Thanaporn Seesuan, Nutthaya Butwong, Supalax Srijaranai and Siriboon Mukdasai
{"title":"A simple colorimetric sensor based on a new deep eutectic solvent for the detection of chromium†","authors":"Thanaporn Seesuan, Nutthaya Butwong, Supalax Srijaranai and Siriboon Mukdasai","doi":"10.1039/D5RA02492G","DOIUrl":null,"url":null,"abstract":"<p >A selective and sensitive method was developed for the detection of Cr<small><sup>6+</sup></small>. This method was based on a combination of colorimetry and liquid–liquid extraction using a new deep eutectic solvent (DES). A DES/EDTA (ethylenediaminetetraacetic acid) colorimetric probe was prepared using tetrabutylammonium bromide (TBABr) as a hydrogen-bond acceptor, ascorbic acid (AA) as a hydrogen-bond donor, and EDTA as a chelating agent. Following the reduction of Cr<small><sup>6+</sup></small> to Cr<small><sup>3+</sup></small> by AA present in the DES/EDTA probe, a purple complex was formed with EDTA, which was immediately extracted into the DES phase. The enriched complex was subsequently quantified by performing absorbance measurements at 550 nm using an ultraviolet-visible spectrophotometer and a smartphone equipped with ImageJ software to detect the color intensity. Under the optimized conditions, the limit of detection was determined to be 0.056 μM (2.08 μg L<small><sup>−1</sup></small>) and the linear range was 0.5–100 μM with a correlation coefficient of 0.9962. In addition, the intra- and inter-day relative standard deviations were <6%. Notably, this simple and affordable colorimetric sensor was successfully employed in the detection of chromium in water and soil samples with satisfactory outcomes. The developed approach could therefore be highly useful for the determination of chromium in other environmental and biological samples.</p>","PeriodicalId":102,"journal":{"name":"RSC Advances","volume":" 28","pages":" 22641-22648"},"PeriodicalIF":4.6000,"publicationDate":"2025-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/ra/d5ra02492g?page=search","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"RSC Advances","FirstCategoryId":"92","ListUrlMain":"https://pubs.rsc.org/en/content/articlelanding/2025/ra/d5ra02492g","RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
A selective and sensitive method was developed for the detection of Cr6+. This method was based on a combination of colorimetry and liquid–liquid extraction using a new deep eutectic solvent (DES). A DES/EDTA (ethylenediaminetetraacetic acid) colorimetric probe was prepared using tetrabutylammonium bromide (TBABr) as a hydrogen-bond acceptor, ascorbic acid (AA) as a hydrogen-bond donor, and EDTA as a chelating agent. Following the reduction of Cr6+ to Cr3+ by AA present in the DES/EDTA probe, a purple complex was formed with EDTA, which was immediately extracted into the DES phase. The enriched complex was subsequently quantified by performing absorbance measurements at 550 nm using an ultraviolet-visible spectrophotometer and a smartphone equipped with ImageJ software to detect the color intensity. Under the optimized conditions, the limit of detection was determined to be 0.056 μM (2.08 μg L−1) and the linear range was 0.5–100 μM with a correlation coefficient of 0.9962. In addition, the intra- and inter-day relative standard deviations were <6%. Notably, this simple and affordable colorimetric sensor was successfully employed in the detection of chromium in water and soil samples with satisfactory outcomes. The developed approach could therefore be highly useful for the determination of chromium in other environmental and biological samples.
期刊介绍:
An international, peer-reviewed journal covering all of the chemical sciences, including multidisciplinary and emerging areas. RSC Advances is a gold open access journal allowing researchers free access to research articles, and offering an affordable open access publishing option for authors around the world.