Analytical Sciences最新文献

{"title":"Effect of the alkyl chain length of α,ω-dichloroalkane on the Gibbs energy of transfer for functional groups.","authors":"Kohei Uematsu, Erina Tanaka, Takanari Tanaka, Hajime Katano","doi":"10.1007/s44211-024-00656-x","DOIUrl":"https://doi.org/10.1007/s44211-024-00656-x","url":null,"abstract":"<p><p>Ion-transfer reactions of alkyl and perfluoroalkyl carboxylate ions (CH<sub>3</sub>(CH<sub>2</sub>)<sub>n-2</sub>COO<sup>-</sup> with n = 8-12 and CF<sub>3</sub>(CF<sub>2</sub>)<sub>n-2</sub>COO<sup>-</sup> with n = 3-9) were investigated at the polarized Cl-(CH<sub>2</sub>)<sub>m</sub>-Cl with m = 2, 4, 6, and 8 (O) | water (W) interface to evaluate the effects of n and m on the solvation energy of the ions, as well as on their methylene and terminal groups. These ions exhibited reversible or quasi-reversible voltammetric waves due to their transfer across the O | W interfaces, enabling the determination of formal potentials and formal Gibbs transfer energies from O to W, <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> The <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> values for CH<sub>3</sub>(CH<sub>2</sub>)<sub>n-2</sub>COO<sup>-</sup> and CF<sub>3</sub>(CF<sub>2</sub>)<sub>n-2</sub>COO<sup>-</sup> increased linearly with n, allowing the estimation of <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> for methylene and difluoromethylene groups, <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> (CH<sub>2</sub>) and <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> (CF<sub>2</sub>), and for their terminal groups, <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> (COO<sup>-</sup>  + CH<sub>3</sub>) and <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> (COO<sup>-</sup> + CF<sub>3</sub>). Whereas the <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> (CH<sub>2</sub>) and <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> (CF<sub>2</sub>) hardly changed with the variation in m, the <math><mrow><mi>Δ</mi> <msubsup><mi>G</mi> <mrow><mrow><mtext>tr,o</mtext> <mo>→</mo> <mtext>w</mtext></mrow> </mrow> <msup><mn>0</mn> <mo>'</mo></msup> </msubsup> </mrow> </math> (COO<sup>-</sup> + CH<sub>3</sub>) ","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142118771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recent technical development for on-site analysis.","authors":"Mao Fukuyama","doi":"10.1007/s44211-024-00628-1","DOIUrl":"https://doi.org/10.1007/s44211-024-00628-1","url":null,"abstract":"","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142091424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chemical composition combined with network pharmacology and quality markers analysis for the quality evaluation of Qing-fei-da-yuan granules.","authors":"Huanbo Cheng, Ying Liu, Mengling Xu, Ruixue Shi, Lifei Hu, Yuanming Ba, Guangzhong Wang","doi":"10.1007/s44211-024-00592-w","DOIUrl":"10.1007/s44211-024-00592-w","url":null,"abstract":"<p><p>Qing-fei-da-yuan granules (QFDYGs) had been proved to be an effective TCM prescription for treating coronavirus disease 2019 (COVID-19), which are composed of a variety of TCMs, and characterized by multiple components, multiple targets and overall regulation. It is meaningful to further study the chemical composition and pharmacology of QFDYGs for quality evaluation. However, due to the complexity of the components of QFDYGs, there are no reliable and simple analytical methods for current quality evaluation. In this work, antipyretic activity assessment of QFDYGs in the LPS-induced New Zealand rabbit model was carried out to verify the efficacy firstly. It was proved that QFDYGs can be used to relieve fever to help preventing or controlling the prevalence of influenza and pneumonia. Subsequently, UHPLC-ESI-QTOF-MS/MS combined with network pharmacology, quality markers and fingerprint analysis were used to establish the quality control condition. The chemical compositions were analyzed by UHPLC-ESI-QTOF-MS/MS, and 79 of them were identified, such as arecoline, mangiferin, paeoniflorin, etc. Then, the network pharmacology strategy based on 45 candidate components (CCs) in conjunction with influenza and pneumonia diseases was employed to screen the potential active ingredients. According to the drug-CCs-genes-diseases (D-CCs-G-D) networks, baicalein, honokiol, baicalin, paeoniflorin, saikosaponin A, glycyrrhizic acid and hesperidin were selected as quality markers. And a method for content determination of the 7 quality markers was established by optimizing extraction methods, chromatographic conditions and methodological verification. Finally, the quality of 15 batches of QFDYGs was evaluated by using the 7 quality markers combined with fingerprints and principal component analysis (PCA). The analyzed results showed that baicalin, paeoniflorin, glycyrrhizic acid and hesperidin were the high content and stable quality markers. QFDYGs were characterized by overall consistency and individual ingredient differences among the 15 batches. Our quality evaluation study will provide reference for the further development and research of QFDYGs.