A Turn-on Fluorescent Probe Based on Quantum Dots for Detection of Trace Glutamate Dehydrogenase

Abstract

Abstract We reported a simple and fast fluorescence system based on quantum dots (QDs) to detect glutamate dehydrogenase (GLDH), which inverted glutamate to α -ketoglutarate using nicotinamide adenine dinucleotide (NAD + ) as a cofactor. The fluorescence of CdTe QDs was quenched by NAD + through an electron transfer pathway, and the quencher could be consumed by adding NAD + -dependent enzymes such as GLDH. In the NAD + /GLDH system, the fluorescence of QDs was first quenched by NAD + , and the restored fluorescence was in proportional to the amount of GLDH added. Based on this principle, we designed a fluorescence detection system to detect the concentration of GLDH ranging from 10 U L −1 to 1000 U L −1 , which is a critical concentration range in clinical diagnosis of different kinds of liver diseases.