{"title":"Baseline correction of Raman spectral data using triangular deep convolutional networks","authors":"Tiejun Chen, YoungJae Son, Changqing Dong, Sung-June Baek","doi":"10.1039/d5an00253b","DOIUrl":"https://doi.org/10.1039/d5an00253b","url":null,"abstract":"Raman spectroscopy requires baseline correction to address fluorescence and instrumentation-related distortions. Existing baseline correction methods can be broadly classified into traditional mathematical approaches and deep learning-based techniques. While traditional methods often require manual parameter tuning for different spectral datasets, deep learning methods offer greater adaptability and enhance automation. Recent research on deep learning-based baseline correction has primarily focused on optimizing existing methods or designing new network architectures to improve correction performance. This study proposes a novel deep learning network architecture to further enhance baseline correction effectiveness, building upon prior research. Experimental results demonstrate that the proposed method outperforms existing approaches by achieving superior correction accuracy, reducing computation time, and more effectively preserving peak intensity and shape.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"5 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143866299","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}
AnalystPub Date : 2025-04-24DOI: 10.1039/d5an00262a
Rajat Kumar, Federica Piccirilli, Paola Di Pietro, Johannes Schmidt, Giovanni Birarda, Lisa Vaccari, Andrea Perucchi, Prasanta Kumar Datta
{"title":"Broadband terahertz signatures and vibrations of Phe-Phe peptide and its fibrils.","authors":"Rajat Kumar, Federica Piccirilli, Paola Di Pietro, Johannes Schmidt, Giovanni Birarda, Lisa Vaccari, Andrea Perucchi, Prasanta Kumar Datta","doi":"10.1039/d5an00262a","DOIUrl":"https://doi.org/10.1039/d5an00262a","url":null,"abstract":"In recent years, peptide-based nanomaterials gain significant attention in drug discovery due to their promising functionality in biophysical processes and low production costs. Among synthetic short peptides, diphenylalanine (Phe-Phe), a templating block in amyloid fibrils, shows notable self-assembling properties and potential applications in drug delivery and nanostructured biomaterials with interesting functional peculiarities and biocompatibility. Conformational flexibility at ps timescale shapes biomolecules-ligands interactions and represents a useful tool to directly probe biocompatibility and functionality of nanostructured materials. We highlight here the Terahertz (THz) fingerprint of Phe-Phe, demonstrating that several intramolecular and intermolecular ps modes occur between 0.2 and 4 THz. Through the combination of experimental and computational approaches, we get valuable insights into two different assembled forms of Phe-Phe as crystalline commercial powder and after inducing fibrillar self-assembly. Phe-Phe shows a refractive index of about 1.47, and several THz vibrations, belonging to torsions and bending of the intramolecular structure, detect at 0.55, 0.83, 1.13, 1.40, 1.68, 2.18, 2.71, 3.00, and 3.33 THz. Moreover, the observation of a mode at 1.8 THz, assign to intermolecular vibrations, highlights the impact of THz spectroscopy in detecting different assembly states of Phe-Phe.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"8 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143872157","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}
AnalystPub Date : 2025-04-23DOI: 10.1039/d5an00048c
jiaojing Sun, Wenqing Geng, Yueju Wang, Huiling Li, Rong Tan, Yifeng Tu