</p>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141756683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of an HPLC device with water/acetonitrile with NaCl mixed solution that induces a phase-separation multiphase flow as the eluent in the separation column.","authors":"Ryuto Hirose, Takeshi Iharada, Kazuhiko Tsukagoshi","doi":"10.1007/s44211-024-00599-3","DOIUrl":"10.1007/s44211-024-00599-3","url":null,"abstract":"<p><p>We developed a novel HPLC device where the phase-separation multiphase flow worked as the eluent in the separation column by using a water/acetonitrile/ethyl acetate triple mixed solution as a dual-phase-separation solution. Dual-phase-separation solutions form a phase-separation multiphase flow in a microscopic space. The new separation mechanism in the HPLC is called phase-separation mode. In this study, we used water and acetonitrile with NaCl mixed solution as a dual-phase-separation solution instead of the triple mixed solution. Octadecylsilyl (ODS)-modified particle- and porous silica particle-packed separation columns were united with the HPLC device for phase-separation mode caused by phase-separation multiphase flow. NA (1-naphthol) and NDS (2,6-naphthalenedisulfonic acid) were analyzed by the device as model sample. Using the water and acetonitrile with NaCl mixed solution at the solvent volume ratio of 5:5, NA and NDS were not separated on either column at 25 °C. On the other hand, they were separated with the order NDS and NA on the ODS column and separated with the order NA and NDS on the silica column in phase-separation mode at 0 °C. We discuss the separation mechanism of phase-separation mode using the water and acetonitrile with NaCl mixed solution at 0 °C.</p>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141154309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of absorption spectrophotometry of iron(III) in environmental water and sediments using NEDA and its application to the field.","authors":"Michiko Egawa, Shogo Sugahara, Keiya Miwa, Ja Yeong Park, Yukiko Senga, Yasushi Seike","doi":"10.1007/s44211-024-00598-4","DOIUrl":"10.1007/s44211-024-00598-4","url":null,"abstract":"<p><p>In this study, we developed a simple method that enables iron(III) in environmental water to be directly determined via spectrophotometry. In water samples, iron(III) formed a yellowish complex with N-1-Naphthylethylenediamine dihydrochloride (NEDA) at pH 2.0-2.8, the maximum absorption wavelength of which was 462 nm. Detection sensitivity increased in the presence of chloride ions and remained constant for 2-24 h with 0.05-0.57 mol L^-1 chloride. Therefore, NEDA solution containing chloride ions was used as a chromogenic reagent for the determination of iron(III). The determination range for this method was 0.1-20 mgFe(III) L^-1 in a 5 cm glass cell. The developed method is highly selective for iron(III) and has been successfully applied to freshwater, brackish water, seawater, turbid water in rivers, as well as to riverbed and freshwater lake sediments. In addition, a combination of the proposed NEDA method and the 1,10-phenanthroline method enabled simultaneous determination of iron(III) and iron(II).</p>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141160306","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid quantitative analysis of coal composition using laser-induced breakdown spectroscopy coupled with random forest algorithm.","authors":"Hongkun Du, Shaoying Ke, Wei Zhang, Dongfeng Qi, Tengfei Sun","doi":"10.1007/s44211-024-00610-x","DOIUrl":"10.1007/s44211-024-00610-x","url":null,"abstract":"<p><p>Coal is the primary energy source in China, widely used in energy production, industrial processes, and chemical engineering. Due to the complexity and diversity of coal quality, there is an urgent need for new technologies to achieve rapid and accurate detection and analysis of coal, aiming to improve coal resource utilization and reduce pollutant emissions. This study proposes a rapid quantitative analysis of coal using laser-induced breakdown spectroscopy combined with the random forest algorithm. Firstly, a Q-switched Nd: YAG laser at 1064 nm was employed to ablate coal samples, generating plasma, and spectral data were collected using a spectrometer. Secondly, the study explores the impact of different parameters in the preprocessing method (wavelet transform) on the predictive performance of the random forest model. It identifies elements related to coal ash content and