DOI: https://doi.org/10.55373/mjchem.v28i4.159

Keywords: Oxybenzone. molecularly imprinted polymer, electropolymerization, screen-printed carbon electrode, cyclic voltammetry

Abstract

Oxybenzone (benzophenone-3) is a widely used ultraviolet (UV) filter in sunscreen formulations; however, its release into aquatic environments poses serious risks to marine organisms. Conventional analytical techniques for oxybenzone detection are often costly, time-consuming, and require sophisticated instrumentation, highlighting the need for simple and portable sensing approaches. In this study, an in situ electropolymerized polypyrrole-based molecularly imprinted polymer (e-MIP) was developed on a screen-printed carbon electrode (SPCE) for oxybenzone detection, with a non-imprinted polymer (e-NIP) serving as a control. The electropolymerization process was carried out by cyclic voltammetry (CV) in the presence of oxybenzone as the template molecule, followed by template removal via a leaching process to generate selective recognition cavities. The fabricated e-MIP was characterized using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy, confirming the formation of the polypyrrole matrix and successful imprinting. Optimization studies indicated that optimal e-MIP performance was achieved using three electropolymerization scan cycles and a 10-minute incubation period at pH 7. Under optimal conditions, the e-MIP sensor demonstrated a reliable linear response to oxybenzone concentrations ranging from 5.0 to 25.0 mM. The limit of detection (LOD) and limit of quantification (LOQ) were calculated as 4.80 mM and 14.5 mM, respectively, utilizing the standard error of the regression. The proposed e-MIP demonstrated strong potential as a disposable, portable, and cost-effective sensor for oxybenzone detection.