DEVELOPMENT OF ELECTROCHEMICAL BIOSENSOR BASED ON LASER-INDUCED GRAPHENE MODIFIED WITH NANOCOMPOSITE OF REDUCED GRAPHENE OXIDE AND BIMETALLIC SILVER-COBALT FOR URIC ACID DETECTION

• Main Author: Rahma Adzkia, Arini
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/73696
• Institution: Institut Teknologi Bandung

The development of sensors for biomarkers regarding disease detection from body fluids has been widely researched. One of the biomarkers that can be found in body fluids is uric acid. Abnormal uric acid levels can indicate diseases such as hyperuricemia, hypouricemia, and arthritis inflammation. Therefore, a uric acid detection method is needed so that monitoring can be carried out regularly. Electrochemical biosensors such as laser-induced graphene (LIG) can be utilized as alternative detection method based on its efficiency and low-cost, making it possible for point-of-care detection. By modifying the electrode surface using nanocomposites such as reduced graphene oxide and silver-cobalt which also known as rGO/AgCo, the sensitivity and selectivity of LIG can be improved for better performance. In this study, the rGO/AgCo nanocomposite was synthesized by the green synthesis method using honey. Based on analysis using SEM-EDX, Raman, UV-Vis, and XRD, the rGO/AgCo nanocomposite was proved to be successfully synthesized. The rGO/AgCo nanocomposite was then modified on the LIG surface. The performance of LIG/rGO/AgCo increased electrochemically, indicating the successful modification of rGO/AgCo on LIG. This increase indicates a synergistic effect of rGO/AgCo with good conductivity and large surface area. Through DPV testing, LIG/rGO/AgCo in this study was found to have good electrochemical behaviour and selectivity for uric acid in the linear range 0.1–2000 ?M with LOD 3.75 ?M, LOQ 11.36 ?M, linearity 0.99128, and a sensitivity of 1.76 ?A.?M?1 .cm?2 . The detection range allows LIG/rGO/AgCo to be used for the detection of uric acid in body fluids, such as sweat, urine, and blood.