ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Determination of tyrosinase activity with manganese dioxide nanosheet-assisted fluorescence

Qi Zhou, Ting Zhou, Yifeng Tu, and Jilin Yan

The Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, China

E-mail: yanjl@suda.edu.cn

Received: 5 October 2022  Accepted: 11 February 2023

Abstract:

Tyrosinase is an enzyme in the process of melanin formation and relates to the occurrence of freckles, brown spots, or excessive deposition of melanin in human body and other diseases. In this work, a turn-on fluorescence detection toward tyrosinase was developed. Manganese dioxide nanosheets were conveniently synthesized as an oxidizing agent. These nanosheets converted non-fluorescent o-phenylenediamine (OPD) into a fluorescent product. This reaction and the related fluorescence could be inhibited by reductive dopamine. When tyrosinase was introduced, it catalyzed the oxidation of dopamine and thus led to a recovery of the fluorescence. This signaling provided enhanced fluorescence responses toward tyrosinase in the range 0.006–0.08 U/mL, with a detection limit at 0.003 U/mL. The scheme was successfully applied onto practical samples.

Graphical abstract

Keywords: Tyrosinase; Dopamine; o-Phenylenediamine; Oxidation; Fluorescence; Catalysis

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-02729-z

Chemical Papers 77 (7) 3671–3678 (2023)