Fig. 9From: Colorimetric detection of Cr3+ based on gold nanoparticles functionalized with 4-mercaptobenzoic acidThe detection of Cr3+ ions in aqueous solution, the concentration of Cr3+ ions was 1 × 10−5 M. Simulated sample no.1, no.2, and no.3 were abbreviated as S1, S2, and S3, respectivelyBack to article page