calorific value along with their spectral information. Subsequently, to further validate the predictive performance of the model, a comparison is made with models established using support vector machine, artificial neural network, and partial least squares. Finally, under optimal parameters for spectral information preprocessing (wavelet transform with Db4 as the base function and 3 decomposition levels), a model combining wavelet transform with Random Forest is established to predict and analyze the ash content and calorific value of coal. The results demonstrate that the Wavelet Transform-Random Forest model exhibits excellent predictive performance (coal ash content: R² = 0.9470, RMSECV = 4.8594, RMSEP = 4.8450; coal calorific value: R² = 0.9485, RMSECV = 1.5996, RMSEP = 1.5949). Therefore, laser-induced breakdown spectroscopy combined with the random forest algorithm is an effective method for rapid and accurate detection and analysis of coal. The predicted coal composition values show high accuracy, providing insights and methods for coal composition monitoring and analysis.</p>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141247305","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A sensitive and selective voltammetric method for the detection of pyrogallol in tomato and water samples using platinum electrode modified with alizarin red S film.","authors":"Mohammad Amayreh, Muayad Esaifan, Mohammed Khair Hourani","doi":"10.1007/s44211-024-00606-7","DOIUrl":"10.1007/s44211-024-00606-7","url":null,"abstract":"<p><p>In contrast to the hyperactive platinum electrode, ARS modified platinum electrode presents a remarkable inertness toward adsorption and surface processes and lends it for further voltammetric applications. Measuring pyrogallol levels in samples is significant for assessing their antioxidant activity, which is crucial for understanding their potential health benefits and ability to combat oxidative stress. In addition, the excess consumption of pyrogallol can have significant negative effects on human health. A voltammetric sensor has been developed for the determination of pyrogallol using ARS modified platinum electrode. The electrode was prepared by electrodeposition of alizarin red S on a platinum electrode using cyclic voltammetry with a potential scan range of - 0.4 to 1.2 V against an Ag/AgCl quasi reference electrode for 60 cycles as optimum number of cycles. The modified electrode was characterized by CV and SEM techniques. This modified alizarin red S platinum electrode showed remarkable electrocatalytic performance and stability, resulting in a significant increase in pyrogallol oxidation current by 11.05% compared to the pyrogallol oxidative current at the unmodified platinum electrode. A well-defined oxidation peak was observed at ~ 0.40 V. The sensor exhibited a low limit of detection (LOD) of 0.28 µM and a linear standard curve covering the ranges of 1.0-40 µM and 0.01-10.0 mM pyrogallol. Extensive studies were performed to evaluate possible interferences from various organic and inorganic compounds and yielded satisfactory results that confirm the selectivity of the developed sensor for pyrogallol determination. In addition, the ARS-Pt electrode provided consistently reliable results for the accurate detection of pyrogallol in water and tomato samples.</p>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141174266","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid spectrophotometric determination and extraction of platinum(IV) from pharmaceuticals assisted by 2-(2-(1-(thiophene-2-yl) ethylidene) hydrazinyl) benzoic acid (TEHBA).","authors":"Amruta Murkute, Haribhau Aher, Somnath Bhumkar, Shashikant Kuchekar","doi":"10.1007/s44211-024-00612-9","DOIUrl":"10.1007/s44211-024-00612-9","url":null,"abstract":"<p><p>It has been suggested that the chelating agent 2-(2-(1-thiophene-2-yl) ethylidene) hydrazinyl) benzoic acid (TEHBA) be utilized to extract, separate and measure platinum(IV) by UV-visible spectrophotometry at the microgram level. Following 5 min of heating the reaction mixture in a water bath, Pt(IV)-TEHBA complex formed. This complex was formed in the presence of potassium iodide solution with a molar absorption coefficient 1.9 × 10³ dm³ mol^-1 cm^-1. At 420 nm, the substance exhibited the greatest absorption. As Beer's law described, the Pt(IV)-TEHBA complex for platinum(IV) has a beer's range of 10-50 μg cm^-3. It was determined that the proportion ratio of the Pt(IV)-TEHBA complex was 1:1 after its extraction. Despite the investigation of interference from various ions, it was ascertained that the method exhibited selectivity exclusively towards platinum(IV). The trace amounts of platinum(IV) were extracted and quantified from synthetic mixtures representing alloys, binaries and ternary synthetic mixtures. The process of extracting platinum(IV) from pharmaceutical samples involves the implementation of a specific method. Moreover, the procedure exhibits a progressive segregation of palladium(II), platinum(IV) and nickel(II) while also boasting its ease of operation.