Voltammetric Responses of On-Chip Glucose Oxidase Immobilized Diamond-Like Carbon Electrodes

This work reports the fabrication and electrochemical characterization of the polydimethylsiloxane (PDMS) microfluidic three-electrode cell chip utilizing diamond-like carbon (DLC) films as a working electrode for amperometric biosensing applications. The DLC films are prepared by a radio-frequency plasma enhanced chemical vapor deposition (RF-PECVD) technique with CH4 as a carbon precursor gas. Raman spectroscopy is employed to characterize the film structures. Cyclic voltammetry is used to investigate the responses of a standard redox species (K3Fe(CN)6 in KNO3) at the three-electrode system. Immobilization of glucose oxidase at the DLC surfaces is attempt through a covalent linkage. Preliminary results indicate that a mediator-free amperometric detection of glucose can be achieved with this device.