused the development of antimicrobial resistance (AMR), which poses a significant threat to human health. Antimicrobial susceptibility testing (AST) serves as an effective tool for assessing the susceptibility of pathogens infecting patients and guiding the precise use of antibiotics. The conventional AST method, however, is limited by prolonged incubation times and high reagent consumption. In this study, we introduce an integrated microfluidic platform, enabling multiple AST and minimum inhibitory concentration (MIC) determination after 2 hours of incubation. Sample loading is achieved using a self-priming and vacuum-driven approach, enhancing operational feasibility and preventing cross-contamination during reagent pre-coating. Moreover, the use of chips with pre-coated antibiotics minimizes the need for reagent handling off-chip, thereby enhancing the flexibility of the microfluidic device and making the platform easy to use. The AST on-chip results for <em>Klebsiella pneumoniae</em> (<em>K. pneumoniae</em>) S1 correlate well with broth dilution methods. This integrated microfluidic platform offers a novel approach for rapid AST, demonstrating improved customization and efficiency for AST assays. It holds potential for addressing multi-drug resistant bacterial strains and accommodating diverse screening scenarios in modern clinical diagnostics.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 7","pages":" 1398-1408"},"PeriodicalIF":3.6,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elucidating Gas Phase Microstructures of Therapeutic Deep Eutectic System","authors":"Oluseyi Olawuyi, James Stewart, Md. Minhas Hossain Hossain Sakib, William Bryant, Mary-Kate Wewers, Noam Lewit, Md Ackas Ali, Md Sajjadur Rahman, Mohammad A Halim","doi":"10.1039/d4an00645c","DOIUrl":"https://doi.org/10.1039/d4an00645c","url":null,"abstract":"The therapeutic deep eutectic solvent is a new class of deep eutectic solvent (DES), which includes at least an active pharmaceutical ingredient (API) as one of its components. Therapeutic DESs are emerging alternatives that improve the bioavailability, solubility, delivery, and pharmacokinetics properties of drugs. DESs comprise two components, generally hydrogen bond acceptor (HBA) and hydrogen bond donor (HBD), with varying ratios. The interaction chemistry between HBA:HBD in DESs is complex. Moreover, stoichiometry and cluster formation of DES at the molecular level received little attention. Mass spectrometry (MS) is an attractive technique for studying isolated gas phase molecules; however, such investigations have not been implemented for DESs. Compared to other techniques, MS is unique to provide the gas phase stoichiometry, cluster formation, and interaction network between two components of DESs. In addition, computational modeling assists in visualizing the isolated DES clusters and unraveling a deeper understanding of the structure-property relationship. In this study, multi-technique approaches including thermogravimetric (TGA), colorimetric (DSC), spectroscopic (IR and Raman), emerging mass spectrometry, and computational were employed to characterize the menthol:ibuprofen based therapeutics DES. The thermal, colorimetric, and spectroscopies studies showed that hydrogen bonding is the primary factor contributing to DES formation. This study also reported the stable gas phase cluster structure of a menthol: ibuprofen DES using electrospray ionization (ESI) and direct analysis in real time (DART) coupled with mass spectrometry. Subsequently, temperature-dependent DART-MS investigation shows that different temperature conditions impact the formation, intensity of clusters, and the presence of ester impurities. The most intense peak in the ESI-MS and DART-MS spectrum was detected at m/z 363.1, corresponding to the hetero molecular cluster of 1:1 menthol: ibuprofen complex. In addition to the hetero cluster, homo clusters of two-menthol and two-ibuprofen are also detected. Density functional theory (DFT) was employed to investigate the possible gas phase structures of the selected clusters obtained from MS. The DFT results show that hydrogen bonds between the constituents stabilize most of the clusters. MS-guided computational model visualized detailed microstructures and provided insights into the formation mechanism and intermolecular interaction of therapeutic DES.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"12 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143486598","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A steam-mediated isothermal amplification and flocculation-based detection platform for electricity-free point of care diagnostics†","authors":"Kissan D. Achary, Satheesh Natarajan and Aashish Priye","doi":"10.1039/D4AN01526F","DOIUrl":"10.1039/D4AN01526F","url":null,"abstract":"<p >Approximately 9% of the global population lacks access to reliable electricity, and the absence of affordable, electricity-free diagnostic tools hinders early detection of infectious diseases, exacerbating public health burdens in resource-limited settings. We introduce SteamFloc-LAMP – an electricity-free molecular diagnostic platform engineered for instrument-free detection of pathogenic nucleic acid targets. The platform leverages steam-mediated heating from boiling water to sustain the isothermal conditions required for Loop-Mediated Isothermal Amplification (LAMP). Thermal characterization of the steam-mediated heating system identified parameters that enable the consistent maintenance of optimal temperatures for LAMP reactions with minimal fluctuations. Visual end-point detection was achieved through a bridging flocculation mechanism, which exploits the interaction between LAMP amplicons, spermine, and charcoal particles, leading to visible aggregation in positive samples, thus enabling naked-eye detection without the need for specialized equipment or expensive reagents like fluorophores or colorimetric dyes. The SteamFloc-LAMP assay targeted the <em>lip</em>L32 gene, recognized for its exclusivity to pathogenic <em>Leptospira</em> strains. The assay achieved a detection limit of 100 fg of genomic DNA per reaction (∼90 genome copies). Specificity tests using <em>lip</em>L32-specific primers demonstrated the assay's ability to distinguish pathogenic <em>Leptospira</em> accurately, with no cross-reactivity with <em>lig</em>B, <em>lig</em>A, or <em>lip</em>L41 genes found in nonpathogenic strains. A blind test involving DNA extracted from <em>Leptospira</em> reference cultures further validated the assay's diagnostic accuracy, aligning with PCR results. These findings demonstrate the SteamFloc-LAMP assay as a reliable, simple, and cost-effective field deployable diagnostic tool with significant implications for point-of-care detection.