Impedimetric Detection of Alpha-Synuclein using Gold Interdigitated Tetraelectrodes: Morphological and Electrical Assessments

Alpha-synuclein is a protein implicated with Parkinson's disease and as a potential biomarker for diagnosis. This study focuses on developing an electrochemical immunosensor using gold interdigitated tetraelectrodes (AuIDTEs) to detect alpha-synuclein. The research involves morphological and electrical assessments to analyze the sensing surface performance in detecting alpha-synuclein interaction with the immobilized antibody. High-power optical microscopy and 3D nano-profiler imaging techniques were used to evaluate electrode fabrication quality and surface modifications. Electrochemical impedance spectroscopy (EIS) using different modes was employed to measure the electrical response across concentrations ranging from 1 attomolar to 1 picomolar of alpha synuclein. The results show distinct impedance profile and the resulting Nyquist and Bode plots confirmed a decrement in charge transfer resistance (Rct) with increasing concentrations. Sensor demonstrates high sensitivity, detecting below 100 aM, with consistent surface morphology and high signal-to-noise ratio. These findings support the viability of AuIDTEs as a highperformance sensing platform for early Parkinson's disease diagnostics.