Simple and rapid detection of tyrosinase activity with the adjustable light scattering properties of CoOOH nanoflakes.

Abstract

Tyrosinase (TYR), as an important biological enzyme, has been widely used in synthetic biology, medical hairdressing, environmental detection, biological sensors, and other fields. In clinical practice, tyrosinase activity is an important indicator for detecting melanoma. Therefore, the detection of tyrosinase activity is of great importance. Based on the polyphenol oxidase activity of tyrosinase, a simple and rapid detection method was proposed based on the adjustable light scattering properties of cobalt hydroxyl oxide nanoflakes (CoOOH NFs). It was found that the amount and size of CoOOH NFs decreased due to the redox reaction mediated by catechol (CC), resulting in a lower light scattering signal of CoOOH NFs. However, in the presence of tyrosinase, catechol was oxidized to a quinone structure, resulting in the reduced decomposition of CoOOH NFs and recovered light scattering signal, which was developed for the quantitative detection of tyrosinase activity. It was found that in the range of 10-400 U/L, the light scattering intensity wascorrelated linearly with tyrosinase activity, and the limit of detection was 6.71 U/L (3σ/k). To verify the feasibility of the proposed method in clinical samples, thespiked recovery experiments were carried out with human serum samples, which showed recovery rates between 93.0% and 104.6%, suggesting the high accuracy. The proposed assay provides a simple and rapid method for detection of a natural enzyme based on the adjustable light scattering properties of CoOOH nanoflakes, which lays the foundation for the development of various enzyme sensing applications in the future.