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 6","pages":" 1187-1194"},"PeriodicalIF":3.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143477477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"“Repair and fold” DNA nanotweezers for measuring DNA alkylation repair mediated by ALKBH†","authors":"Fengze Jiang, Cui Zhang, Xiangnan Wang, Yuan Yin, Jieling Hong, Hao Tang, Li-Juan Tang and Zhenkun Wu","doi":"10.1039/D5AN00099H","DOIUrl":"10.1039/D5AN00099H","url":null,"abstract":"<p >We report a novel DNA lesion-modified nanotweezer that underwent conformational switching upon ALKBH enzyme-mediated lesion repair. We demonstrated that the DNA lesion-modified nanotweezer enabled specific and rapid monitoring of ALKBH2 and ALKBH3 activities and screening of inhibitors. Importantly, this strategy allowed evaluating ALKBH2-associated drug resistance in cells.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 7","pages":" 1229-1234"},"PeriodicalIF":3.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143477480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 caffeic acid fluorescent probe for detecting laccase in grape juice and mushrooms†","authors":"Haolin Zhang, Zixu He, Xiaofan Zhang and Xiaohua Li","doi":"10.1039/D5AN00071H","DOIUrl":"10.1039/D5AN00071H","url":null,"abstract":"<p >Laccase is a kind of copper-containing polyphenol oxidase obtained with similar properties from different sources, and its catalytic reaction requires only oxygen and releases only water. The most widely used method for laccase detection is spectrophotometric assay with limited sensitivity. Herein, we report a highly sensitive fluorescence method for detecting the activity of laccase. The reported probe shows high selectivity, reliable accuracy and a good linear relationship toward different concentrations of laccase. Upon reaction, a new absorption peak appears around 420 nm accompanied by a significant fluorescence increase at 470 nm, which was consistent with the conjugation extension after the polyphenol structure was oxidized to quinone. The effects of different inhibitors and metal ions on the activity of laccase were assessed and the probe was compared with a commercial laccase detection kit and it showed higher sensitivity. Furthermore, this method was successfully used for the determination of laccase in grape musts with different degrees of fermentation as well as in three kinds of mushroom extracts.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 7","pages":" 1361-1366"},"PeriodicalIF":3.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143477481","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent advances in the electrochemiluminescence detection of small molecule drugs","authors":"Jiali Li, Xinni Yao, Jiateng Ma, Chuang Liu, Wenjun Hong, Haigang Wu, Minjie Li and Liang-Hong Guo","doi":"10.1039/D4AN01562B","DOIUrl":"10.1039/D4AN01562B","url":null,"abstract":"<p >The detection of small molecule drugs is crucial in clinical treatment and environmental protection by facilitating the optimization of therapeutic regimens, preventing adverse drug reactions and monitoring environmental pollution. Electrochemiluminescence (ECL) is widely employed in the detection of small molecule drugs due to its high sensitivity and low background signal. This review highlights advancements from the last five years or so in ECL detection methods based on ECL reactions between luminophores and drugs as well as those based on affinity reactions between recognition molecules and drugs. Studies on affinity-based sensors including immunosensors, aptamer sensors, molecularly imprinted sensors, and composite material sensors are summarized. The review reveals that innovations in ECL luminophores, electrode materials and recognition materials are key areas of focus in this field. Nanomaterials play fundamentally important roles in enhancing the performance of ECL detection by acting as carriers of conventional luminophores, highly efficient luminescent materials, catalytically active electrode materials, and selective and stable recognition elements. With further advances in multiple drug detection, instrument miniaturization, on-site and point of care detection, and therapeutic monitoring, ECL is expected to play more significant roles in the detection of small molecule drugs.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 6","pages":" 1048-1065"},"PeriodicalIF":3.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143477478","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A robust signal processing program for nanopore signals using dynamic correction threshold with compatible baseline fluctuations","authors":"Guohao Xi, Jinmeng Su, Jie Ma, Lingzhi Wu and Jing Tu","doi":"10.1039/D4AN01384K","DOIUrl":"10.1039/D4AN01384K","url":null,"abstract":"<p >Solid-state nanopores represent a powerful platform for the detection and characterization of a wide range of biomolecules and particles, including proteins, viruses, and nanoparticles, for clinical and biochemical applications. Typically, nanopores operate by measuring transient pulses of ionic current during translocation events of molecules passing through the pore. Given the strong noise and stochastic fluctuations in ionic current recordings during nanopore experiments, signal processing based on the statistical analysis of numerous translocation events remains a crucial issue for nanopore sensing. Based on parallel computational processing and efficient memory management, we developed a novel signal processing procedure for translocation events to improve the signal identification performance of solid-state nanopores in the presence of baseline oscillation interference. By using an adaptive threshold within a sliding window, we could correct the baseline determination process in real time. As a result, the features of translocation event signals could be identified more accurately, especially for the intermittent occurrence of high-density complex signals. The program also demonstrated good signal differentiation. As a ready-to-use software, the data program is more efficient and compatible with diverse nanopore signals, making it suitable for more complex nanopore applications.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 7","pages":" 1386-1397"},"PeriodicalIF":3.6,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/an/d4an01384k?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143477479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}