Integrated bioanalytical microsystem

A newly developed integrated bio-microsystem that allows for sequence-specific DNA analysis is presented. Micro-fabricated Si/glass-based devices with functionalities of simultaneous polymerase chain reaction (PCR) target amplification and sequence-specific electrochemical (EC) detection have been successfully developed. The microdevice consists of a reaction chamber formed in a silicon substrate, and an EC sensor fabricated onto a glass substrate. Heaters and temperature sensors are patterned on top of the reaction chamber for thermal cycling of PCR. The glass substrate serves not only as a seal for the reaction chamber but also as a platform for the EC detection of the PCR product. Both the amplification of the target DNA sequence and the subsequent EC detection of the PCR product are carried out inside the reaction chamber. Sequence-specific recognition of the target analyte is achieved through hybridization with the probe immobilized onto the working electrode on the glass substrate. Technical challenges of this PCR-EC microdevice and its application to multiplex pathogen identification are elucidated.