Detection of gatifloxacin by a ratiometric fluorescent probe based on Ag+ ion triggered aggregation-induced emission

Abstract

A ratiometric fluorescent probe was developed in the present work, in which the aggregation-induced emission (AIE) behavior of glutathione-stabilized gold nanoclusters (GSH-AuNCs) triggered by silver (Ag⁺) ions was used for the first time for the detection of gatifloxacin (GAT). The GSH-AuNCs fluorescence (FL) intensity was enhanced with the addition of Ag⁺ ions to GSH-AuNCs. The GSH-AuNCs FL intensity increased when the concentration of Ag⁺ ions was increased. The intrinsic FL intensity of GAT was enhanced but the FL intensity of GSH-AuNCs-Ag⁺ was not altered upon adding GAT to GSH-AuNCs-Ag⁺. The ratio of these dual signals was used for GAT sensing. The linear response range shown by this developed probe was from 0.3 μM to 9 μM with a detection limit of 0.13 μM. The application of the probe was carried out in samples of ophthalmic gel by the standard addition method, with recoveries ranging from 100.00–104.28%. Overall, the probe has good sensitivity, selectivity and excellent recoveries in ophthalmic gel samples.