Anti-Prostate Specific Antigen (Anti-PSA) Modified Interdigitated Microelectrode-Based Impedimetric Biosensor for PSA Detection
Sunil K. Arya* and Shekhar Bhansali
Bio-MEMS and Microsystems Laboratory, Department of Electrical Engineering, University of South Florida, 4202 E. Fowler Avenue, ENB 118, Tampa, FL 33620, USA
- *Corresponding Author:
- Sunil K. Arya
E-mail: [email protected]
Received date: 9 June 2011; Accepted date: 23 August 2011; Published date: 24 August 2011
Interdigitated microelectrodes (IDEs) functionalized with a cysteamine (Cys) self-assembled monolayer (SAM) were used to fabricate a sensitive, disposable, impedimetric biosensor for prostate specific antigen (PSA) detection. PSA specific monoclonal antibody (anti-PSA) was covalently immobilized on cysteamine modified gold surface of IDEs, using N-ethyl-N’-(3-dimethylaminopropyl) carbodiimide and N-hydroxysuccinimide (EDC/NHS) chemistry. Bovine serum albumin (BSA) was used as a blocker to prevent nonspecific adsorption on electrode surface. BSA-anti-PSA/Cys/IDE electrodes were exposed to solutions with different PSA concentrations and their response was measured using a label-free electrochemical impedance (EIS) technique. The impedance changes revealed close a correlation with PSA concentrations in the measurement range of 1 pg.mL−1–100 ng.mL−1, with sensitivity of 0.444 mL.g−1.