Carbon electrode obtained via pyrolysis of plasma-deposited parylene-C for electrochemical immunoassays

In this study, parylene-C films from plasma deposition as well as thermal deposition were pyrolyzed to prepare a carbon electrode for application in electrochemical immunoassays. Plasma deposition could prepare parylene-C in a faster deposition rate and more precise control over the thickness in comparison with the conventional thermal deposition. To analyze the influence of the deposition method, the crystal and electronic structures of the pyrolyzed parylene-C films obtained via both deposition methods were compared using Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and Raman spectroscopy. For application as a carbon electrode in immunoassays, the electrochemical properties of the pyrolyzed carbon films from two both deposition methods were analyzed, including the double layer capacitance (2.10 mu F cm(-2) for plasma deposition and 2.20 mu F cm(-2) for thermal deposition), the apparent electron transfer rate (approximately 1.1 x 10(-3) cm s(-1) for both methods), and the electrochemical window (approximately -1.0 similar to 2.1 V for both methods). Finally, the applicability of the pyrolyzed carbon electrode from parylene-C was demonstrated for the diagnosis of human hepatitis-C using various amperometric methods, such as cyclic voltammetry, chronoamperometry, square-wave voltammetry and differential pulse voltammetry.

Automated summary

In this study, carbon electrodes for electrochemical immunoassays were prepared by pyrolyzing parylene-C films deposited using plasma deposition and thermal deposition methods. The influence of the deposition method on the crystal and electronic structures was analyzed, and the electrochemical properties of the pyrolyzed carbon films were compared. The pyrolyzed carbon electrode from parylene-C showed potential for the diagnosis of human hepatitis-C using various amperometric methods.