Glucose Oxidase-Instructed Fluorescence Amplification Strategy for Intracellular Glucose Detection

Abstract

The accurate detection of glucose at cellular level remains a big challenge. In this study, a signal amplification strategy mediated by silver nanocube (AgNC), glucose oxidase (GOx), and silver ion fluorescence probe (denoted as AgNC-GOx/Ag⁺-FP) is proposed for amplified intracellular glucose detection. The AgNC is oxidized into Ag⁺ by H₂O₂ generated from GOx-catalyzed glucose oxidation reaction, and Ag⁺ remarkably enhances the red fluorescence of Ag⁺-FP. Our results show that AgNC-GOx/Ag⁺-FP is highly sensitive and specific to glucose and H₂O₂. Afterward, the feasibility of using AgNC-GOx/Ag⁺-FP to detect intracellular glucose is verified in five different cell lines. In summary, a sensitive and specific fluorescence amplification strategy has been developed for intracellular glucose detection.