Electrochemical Detection of Gentamicin Using a Reduced Graphene Oxide-Yttria Oxide (rGO@Y₂O₃) Nanocomposite-Based Biosensor

The control of antibiotic resistance is at an alarming stage, making the detection of antibiotics as utmost importantance. A sono-chemically-synthesized reduced-graphene oxide-yttrium oxide nanocomposite (rGO@Y 2 O 3 NC) was used to develop an effective electrochemical immunosensing platform for gentamicin detection. The rGO@Y 2 O 3 NC was characterized using different techniques, providing insights into its structural and functional properties. The detection was carried out on a carbon screen printed electrode modified with rGO@Y 2 O 3 NC using differential pulse voltammetry technique. The rGO@Y 2 O 3 NC helped to enhance the electrochemical activity and the functional groups present on rGO helped in efficient electrostatic immobilization of the antibody. Protein kinase A triggered the immunologic interaction and hence helped in achieving higher sensitivity. The developed immunosensor exhibited an impressive limit of detection of 0.457 pM, with a wide range of detection from 1 pM to 100 μM with a sensitivity of 7.03 μA pM −1 cm −2 , representing a substantial enhancement over current technologies. Furthermore, the immunosensor demonstrated practical applicability by effective performance in spiked milk and tap water samples. This highlights its potential for real-world applications in monitoring antibiotic use and ensuring water and food quality control according to regulations.