Label-free colorimetric analysis strategies based on adsorption-responsive surface-enhanced photochromic phenomena of tungsten(VI) oxide nanoparticles for amino acids
{"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":null,"url":null,"abstract":"<div><p>Herein, we present a colorimetric detection method based on the surface-enhanced photochromic phenomenon of tungsten (VI) oxide (WO<sub>3</sub>) nanocolloid particles for α-amino acid (AA) molecules, including <sub>L</sub>-aspartic acid (Asp), <sub>L</sub>-glutamic acid (Glu), <sub>L</sub>-histidine (His), <sub>L</sub>-isoleucine (Ile), <sub>L</sub>-leucine (Leu), <sub>L</sub>-lysine (Lys), <sub>L</sub>-phenylalanine (Phe), and <sub>L</sub>-valine (Val). The UV-induced photochromic phenomena in the AA/WO<sub>3</sub> binary aqueous systems were investigated using UV–Vis absorption spectrometry. The adsorption properties of the AA molecules on the surface of the WO<sub>3</sub> 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 WO<sub>3</sub> nanocolloid particles and the initial photochromic coloration rate in the corresponding UV-irradiated WO<sub>3</sub> colloidal aqueous solution was obtained with over three orders of magnitude, indicating that the surface-enhanced photochromic phenomenon of the WO<sub>3</sub> 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/WO<sub>3</sub> binary aqueous system with inner-sphere adsorbed Ile, Leu, Lys, or Val molecules on the surface of the WO<sub>3</sub> 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 WO<sub>3</sub> nanocolloid probe.</p><h3>Graphical abstract</h3>\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":7802,"journal":{"name":"Analytical Sciences","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Analytical Sciences","FirstCategoryId":"92","ListUrlMain":"https://link.springer.com/article/10.1007/s44211-024-00607-6","RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0
Abstract
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.
期刊介绍：
Analytical Sciences is an international journal published monthly by The Japan Society for Analytical Chemistry. The journal publishes papers on all aspects of the theory and practice of analytical sciences, including fundamental and applied, inorganic and organic, wet chemical and instrumental methods.
This publication is supported in part by the Grant-in-Aid for Publication of Scientific Research Result of the Japanese Ministry of Education, Culture, Sports, Science and Technology.
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号
