Advances in Bioelectrode Design for Developing Electrochemical Biosensors.

The critical performance factors such as selectivity, sensitivity, operational and storage stability, and response time of electrochemical biosensors are governed mainly by the function of their key component, the bioelectrode. Suitable design and fabrication strategies of the bioelectrode interface are essential for realizing the requisite performance of the biosensors for their practical utility. A multifaceted attempt to achieve this goal is visible from the vast literature exploring effective strategies for preparing, immobilizing, and stabilizing biorecognition elements on the electrode surface and efficient transduction of biochemical signals into electrical ones (i.

Evaluation of diffusion coefficient of thiocholine in enzyme-loaded polypyrrole composite film through different methods and electrode polarization.

In this work, the diffusion of thiocholine ion into an enzyme-loaded polypyrrole film was evaluated by different methods, and the results were compared to identify the most suitable method. The enzyme-loaded polypyrrole film was coated with a thin layer of gelatin and gluteraldehyde so as to prevent enzyme leaching. Diffusion coefficients under normal and prepolarized conditions were calculated by five different methods, namely, the Cottrell method, the method of Peerce and Bard, the theoretical impedance model, the electrochemically stimulated conformational relaxation (ESCR) method, and the direct impedance measurement method.