Facile preparation of a Pt-ERGO composite modified screen-printed electrode for the sensitive determination of...

The mass production of screen-printed electrochemical devices with integrated electrodes has facilitated the widespread adoption of electroanalytical methods. The SPEs (screen-printed electrodes) overcome some obstacles associated with the use of conventional electrochemical cells, making them accessible to untrained operators. Despite their advantages, SPEs require activation/modification of the working electrode (WE) to enhance sensitivity. Nanomaterials, with metal nanoparticles (NPs) dispersed in polymers and/or carbon NPs has gaining popularity for this purpose. In this study, we describe a modification of carbon SPEs (SPCEs) using Pt NPs and reduced graphene oxide (ERGO). The Pt-ERGO@SPCE is prepared by galvanostatic reduction of drop-casted precursors directly onto the WE surface, eliminating complex synthetic steps and high temperatures. After optimizing Pt amount and reduction extent, the modified SPCEs were tested for detecting hydroquinone (HQ) and bisphenol A (BPA). DPV results show significantly increased sensitivity for the quantification of both compounds. The modified SPCEs demonstrates promising performance: precision (5 % HQ, 8 % BPA), detection limits (1.4 μM HQ, 4.6 μM BPA), sensitivity (1688 μA mM^-1 HQ, 441 μA mM^-1 BPA), and recoveries (98-113 % HQ, 98-104 % BPA). This simple electrode modification holds great potential, allowing the preparation of the sensor by personnel who may lack access to well-equipped laboratories, particularly in developing countries.