Electrodeposition of Horseradish Peroxidase (HRP) Enzyme on Polythiophenes / Polypyrrole /Polyaniline (PT/ PPY/ PANI) Substrate for Biosensor Application
DOI: https://doi.org/10.55373/mjchem.v25i1.169
Keywords: Electrodeposition; enzyme; polymer conjugate; biosensor
Abstract
Electrodeposition on substrates or monolayers is problematic as there are several factors influencing the process such as growth rate, temperature, humidity, substrate surface cleanliness, solubility, agglomeration and stability of the materials. These factors do not only inhibit the electrodeposition process but also present challenges to researchers. PANI, PPY and PT are conducting polymers that show excellent chemical, thermal and oxidative stability due to their low hydrogen content and aromatic structure. HRP is frequently used in conjugates to detect the presence of a protein target. In this study, Langmuir Blodgett (LB) and the layer by layer (LBL) method were used. PANI, PPY and PT acted as the polymeric support that was deposited on indium tin oxide (ITO) glass; HRP was added later by electrodeposition. The layers were characterized using UV-Visible (UV-Vis) spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), Atomic Force Microscopy (AFM), Variable Pressure Scanning Electron Microscopy (VPSEM) and the Four-Point Probe method. The results displayed the interactions and increased conductivity of each layer of the polymer. In an experiment that spanned 30 days, HRP exhibited decreased resistance at 4 °C compared to 27 °C and 60 °C.