Analyst最新文献

{"title":"Designing a novel paper-based microfluidic disc for rapid and simultaneous determination of multiple nutrient salts in water†","authors":"Zhentao Sun, Youquan Zhao, Yameng Liu, Chen Chen and Hao Chen","doi":"10.1039/D4AN01127A","DOIUrl":"10.1039/D4AN01127A","url":null,"abstract":"<p >In the face of worsening water quality and escalating water environmental emergencies, this study developed a paper-based microfluidic disk for rapid, on-site determination of ammonia nitrogen, nitrates, nitrites, and phosphates in water. The method utilizes centrifugal microfluidics and paper-based technology, thus simplifying the operation while eliminating the need for on-site reagent preparation. Experimental results demonstrate that the disk requires only 80 microliters of a water sample and 2 minutes to complete the quantitative analysis of the four nutrients, with a coefficient of variation below 1.72% and spike recoveries ranging from 92% to 113%. The development of the disk provides an effective and rapid, on-site testing tool for water quality analysis.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 22","pages":" 5563-5571"},"PeriodicalIF":3.6,"publicationDate":"2024-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142439205","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":"Imaging specific proteins in living cells with small unnatural amino acid attached Raman reporters†","authors":"Erli Cai, Yage Chen, Jing Zhang, Haozheng Li, Yiran Li, Shuai Yan, Zhiyong He, Quan Yuan and Ping Wang","doi":"10.1039/D4AN00758A","DOIUrl":"10.1039/D4AN00758A","url":null,"abstract":"<p >Fluorescence labeling <em>via</em> fluorescent proteins (FPs) or immunofluorescence has been routinely applied for microscopic imaging of specific proteins. However, due to these over-weight and oversized labels (<em>e.g.</em> GFP, 238 aa, 27 kDa, ∼4 nm in size), the potential physiological malfunctions of the target proteins are largely underestimated in living cells. Herein, for living cells, we report a small and minimally-invasive Raman reporter (about 2 aa and &lt;1 kDa), which can be site-specifically introduced into proteins by genetic codon expansion. After a single unnatural amino acid (UAA) is precisely incorporated into the target protein, the strained alkyne can rapidly undergo copper-free Diels–Alder cycloaddition reactions with the tetrazine-functionalized Raman reporter, which features a fine vibrational spectrum in contrast to fluorescence. In our experimental results, the UAA-based Raman tag was successfully incorporated into vimentin, histone 3.3 and huntingtin (Htt74Q) proteins in living HeLa cells and further utilized for stimulated Raman imaging. The site-specific bioorthogonal fusion of small Raman tags with intracellular proteins will pave the way for minimally-invasive protein labeling and multi-color imaging in living cells.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 22","pages":" 5476-5481"},"PeriodicalIF":3.6,"publicationDate":"2024-10-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142431164","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":"Probing the role of ligation and exonuclease digestion towards non-specific amplification in bioanalytical RCA assays†","authors":"Vandana Kuttappan Nair, Chandrika Sharma, Shrawan Kumar, Mrittika Sengupta and Souradyuti Ghosh","doi":"10.1039/D4AN00866A","DOIUrl":"10.1039/D4AN00866A","url":null,"abstract":"<p >Non-specific amplification (NSA, amplification in the absence of a target analyte) in bioanalytical rolling circle amplification (RCA) assays, especially those involving pre-synthesized circular DNA (cDNA), affects its analytical sensitivity. Despite extensive development of RCA-based bioanalytical methods, the NSA in RCA remains uncharacterized in terms of its magnitude or origin. NSA may originate from inefficient ligation or succeeding cDNA purification steps. This study comprehensively quantifies NSA across several ligation and digestion techniques for the first time since the innovation of RCA. To quantify the NSA in RCA, cDNAs were prepared using self-annealing, splint-padlock, or cohesive end ligations. The cDNAs were then subjected to nine different exonuclease digestion steps and quantified for NSA under linear as well as hyperbranched RCA conditions. We investigated buffer compositions, divalent ion concentrations, single or dual enzyme digestion, cohesive end lengths, and splint lengths. The optimized conditions successfully mitigated absolute NSA by 30–100-fold and relative NSA (normalized against primer-assisted RCA) to ∼5%. Besides understanding the mechanistic origin of NSA, novel aspects of enzyme–substrate selectivity, buffer composition, and the role of divalent ions were discovered. With increasing bioanalytical RCA applications, this study will help standardize NSA-free assays.