A Micro Amperometric Immunosensor Based on MEMS

摘要

A micro amperometric immunosensor with the sensitive area of only 1 mm~2 was fabricated on silicon using the technique of Micro-Electro-Mechanical Systems (MEMS). A double exposure of SU-8 photoresist process was developed to create both the sensitive pool and reaction pool. Antibody was immobilized via cross-linking with glutaraldehyde on the sensitive area of the electrode surface, which was electropolymerized with polypyrrole previously. The immunosensor was characterized by detection of human immunoglobulin G (HIgG). The immunosensor displayed a good linear response to HIgG concentrations between 5 ng/ml and 255 ng/ml and demonstrated a fast response time of 3 minutes.