{"title":"An innovative electrochemiluminescent immunosensor using dual amplified signals from AuNPs@CoSn(OH)6 for the detection of AD-biomarker: amyloid-beta 1-40","authors":"jiaojing Sun, Wenqing Geng, Yueju Wang, Huiling Li, Rong Tan, Yifeng Tu","doi":"10.1039/d5an00048c","DOIUrl":"https://doi.org/10.1039/d5an00048c","url":null,"abstract":"Alzheimer’s disease (AD) is a degenerative condition of the nervous system that causes severe damage to patients’ daily activities as well as the quality of their life. Amyloid beta 1-40 protein (Aβ40), which is involved in the formation of cerebral plaques, is one of the crucial biomarkers related to AD. Herein, a novel and highly sensitive immunosensor for the detection of Aβ40 is developed. Using a reinforced indium tin oxide coated glass by the nanocomposite of gold nanoparticle enhanced CoSn(OH)6 (AuNPs@CoSn(OH)6) to trigger the electrochemiluminescence (ECL) of luminol as the sensing signal, the immunosensor is fabricated by immobilizing the Aβ40 antibody onto it. By integrating the high immune specificity, the excellent conductivity and catalytic activity of nanocomposite, the resultant immunosensor can be successfully employed to detect the target in real samples. The formation of the immune complex leads to increased steric hindrance and electron transfer resistance, which in turn causes a declined ECL output when the target Aβ40 binds to antibody on the sensor surface. Under optimized conditions, the developed ECL immunosensor exhibits a linear response for Aβ40 ranging from 1 to 800 pg/mL and a low detection limit of 0.47 pg/mL. Experimentally, it is demonstrated to be highly sensitive, specific, reproducible and stable. This work extends the application of perovskite CoSn(OH)6 and AuNPs in the field of ECL immunosensing and provides a novel strategy for clinical research on Alzheimer’s disease.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"17 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143862245","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}
AnalystPub Date : 2025-04-22DOI: 10.1039/d5an00372e
Shiting Gu, Zhonghai Zhang
{"title":"Biocompatible AgInS2@hydrogel microelectrode with enhanced photoelectrochemical sensitivity for real-time in vivo dopamine monitoring†","authors":"Shiting Gu, Zhonghai Zhang","doi":"10.1039/d5an00372e","DOIUrl":"https://doi.org/10.1039/d5an00372e","url":null,"abstract":"In situ monitoring of neurochemical dynamics is pivotal for understanding brain function and diagnosing neurological disorders. Conventional photoelectrochemical (PEC) sensors face limitations due to poor tissue compatibility and insufficient light penetration depth in vivo. Herein, we present a transparent and conductive hydrogel-based microelectrode (AgInS2@hydrogel) that integrates a biocompatible topological hydrogel with an AgInS2 semiconductor for selective dopamine (DA) detection. The hydrogel, synthesized via copolymerization of acrylamide and PR-PEGMA crosslinker with PEDOT:PSS as a conductive filler, exhibits tissue-matching elasticity (Young’s modulus ≈118 kPa) and high conductivity (177 mS/m). The AgInS2 semiconductor, in situ grown on the hydrogel surface, generates reactive oxygen species under visible light, triggering DA polymerization into polydopamine (PDA). This process establishes a self-enhancing feedback loop between AgInS2 and PDA, enabling selective DA detection with a linear range of 0.2–4 μM and limit of detection of 64 nM. Implanted into the mouse striatum, the sensor successfully tracked dynamic DA fluctuations induced by nomifensine maleate, demonstrating its capability for real-time in vivo neurochemical analysis. This work advances the development of minimally invasive, high-sensitivity tools for brain research.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"76 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858192","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}
AnalystPub Date : 2025-04-22DOI: 10.1039/d5an00220f
Ying Zhu, Ran Li, Zhongshuai Zhao, Zhongde Liu
{"title":"Headspace separation–combined fluorescence strategy for highly selective detection of hydrogen sulfide using silver nanocluster assemblies as a probe via a self-made device","authors":"Ying Zhu, Ran Li, Zhongshuai Zhao, Zhongde Liu","doi":"10.1039/d5an00220f","DOIUrl":"https://doi.org/10.1039/d5an00220f","url":null,"abstract":"Hydrogen sulfide (H<small><sub>2</sub></small>S) is a poisonous gas and endogenously produced signaling molecule in mammalian systems, and its highly selective and rapid monitoring is urgently desired. Nevertheless, the performance of nearly all the fluorescence probes for H<small><sub>2</sub></small>S detection is limited by interferences caused by other non-volatile thiol-containing species. To address this issue, herein, a headspace separation–combined fluorescence strategy was