In situ formation of silver nanoparticles via hydride generation: A miniaturized/portable visual colorimetric system for arsenic detection in environmental water samples

Abstract

A miniaturized/portable visual colorimetric system based on hydride generation headspace solid phase extraction (HG-HS-SPE) was proposed for arsenic detection by naked eyes. As(III) was transformed into AsH₃via hydride generation process, the volatile AsH₃ was introduced into reaction bottle and reacted with AgNO₃ subsequently. Silver nanoparticles (Ag NPs) were generated in situ, resulting in the color changed from white to black, it could be readout by naked eyes or a smartphone application (color extraction, for RGB readout). The interferences from 9 common ions and 10 conventional hydride generation elements were discussed, the results demonstrated that the proposed method exhibit a good anti-interference. The proposed visual colorimetric method was further applied to seven water samples and their spiked samples, and a certified reference water sample (GBW08605) for demonstrating its accuracy and applicability.

Keywords: Arsenic; Headspace solid phase extraction; Hydride generation; Miniaturized/portable; Silver nanoparticles; Visual colorimetric.