</p>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141330312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enhanced synthesis of antibody-functionalized gold nanoparticles for multiplexed exosome detection via mass signal amplification in LDI-TOF MS.","authors":"Gaon Jo, Woon-Seok Yeo","doi":"10.1007/s44211-024-00604-9","DOIUrl":"10.1007/s44211-024-00604-9","url":null,"abstract":"<p><p>We present a novel method for sensitive exosomal protein detection using organic matrix-free laser desorption/ionization time-of-flight mass spectrometry (LDI-TOF MS) and gold nanoparticles (AuNPs) functionalized with mass tags for signal amplification (Am-tags). Target exosomes were captured by specific antibodies on AuNPs and a biochip, where the antibody-presenting AuNPs (Ab/Am-tag@AuNPs) contained excess Am-tags. LDI-TOF MS analysis revealed the mass signal of Am-tags on Ab/Am-tag@AuNPs, indicating the presence of target exosomes. Thus, the target signal was amplified by a large number of Am-tags, resulting in enhanced sensitivity. We optimized the protocol to prepare stable Ab/Am-tag@AuNPs, focusing on parameters such as the concentration and ratio of thiol molecules for AuNP functionalization, suitable solvents for the coupling reaction, and amount of antibodies conjugated to the AuNPs. Subsequently, we evaluated the ability of our method to detect exosomes isolated from three cell lines, NIH3T3, MCF7, and HeLa, using an anti-Rab5 immobilized gold chip and anti-CD63/Am-tag@AuNPs with LDI-TOF MS analysis. Calibration curves constructed for the three cell lines showed a linear relationship with an excellent limit of detection. Finally, we emphasized the versatility of our method for the quantitative detection of exosomal proteins CD63 and mucin 1 (MUC1) using two types of Am-tags. LDI-TOF MS analysis revealed the presence of CD63 and MUC1 at different expression levels in HeLa and MCF7 cancer cells. Our findings clearly indicate the potential of Ab/Am-tag@AuNPs as a sensitive and reliable approach for identifying biomarkers in exosomes, providing valuable insights into their utility in biomedical research and clinical settings.</p>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141080454","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Label-free colorimetric analysis strategies based on adsorption-responsive surface-enhanced photochromic phenomena of tungsten(VI) oxide nanoparticles for amino acids.","authors":"Shohei Tanaka, Kenta Adachi","doi":"10.1007/s44211-024-00607-6","DOIUrl":"10.1007/s44211-024-00607-6","url":null,"abstract":"<p><p>Herein, we present a colorimetric detection method based on the surface-enhanced photochromic phenomenon of tungsten (VI) oxide (WO₃) nanocolloid particles for α-amino acid (AA) molecules, including _L-aspartic acid (Asp), _L-glutamic acid (Glu), _L-histidine (His), _L-isoleucine (Ile), _L-leucine (Leu), _L-lysine (Lys), _L-phenylalanine (Phe), and _L-valine (Val). The UV-induced photochromic phenomena in the AA/WO₃ binary aqueous systems were investigated using UV-Vis absorption spectrometry. The adsorption properties of the AA molecules on the surface of the WO₃ nanocolloid particles have been identified using a combination of adsorption isotherm analysis and attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. A good linear correlation between the concentration of the AAs adsorbed on the surface of the WO₃ nanocolloid particles and the initial photochromic coloration rate in the corresponding UV-irradiated WO₃ colloidal aqueous solution was obtained with over three orders of magnitude, indicating that the surface-enhanced photochromic phenomenon of the WO₃ nanocolloid particle can be used to detect the AA molecules. In addition, based on the results of the UV-Vis absorption, ATR-FTIR, and adsorption isotherm analyses, we have experimentally demonstrated that the AA/WO₃ binary aqueous system with inner-sphere adsorbed Ile, Leu, Lys, or Val molecules on the surface of the WO₃ nanocolloid particles exhibits a more significant surface-enhanced photochromic phenomenon than the system with outer-sphere adsorbed Asp, Glu, His, or Phe molecules. The strong inner-sphere adsorption of the AA molecules successfully improved the limit of detection. This study provides valuable insights into a \"label-free\" colorimetric assay system based on the surface-enhanced photochromic phenomenon of the WO₃ nanocolloid probe.</p>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141247300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}