attempted by utilizing thiosalicylic acid (TSA)-capped silver nanoclusters (AgNCs@TSA) as probes. AgNCs@TSA showed a significant aggregation-induced emission (AIE) phenomenon; Moreover, upon the introduction of H<small><sub>2</sub></small>S, the responsive disassembly of its aggregates occurred due to the competitive Ag–sulfur bond formation between H<small><sub>2</sub></small>S and TSA molecules on the surface of the AgNCs, accompanied by a distinctive luminescence quenching. Using hybrid analysis, superior selectivity could be obtained, and the signal change (Δ<em>I</em>) of AgNCs@TSA showed good linearity at an H<small><sub>2</sub></small>S concentration of 0.1–100 μM with a detection limit (3<em>σ</em>) of 72.2 nM. In monitoring sulfide levels in real samples, the approach yielded recoveries from 98.3% to 103.7% with a relative standard deviation (RSD) of less than 3.1%. The approach described here may be readily extended to the analysis of other volatile components, with the advantage of easy elimination of interferences. Furthermore, the hybrid optical strategy is expected to be a flexible and versatile platform for the on-site detection of volatile components.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"108 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858189","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}
AnalystPub Date : 2025-04-22DOI: 10.1039/d5an00107b
Ella Mahlamäki, Inge Schlapp-Hackl, Tharindu Koralage, Michael Hummel, Mikko Mäkelä
{"title":"Spectral imaging and a one-class classifier for detecting elastane in cotton fabrics","authors":"Ella Mahlamäki, Inge Schlapp-Hackl, Tharindu Koralage, Michael Hummel, Mikko Mäkelä","doi":"10.1039/d5an00107b","DOIUrl":"https://doi.org/10.1039/d5an00107b","url":null,"abstract":"Elastane detection is important for textile recycling as elastane fibers can hamper mechanical and chemical fiber recycling. Here, we report the use of near-infrared imaging spectroscopy and class modelling to detect 2–6% elastane in consumer cotton fabrics to provide alternatives to current detection methods, which are invasive and time-consuming. Our method automatically identified outlier fabrics and measurements with class-specific clustering and showed higher classification accuracies by averaging across individual pixel spectra to reduce sampling uncertainty. The final classification results showed median test set true positive and true negative rates of 89–97% based on randomized resampling. Class modelling offers clear benefits compared to commonly used discriminant classifiers as it allows modelling new classes using only a set of target samples without requiring representative training objects from all the other classes. Overall, these results open the possibility for fast non-invasive detection of small amounts of elastane in cotton, taking us a step closer to a circular economy of textiles.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"22 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858193","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":"Metal-Organic Framework Decorated Whispering-Gallery-Mode Microsphere Cavity for VOCs Sensing","authors":"Xianggang Chen, Xiaoyan Zhang, Xiaoyi Wu, Ling Bai, Yin Yin","doi":"10.1039/d5an00102a","DOIUrl":"https://doi.org/10.1039/d5an00102a","url":null,"abstract":"Metal-organic frameworks (MOFs) decorated whispering gallery mode (WGM) microcavities are prepared for volatile organic compounds (VOCs) sensing. The composite microcavity is sensitive to the refractive index changes caused by VOCs adsorptions, with a sensitivity of 9.74 nm/RIU, a detection limit of 3.30×10-3 RIU, robust reproducibility, and good resistance to humidity or temperature variations.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"38 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858194","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":"Sarin simulants show very limited representativeness","authors":"Valentin Bureau, Sébastien Penlou, Sonia de Sousa Nobre, Alexandre Carella, Jean-Pierre Simonato","doi":"10.1039/d5an00225g","DOIUrl":"https://doi.org/10.1039/d5an00225g","url":null,"abstract":"In this study, we conducted colorimetric gas phase tests on real sarin and compared the results with the most commonly used simulants under identical test conditions. Our findings indicate that reactivity extrapolation is not a reasonable approach and that validation on real toxic gas remains essential for a fair assessment of sarin sensors.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"3 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858198","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}
