Dual Fluorescent Hydrogel Derived from Cross-Linked Chitosan-Salicylaldehyde-Eu(Ⅲ) for Visual Detection of Volatile Amine and Meat Freshness

Abstract

Based on cross-linked chitosan (CS)-salicylaldehyde (SA)-Eu(Ⅲ), a dual fluorescent hydrogel, designated as Eu-SA-CS, was successfully fabricated. The Eu-SA-CS hydrogel exhibited a green fluorescence around 500 nm, whereas a red fluorescence around 600 nm was observed upon exposure to volatile amines such as triethylamine (TEA). There was a good linear relationship between the fluorescence intensity ratio and TEA volume concentration (0-40 μL/L). Furthermore, the hydrogel could be used to indicate the meat freshness by a change in fluorescence color from green (fresh) to red (spoiled). These results revealed that the present Eu-SA-CS hydrogel could serve as a smart green-red fluorescent signal label for real-time monitoring of meat freshness.

Keywords

dual fluorescent hydrogel / volatile amine detection / meat freshness

Funding

Research Foundation from National Innovation Center of Advanced Dyeing & Finishing Technology, China(2022GCJJ10)