Abstract
In this study, we developed graphite screen-printed electrodes (GSPEs) modified with zirconium UiO-66 metal-organic framework (Zr-UiO-66 MOF) for the detection of vanillin (VN) and folic acid (FA). Zr-UiO-66 MOF was synthesized via a solvothermal method and used to modify the GSPEs to enhance the sensor sensitivity. Cyclic voltammetry (CV) was employed to investigate the electrochemical properties of the modified GSPEs in a VN solution. The results demonstrated the successful modification of the GSPEs with Zr-UiO-66 MOF. Significantly, the UiO-66 MOF-modified GSPEs demonstrated the ability to detect VN across a linear dynamic range (LDR) of 0.1 to 238.0 µM, highlighting their potential as electrochemical sensor. The limit of detection (LOD) was calculated to be 0.03 µM, based on a signal-to-noise of 3 (Sb/m = 3.0). The successful development of this electrochemical sensor offers a promising approach for the simultaneous detection of VN and in FA tablets, coffee milk, and urine samples, with recovery values ranging from 90.0% to 110.0% for VN and 97.0% to 104.2% for FA.