Highly Sensitive Dual-Sensing of Blood Glucose and UV light Enabled by Complexing Biazopyridiniums with Quantum Dots

Abstract

Fluorescent probes are widely used in various fields because of their high sensitivity and easy operation. However, their simultaneous sensing of blood glucose and UV light has not yet been demonstrated. Here, we report one strategy of highly sensitive dual detection of blood glucose and UV light by complexing bisazopyridine borate with carboxylated CdSe/ZnS quantum dots. Owing to the photoinduced electron transfer effect, the electron-withdrawing azopyridinium group quenches the fluorescence of quantum dots. Subsequently, the weak bonding between azopyridinium and quantum dots can be broken by two specific reactions: formation of a borate ester from glucose and a borate group, and cis-trans isomerization of azopyridinium, which contributes to restoring the fluorescence of quantum dots. These enable the complex system to act as a turn-on fluorescent sensor for dual sensing blood glucose and UV light, showing a detection limit of 1.68 μM for blood glucose, and a detection limit of 5.4 mW/cm 2 for UV exhibits. This fluorescent probe is characterized by a fast response, high sensitivity, simple operation, and wide detection range, promising for biosensing and environmental industrial detection applications.