AnalystPub Date : 2025-04-22DOI: 10.1039/d5an00035a
Renu Poria, Ankur Kaushal, Shruti Verma, Selva Kumar Ramasamy, G. S. Ghodake, Deepak Kumar, Shagun Gupta
{"title":"GQD/g-C3N4-modified nanochip for electrochemical detection of Dengue serotype 3","authors":"Renu Poria, Ankur Kaushal, Shruti Verma, Selva Kumar Ramasamy, G. S. Ghodake, Deepak Kumar, Shagun Gupta","doi":"10.1039/d5an00035a","DOIUrl":"https://doi.org/10.1039/d5an00035a","url":null,"abstract":"A graphene quantum dot/2D graphitic carbon nitride (GQD)/g-C3N4)-based ultrasensitive DNA biosensor was constructed using 5’ aminated DNA probes immobilized onto the surface of a screen-printed paper electrode (SPPE) for the detecting DENV 3 (dengue serotype 3). FTIR, UV‒Vis, TEM, and particle size measurements were used to characterize the synthesized nanocomposites. These results were then used to fabricate an affordable DNA sensor based on SPPE that detects DENV 3. Initially, bioinformatics methods were used to develop DNA probes unique to DENV 3. The findings indicated that the most effective DNA probe for identifying DENV 3 was a 20-nucleotide sequence which was immobilized onto the GQD/g-C3N4-modified SPPE. The electrochemical response was studied via differential pulse voltammetry (DPV) and cyclic voltammetry (CV). Electrode surface at each step of fabrication was characterized via FE‒SEM, EIS and FTIR. The developed DNA sensor showed excellent analytical performance in terms of LOD and sensitivity. With CV, the LOD was 1 pg/µl, with a sensitivity of 7993 ng/μA/mm2. However, with DPV, the LOD and sensitivity were 1 pg/µl and 11,116 ng/μA/mm2, respectively. This method should be preferable in the future for detecting DENV 3 in biological and clinical samples.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"33 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858190","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}
AnalystPub Date : 2025-04-22DOI: 10.1039/d4an01415d
Seth R. T. Zima, Rithvik V. Turaga, Sofia C. Yeates-Delahoz, Jose M. Ayuso
{"title":"Microfluidic platform for rapid multiplexed biological sample handling for molecular interrogation","authors":"Seth R. T. Zima, Rithvik V. Turaga, Sofia C. Yeates-Delahoz, Jose M. Ayuso","doi":"10.1039/d4an01415d","DOIUrl":"https://doi.org/10.1039/d4an01415d","url":null,"abstract":"Cell manufacture and immune cell research often require screening large numbers of analytes like proteins, metabolites, and nucleic acids, which usually entail expensive equipment and labor-intensive assays such as flow cytometry. On the other hand, microfluidic devices can generate numerous readouts with reduced sample volume, however they often require specialized equipment and expertise to fabricate and use. To this end, we have designed a microfluidic device based on a well plate design for multiplexed analysis of biochemical analyte readouts. The device enables simultaneous liquid delivery to multiple individual wells, thus reducing the number of pipetting steps required to perform assays. The capillary valves used to confine liquid within the wells are capable of withstanding freeze-thawing, which enables pre-loading of plates with reagent for storage and later use. We performed a bioluminescence ATP assay to quantify T cell viability and found that the device was able to capture the luminescence signal with a high degree of consistency. Finally, we performed a bioluminescence immunoassay to compare secretion of IFN-γ between naïve and activated CD4+ T cells, thereby highlighting the potential for this technology to measure relevant immune markers.","PeriodicalId":63,"journal":{"name":"Analyst","volume":"18 1","pages":""},"PeriodicalIF":4.2,"publicationDate":"2025-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143858191","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}