Yellow emission N-doped fluorescent carbon dots as fluorescent nanoprobes for the detection of L-threonine in real samples

Abstract

L-Threonine, a methylamino acid with side chains forming hydrogen bonds and nonpolar interactions, is an important amino acid in cosmetics, foods, and veterinary drugs. However, up to now, there are few studies on the fluorescence detection of L-threonine. In this work, a fluorescent sensing platform with yellow emission fluorescent carbon dots (CDs) as signal transmission probes is synthesized by a simple, convenient and environmentally friendly one-pot hydrothermal method, and a fluorescence resonance energy transfer donor/acceptor pair is constructed to detect the L-threonine content in the sample with high selectivity and sensitivity in the range of 0.1–0.5 mM, and the detection limit is 6.15 μM. In addition, CDs exhibit good photostability and photoluminescence properties under different salt solutions, pH values and time conditions, and are successfully used for the detection of L-threonine in real samples.