Electrochemical Immunosensor with Enhanced Electrocatalytic Activity Using Au-Pt Alloy and f-MWCNT

نویسندگان

1 The NorthCap University, Applied Science Department, Gurugram, Haryana, India, 122017

2 The NorthCap University, Applied Science Department, Gurugram, Haryana, India, 122017

doi
10.22036/abcr.2025.494937.2252
چکیده

Thin films of f-MWCNT (functionalised multiwalled carbon nanotubes) were formed on surface of Indium-Tin-Oxide (ITO) electrode of size 1x2 cm2 by pouring 10 µl of prepared solution of f-MWCNT (1mg/ml). After drying the electrode, optimised gold-platinum alloy nanoparticles (Au3Pt1NP) were electrochemically deposited on the surface of modified ITO electrode under the optimised deposition conditions for solution and number of deposition cycles [1–5]. Deposition of layers of f-MWCNT and Au3Pt1NP (alloy nanoparticles of gold and platinum in 3:1 ratio) on ITO surface were confirmed by Field Emission Scanning Electron Microscopy (FESEM), Energy Dispersive X-ray Analysis (EDAX) and X-ray diffraction (XRD) techniques while to investigate the electrochemical properties, electrochemical methods (cyclic voltammetry (CV), differential pulse voltammetry (DPV) and Electrochemical Impedance Spectroscopy (EIS) were used which indicated improved electrochemical performance of f-MWCNT/ITO electrode. This electrode was further modified with Serum Amyloid A protein (SAA) specific antibodies immobilisation (SAA-Ab/f-MWCNT/ITO) and used to detect protein biomarker Serum Amyloid A (APO-SAA). Electrochemical sensing studies by prepared immunoelectrode confirmed detection in a linearity range of 10 fg/ml to 108 fg/ml. By using equation 3σ/sensitivity, Limit of detection (LOD) was found to be 8.78 fg/ml. Excellent selectivity of fabricated immunoelectrode for SAA biomarker, its stability up to five weeks with 89.18% of current retention and reproducibility studies with relative standard deviation of 3.95% indicates the successful fabrication of immunosensor that can be used to detect SAA biomarker.