Determination of L-tyrosine based on luminescence quenching of Mn-doped ZnSe quantum dots in enzyme catalysis system.

In this paper, we attempted to develop a novel application of Mn-doped ZnSe quantum dots (Mn: ZnSe d-dots) as probes to detect L-tyrosine (L-Tyr). The bio-conjugates of horseradish peroxidase (HRP)-conjugated Mn: ZnSe d-dots were used in the enzyme catalyzed reaction of L-Tyr with H(2)O(2.) Compared with traditional CdTe QDs, Mn: ZnSe d-dots have better biocompatibility and less negative impact on enzyme catalyzed system. In HRP-conjugated Mn: ZnSe-L-Tyr-H(2)O(2) system, electron transfer occurred between Mn: ZnSe d-dots and HRP. It resulted in the luminescence quenching of the Mn: ZnSe d-dots., which can be used to detect L-Tyr. The coupling of efficient quenching of Mn: ZnSe d-dots photoluminescence (PL) and the effective enzyme-catalysis can afford a simple and sensitive method for L-Tyr detection. The Mn: ZnSe d-dots-enzyme catalyzed system displays great potential in the development of enzyme-based biosensing systems for various analytes.