A novel selective and sensitive multinanozyme colorimetric method for glutathione detection by using an indamine polymer.

A sensitive and selective novel multinanozyme colorimetric method for glutathione (GSH) detection was developed. MnO ₂ -nanozymes can catalyze the oxidation reaction of 3, 3՛-diaminobenzidine (DAB) and produce a brown indamine polymer. In the presence of GSH, this reaction slowly proceeds. When Au-nanozymes was used as peroxidase mimic along with MnO ₂ -nanozymes, the analytical signal and selectivity (particularly, over Cys and AA) were significantly improved for GSH detection. Therefore, this novel multinanozyme system was further developed through optimization for the colorimetric detection of GSH. The calibration curve presented two wide linear range from 0.05 to 0.19 and 0.19-11.35 mg L ^{̶ 1} with a very low detection limit of 0.02 mg L ^{̶ 1} (5 nM) for GSH. The developed method was employed for human serum analysis without any dilution and any deproteinization.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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