COST-EFFECTIVE IMMUNOSENSOR FOR PROTEIN DETECTION USING PCB ELECTRODES AND AD5941 ANALOG IC-BASED IMPEDANCE MEASUREMENTS

Abstract

This paper presents the development of a cost-effective protein immunosensor utilizing a printed circuit board (PCB) platform and AD5941 analog IC-based impedance measurements. The electrode was fabricated using PCB technology and electroless nickel immersion gold (ENIG) techniques, with the surface modified to immobilize bovine serum albumin antibodies (anti-BSA), forming an immunosensor for detecting bovine serum albumin (BSA). Integrated with a compact AD5941 impedance measurement device designed for detecting biomolecular layers, the sensor measured impedance changes associated with biomolecular layer formation during surface modification. Experimental results demonstrated successful BSA capture on the sensor surface, confirmed by fluorescence measurements. Additionally, the immunosensor detected BSA at a 5 µM concentration. The total impedance consistently increased with each electrode surface functionalization step, while the control electrode, which omitted a functionalization step, showed minimal impedance change. These results suggest that the PCB-based immunosensor, combined with the AD5941 measurement device, holds significant potential for biomedical diagnostics.