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 22","pages":" 5491-5503"},"PeriodicalIF":3.6,"publicationDate":"2024-10-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142397725","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":"Nanozyme linked multi-array gas driven sensor for real-time quantitative detection of Group A streptococcus†","authors":"Qi Wang, Pei Liu, Ke Xiao, Wenying Zhou, Jinfeng Li and Yun Xi","doi":"10.1039/D4AN00787E","DOIUrl":"10.1039/D4AN00787E","url":null,"abstract":"<p > <em>Group A streptococcus</em> (<em>GAS</em>) is a pathogen typically transmitted through respiratory droplets and skin contact, causing an estimated 700 million mild non-invasive infections worldwide each year. There are approximately 650 000 infections that progress to severe invasive infections, even resulting in death. Therefore, the ability to detect <em>GAS</em> rapidly, accurately and in real time is important. Herein, we developed a nanozyme linked multi-array gas driven sensor (NLMAGS) to point-of-care testing of <em>GAS</em> within 2 h. The NLMAGS demonstrated excellent performance as it combined the advantages of nanozyme techniques, immunoassay techniques, and 3D printing techniques. Platinum- and palladium-rich nanozyme particles (Au@Pt@PdNPs) were synthesized and used to label monocloning antibodies as detection probes. Magnetic beads were labeled with monocloning antibodies as capture probes to establish a double-antibody sandwich immunoassay for the detection of <em>GAS</em>. The sandwich immune complex can catalyze the H<small>₂</small>O<small>₂</small> substrate and produce O<small>₂</small>. <em>GAS</em> quantification can be achieved by measuring the distance that the O<small>₂</small> pushes the ink drops forward in the sensor. Under optimized conditions, the NLMAGS quantitatively detected 24 spiked samples with a limit of detection (LOD) of 62 CFU mL<small>⁻¹</small>, which was 5 times lower than that of ELISA (334 CFU mL<small>⁻¹</small>). A strong correlation with the conventional ELISA was found (<em>r</em> = 0.99, <em>P</em> &lt; 0.001). In comparison, the traditional lateral flow immunoassay based on Au@Pt@PdNPs-mAb2 (Au@Pt@PdNPs-LFIA) had a LOD of 10<small>⁴</small> CFU mL<small>⁻¹</small>, which was significantly higher than that of NLMAGS. The NLMAGS demonstrated excellent sensitivity to <em>GAS</em>. The intra- and inter-assay precisions of the sensor were below 15%. Overall, the established NLMAGS has promising potential as a rapid and quantitative method for detecting <em>GAS</em> and can also be used to detect various pathogens.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 22","pages":" 5433-5442"},"PeriodicalIF":3.6,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142385075","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":"Material-agnostic characterization of spatially offset Raman spectroscopy in turbid media via Monte Carlo simulations†","authors":"Zuriel Erikson Joven, Piyush Raj and Ishan Barman","doi":"10.1039/D4AN01044B","DOIUrl":"10.1039/D4AN01044B","url":null,"abstract":"<p >Spatially offset Raman spectroscopy (SORS) is a transformative method for probing subsurface chemical compositions in turbid media. This systematic study of Monte Carlo simulations provides closed-form characterizations of key SORS parameters, such as the distribution of spatial origins of collected Raman photons and optimal SORS geometry to selectively interrogate a subsurface region of interest. These results are unified across an extensive range of material properties by multiplying spatial dimensions by the medium's effective attenuation coefficient, which can be calculated when the absorption and reduced scattering coefficients are known from the literature or experimentation. This method of spatial nondimensionalization is validated <em>via</em> goodness-of-fit analysis on the aggregate models and by training a subsurface sample localization model on a heterogeneous population of materials. The findings reported here advance the understanding of SORS phenomena while providing a quantitative and widely applicable foundation for designing and interpreting SORS experiments, facilitating its application in disciplines such as biomedical, materials science, and cultural heritage fields.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 22","pages":" 5463-5475"},"PeriodicalIF":3.6,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142384140","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":"Integration of paper-based analytical devices with digital microfluidics for colorimetric detection of creatinine†","authors":"Larissa G. Velasco, Danielly S. Rocha, Richard P. S. de Campos and Wendell K. T. Coltro","doi":"10.1039/D4AN00688G","DOIUrl":"10.1039/D4AN00688G","url":null,"abstract":"<p >Digital microfluidics (DMF) is a platform that enables the automated manipulation of individual droplets of sizes ranging from nanoliter to microliter and can be coupled with numerous techniques, including colorimetry. However, although the DMF electrode architecture is highly versatile, its integration with different analytical methods often requires either changes in sample access, top plate design, or the integration of supplementary equipment into the system. As an alternative to overcome these challenges, this study proposes a simple integration between paper-based analytical devices (PADs) and DMF