Silver triangular nanoplates as a colorimetric probe for sensing thiols: Characterization in the interaction with structurally related thiols of different functionality

Publication date: June 2019Source: Microchemical Journal, Volume 147Author(s): Aleksei A. Furletov, Vladimir V. Apyari, Alexey V. Garshev, Pavel A. Volkov, Stanislava G. DmitrienkoAbstractSilver triangular nanoplates (AgTNPs) is a promising and still relatively poorly studied colorimetric probe for sensing various organic compounds. In particular, they undergo aggregation in presence of thiols due to strong interaction with SH-group. We performed characterization of label-free AgTNPs as a colorimetric probe in their interaction with thiols of different functionality. Aggregation of AgTNPs upon the action of thiols is manifested by a decrease of AgTNPs surface plasmon resonance (SPR) band and appearance of SPR band of AgTNPs aggregates in a long-wave region of a spectrum (700–800 nm). It can be used for sensitive spectrophotometric determination of thiols. Four thiols differing in their functional groups were tested. Limits of thiol detection in the selected optimal conditions increase in the series cysteamine < 2-mercaptoethanol < cysteine < 3-mercaptopropionic acid and come to 2, 3, 6, and 9 μg L−1, respectively. Selectivity of the method was evaluated by the example of cysteine. It was found that the determination does not interfere with 1000-fold amounts of inorganic ions and 3000-fold amounts of aminoacids. The method was applied to the determination of cysteine in a drug, brewer's yeast and a biologically active food supplement.
Source: Microchemical Journal - Category: Chemistry Source Type: research