Urea sensing device using urease-immobilized silk fibroin-based aminated glassy carbon electrode

摘要

Glassy carbon electrode was successfully functionalized by amine groups (NH2) to produce aminated glassy carbon electrode (aminated GCE) through electrooxidation of carbamic acid. The aminated GCE can be effectively used for the urea sensing by detecting oxidation current changes in the decomposition process of urea by urease. Urease-immobilized silk-fibroin structure was used for the immobilization of urease to the aminated GCE. Prepared bioelectrode (Ur/SF/aminated GCE) was used for the urea sensing by using cyclic voltammetry (CV). The fabricated urea sensing system displays a high sensitivity and linear correlation between current and urea concentrations. The silk-fibroin membrane functionalized by urease can be easily exchanged with another membrane generated in the same batch, and thus a urea sensing system of the present invention can be effectively utilized in portable urea sensing devices.