A novel direct-immersion single-drop microextraction combined with digital colorimetry applied to the determination of vanadium in water

TALANTA

卷:224

Article

Nunes, Leane Santos^1,2  Korn, Maria Gracas Andrade¹  Lemos, Valfredo Azevedo^1,2 

[1] Univ Fed Bahia, Programa Posgrad Quim, Campus Univ Ondina, BR-40170280 Salvador, BA, Brazil

[2] Univ Estadual Sudoeste Bahia, Lab Quim Anal LQA, Campus Jequie, BR-45206510 Jequie, BA, Brazil

关键词: Green chemistry;    Ionic liquids;    Water;    Single-drop microextraction;    Digital image colorimetry;    Environmental studies;   

DOI  :  10.1016/j.talanta.2020.121893

来源: Elsevier

【 摘 要 】

In this study, a method based on direct-immersion single-drop microextraction was developed for the determination of vanadium in water. The detection system uses digital images obtained directly from the solvent drop after the sorption of V(V). The extraction solvent used was the ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate ([C6MIM][PF6]). The images were obtained directly from the solvent drop, with the aid of a camera. The digital images were stored, and the RGB (red, green, and blue) data were obtained. The data collected by the red channel were used to construct the analytical curve since it showed higher sensitivity compared with green and blue channels. Under optimized conditions, the method presented an enrichment factor of 50 and a limit of detection of 0.6 mu g L-1 for 3.5 mL sample volume. The limit of quantification and the relative standard deviation (50.0 mu g L-1) obtained were 1.8 mu g L-1 and 4.8%, respectively. Certified reference material (Plankton) was used to assess the accuracy of the method. The simple, fast, efficient, and low-cost procedure was successfully applied to the determination of V(V) in water samples. The proposed method is also following the principles of green chemistry since it uses minimal volumes of samples, reagents, and solvents and yields a small amount of waste.

【 授权许可】

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