for automated and eco-friendly sample processing aiming at the colorimetric detection of creatinine (CR, an important biomarker for kidney disease) in artificial urine. An optimized and selective Jaffé reaction was performed on the device, and the reaction products were delivered to the PAD, which was subsequently analyzed with a bench scanner. The optimal operational parameters on the DMF platform were a reaction time of 45 s with circular mixing and image capture after 5 min. Under optimized conditions, a linear behavior was obtained for creatinine concentrations ranging from 2 to 32 mg dL<small>⁻¹</small>, with limits of detection and quantitation equal to 1.4 mg dL<small>⁻¹</small> and 2.0 mg dL<small>⁻¹</small>, respectively. For the concentration range tested, the relative standard deviation varied from 2.5 to 11.0%, considering four measurements per concentration. CR-spiked synthetic urine samples were subjected to analysis <em>via</em> DMF-PAD and the spectrophotometric reference method. The concentrations of CR determined using both analytical techniques were close to the theoretical values, with the resultant standard deviations of 2–9% and 1–4% for DMF-PADs and spectrophotometry, respectively. Furthermore, the recovery values were within the acceptable range, with DMF-PADs yielding 96–108% and spectrophotometry producing 95–102%. Finally, the greenness of the DMF-PAD and spectrophotometry methods was evaluated using the Analytical Greenness (AGREE) metric software, in which 0.71 and 0.51 scores were obtained, respectively. This indicates that the proposed method presents a higher greenness level, mainly due to its miniaturized characteristics using a smaller volume of reagent and sample and the possibility of automation, thus reducing user exposure to potentially toxic substances. Therefore, the DMF-PADs demonstrated great potential for application in the clinical analysis of creatinine, aiding in routine tests by introducing an automated, simple, and environmentally friendly process.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 1","pages":" 60-68"},"PeriodicalIF":3.6,"publicationDate":"2024-10-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142384141","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":"Double-channel sensors for high precision measurement of methane based on a dual-path Herriott cell","authors":"Hongliang Ma, Shiqi Wang, Gaoxuan Wang, Qilei Zhang, Shenlong Zha, Xueyuan Cai, Lingli Li, Pan Pan, Qiang Liu and Shengbao Zhan","doi":"10.1039/D4AN01107D","DOIUrl":"10.1039/D4AN01107D","url":null,"abstract":"<p >A double-channel methane (CH<small>₄</small>) sensor was developed using a dual-pass multipass cell (DP-MPC) and a novel method that combines averaging dual-channel concentration signals with optimized detector gain configuration. This DP-MPC features two input/output coupling holes, resulting in absorption path lengths of approximately 95.8 m and 35.8 m, respectively. By optimizing the photodetector gain configuration and averaging the dual-channel concentration signals, the detection performance of the sensor was further enhanced. Allan deviation analysis indicated that after optimizing the detector gain, the measurement precision after dual-channel averaging reaches 21 ppb with an integration time of 1 s at a concentration of 2 ppm CH<small>₄</small>, which is approximately 1.4 times higher than the measurement precision of the long-path channel (31 ppb) and short-path channel (30 ppb). The time required to achieve a measurement precision of 21 ppb is 2.4 s for the long-path channel and 2.1 s for the short-path channel. The response speed of the dual-channel averaging is approximately 2 times that of any single channel. Meanwhile, the sensor demonstrated its stability and reliability through continuous outdoor atmospheric CH<small>₄</small> measurements.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 22","pages":" 5527-5534"},"PeriodicalIF":3.6,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142383914","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":"Effects of media composition and light exposure on the electrochemical current response during scanning electrochemical microscopy live cell imaging†","authors":"Nikita Thomas, Mengzhen Lyu, Jadon Khouv, Dhésmon Lima and Sabine Kuss","doi":"10.1039/D4AN01075B","DOIUrl":"10.1039/D4AN01075B","url":null,"abstract":"<p >Scanning Electrochemical Microscopy (SECM) has been used as a non-invasive electrochemical technique for studying cellular processes. SECM enables the quantification of cellular metabolites in real-time providing a deeper understanding of cellular responses to external stimuli. SECM imaging of living cells requires maintaining an ideal physiological environment to ensure reliable data collection on cellular reactivity. The cellular response can be directly influenced by physicochemical parameters including cell media composition, temperature and light exposure. This research demonstrates the effect of media composition on the electrochemical current signal of adenocarcinoma cervical cancer (HeLa) cells during SECM measurements using ferrocenemethanol as a redox mediator. Investigated media that are commonly used as electrolyte, are phosphate buffered saline (PBS), and Dulbecco's modified Eagle's medium (DMEM) in the absence and presence of fetal bovine serum (FBS). In addition, this research demonstrates that fluctuating light illumination impacts the stability of the cellular electrochemical current response. Our findings reveal that media composition and illumination are important parameters that must be carefully considered and monitored during SECM live cell imaging.