Reduce Graphene Oxide–Rice Husk Activated Carbon Composite Based Glassy Carbon Electrode for Sensitive Electrochemical Detection of Paracetamol

Introduction: Paracetamol is a common painkiller and fever reducer, but taking too much of this drug can cause serious damage to your liver. Hence, the sensitive detection of paracetamol is very important. Conventional techniques such as UV-Vis and HPLC are effective but involve expensive equipment and time-consuming sample preparation. In order to overcome these limitations, a great deal of attention has been paid to the development of sensitive and inexpensive electrochemical sensors. In this work, a glassy carbon electrode (GCE) was modified with an efficient electrocatalytic composite of reduced graphene oxide and rice husk activated carbon (rGO–RHAC) for the electrochemical detection of paracetamol.

Methods: In this study, rGO-RHAC film was fabricated on a glassy carbon electrode using an electrochemical method. Graphene oxide (GO) was first deposited on GCE and then reduced to rGO, followed by dropcasting RHAC to form the rGO-RHAC film. The resulting rGO_RHAC/GCE sensor was evaluated for paracetamol detection by cyclic voltammetry (CV) in 0.1 M PBS. The sensor’s selectivity was tested against common interfering agents, and its applicability was assessed using real water samples.

Results: CV and EIS techniques in 5mM K₃[Fe(CN)₆] solution confirm the formation of rGO_RHAC composite. The modified sensor exhibited excellent electrocatalytic activity towards paracetamol oxidation, with a detection limit of only 0.51μM with a linear range 1μM to 100μM. The enhanced performance is attributed to the synergistic effect between the high conductivity of rGO and the porous adsorption capability of RHAC.

Conclusions: The rGO-RHAC/GCE sensor provides a low cost, simple and stable platform for the detection of paracetamol. Because of its high sensitivity, selectivity and applicability in real sample analysis, it is a promising candidate for monitoring of paracetamol. Its application in portable paracetamol sensors may be further optimised.