Amperometric urea biosensors based on the entrapment of urease in polypyrrole films |
| |
Authors: | Juliana Coatrini SoaresAndré Brisolari Valquíria da Cruz RodriguesEdgar Aparecido Sanches Débora Gonçalves |
| |
Affiliation: | Instituto de Física de São Carlos, Universidade de São Paulo, Av. Trabalhador São-carlense, 400CP 369, 13560-970 São Carlos, SP, Brazil |
| |
Abstract: | Urease (Urs) was immobilized in electrochemically prepared polypyrrole (PPy) and the resulting films were characterized by cyclic voltammetry, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and ultraviolet visible spectroscopy (UV-VIS). The enzymatic activity of Urs entrapped in the PPy matrix was confirmed by the catalytic conversion of urea into carbon dioxide and ammonia, when urea was detected amperometrically at different concentrations in standard samples and commercial fertilizers. The PPy/Urs biosensors exhibited selectivity, a relatively high efficiency at urea concentrations below 3.0 mmol L−1, and a sensitivity to urea of 2.41 μA cm−2 mmol−1 L. |
| |
Keywords: | Biosensors Conducting polymers Polypyrrole Urea Urease |
本文献已被 ScienceDirect 等数据库收录! |
|