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 22","pages":" 5555-5562"},"PeriodicalIF":3.6,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142383965","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":"Microfluidic methods for the diagnosis of acute respiratory tract infections","authors":"Kan-Zhi Liu, Ganghong Tian, Alex C.-T. Ko, Matthias Geissler, Lidija Malic, Byeong-Ui Moon, Liviu Clime and Teodor Veres","doi":"10.1039/D4AN00957F","DOIUrl":"10.1039/D4AN00957F","url":null,"abstract":"<p >Acute respiratory tract infections (ARTIs) are caused by sporadic or pandemic outbreaks of viral or bacterial pathogens, and continue to be a considerable socioeconomic burden for both developing and industrialized countries alike. Diagnostic methods and technologies serving as the cornerstone for disease management, epidemiological tracking, and public health interventions are evolving continuously to keep up with the demand for higher sensitivity, specificity and analytical throughput. Microfluidics is becoming a key technology in these developments as it allows for integrating, miniaturizing and automating bioanalytical assays at an unprecedented scale, reducing sample and reagent consumption and improving diagnostic performance in terms of sensitivity, throughput and response time. In this article, we describe relevant ARTIs—pneumonia, influenza, severe acute respiratory syndrome, and coronavirus disease 2019—along with their pathogenesis. We provide a summary of established methods for disease diagnosis, involving nucleic acid amplification techniques, antigen detection, serological testing as well as microbial culture. This is followed by a short introduction to microfluidics and how flow is governed at low volume and reduced scale using centrifugation, pneumatic pumping, electrowetting, capillary action, and propagation in porous media through wicking, for each of these principles impacts the design, functioning and performance of diagnostic tools in a particular way. We briefly cover commercial instruments that employ microfluidics for use in both laboratory and point-of-care settings. The main part of the article is dedicated to emerging methods deriving from the use of miniaturized, microfluidic systems for ARTI diagnosis. Finally, we share our thoughts on future perspectives and the challenges associated with validation, approval, and adaptation of microfluidic-based systems.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 1","pages":" 9-33"},"PeriodicalIF":3.6,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/an/d4an00957f?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142383915","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}

{"title":"A nano-biosensing platform based on CuS-BSA for label-free fluorescence detection of Escherichia coli†","authors":"Xiaoqing Zhang, Shanglin Li and Mei Liu","doi":"10.1039/D4AN01060D","DOIUrl":"10.1039/D4AN01060D","url":null,"abstract":"<p >Bacterial contamination is a serious issue for public health and food safety. In this work, a simple and label-free fluorescence detection nanoplatform for <em>Escherichia coli</em> (<em>E. coli</em>) was established on the basis of the competitive relationship for the reduction of Cu<small>²⁺</small> in CuS-BSA between <em>E. coli</em> and <em>O</em>-phenylenediamine (OPD). OPD could be directly oxidized by Cu<small>²⁺</small> to produce 2,3-diaminophenazine (ox OPD) with fluorescence properties. When OPD was introduced into an aqueous solution containing CuS-BSA and <em>E. coli</em>, the oxidation of OPD was inhibited owing to the reduction of Cu<small>²⁺</small> to Cu<small>⁺</small>/Cu<small>⁰</small> by NADH-2 dehydrogenase in the bacterial copper homeostasis mechanism, thus decreasing the fluorescence response signal of the system. Meanwhile, our strategy exhibited a satisfactory performance with a broad linear response to <em>E. coli</em> ranging from 12 to 1.2 × 10<small>⁷</small> CFU mL<small>⁻¹</small>, and the limit of detection was 9 CFU mL<small>⁻¹</small>. The practicability of the developed fluorescence biosensing platform in real samples was evaluated by successful determination of <em>E. coli</em> in drinking water and orange juice. These findings provide a new sensing strategy for analyzing other foodborne bacteria and ensuring food safety assessment.</p>","PeriodicalId":63,"journal":{"name":"Analyst","volume":" 22","pages":" 5394-5400"},"PeriodicalIF":3.6,"publicationDate":"2024-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142379509","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}