Laser-induced porous graphene electrodes from polyketimine membranes for paracetamol sensing

The development of cost-effective materials for fabricating electrodes is crucial for drug, pharmaceutical and environmental applications. This paper presents the synthesis and characterization of a novel polyketimine (PKI) membrane obtained by condensing partially of different weight percentages of oxidized polyvinyl alcohol and aminated polyether sulfone. Using the PKI membrane as a scaffold, we introduced laser-induced graphene electrodes (LIGEs) for the efficient electrochemical sensing of paracetamol (PCM), which serves as a model drug. Electrochemical measurements were conducted to assess the physico-chemical properties, including laser-induced porous graphene features, such as the heterogeneous electron transfer (HET) rate and electrochemically active surface area (ECSA). The obtained results demonstrate that the LIGEs exhibit excellent performance in PCM sensing, showing a linear detection range of 50-600 µM with a detection limit (LOD) as low as 14.3 µM and a good selectivity toward uric acid. Furthermore, the functionalization of the electrode surface with AuNPs improved the electrode physico-chemical properties (HET and ECSA) and lowered the detection limit down to 1.1 µM. Consequently, these affordable electrodes hold great potential for analysing other drugs and detecting heavy metal cations in various applications.