Speaker
Description
Screen-printed electrodes (SPEs) are widely used as biosensing platforms due to their simple and cost-effective fabrication. They are commonly produced on virgin PET or ceramic substrates; however, with increasing concern over plastic waste, alternative sustainable materials are needed. This study investigates the use of recycled polypropylene (R-PP) sourced from discarded mineral water bottles as a substrate for SPE fabrication, offering a low-cost and environmentally responsible approach. Collected PP bottles were cleaned, cut, extruded, and hot-pressed into uniform sheets suitable for electrode printing. SPEs were then fabricated on R-PP, PE, PVC, and PET substrates using screen-printing technique with graphite ink as the working and counter electrodes while Ag/AgCl ink for the reference electrodes. Surface characterization performed using Scanning Electron Microscopy (SEM) and 3D profilometry revealed the morphological and topographical features of each substrate, including roughness, texture, and uniformity which are critical parameters influencing the ink adhesion and electrode stability during the application test. Electrochemical performance was evaluated using current–voltage (I–V) measurements across five concentrations of ferricyanide/ferrocyanide solutions. The results show that substrate materials with polar molecule structures like PET and PVC will perform better as SPE biosensor due to stronger bonding for the adhesion of conductive carbon inks to the substrate surfaces. Even though the performance of SPE made on the R-PP substrate was not really good in the sensitivity test at 5 different concentrations of ferricyanide/ferrocyanide solution, its capability in showing a rising trend in detecting the target when the concentrations were increased is still acceptable. A few solutions will be suggested at the end of this study to improve the performance of R-PP as the potential SPE substrate
