EFFECT OF GLUCOSE ELECTRO-OXIDATION REACTION RATE BY ADDITION OF GOLD NANOPARTICLES AND MOF CU-BTC CATALYSTS ON CARBON PASTE ELECTRODES

• Main Author: Kasim, Wandi
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/67117
• Institution: Institut Teknologi Bandung

Carbon-paste electrode can be used for detection of glucose, however, glucose is one of molecules that hard to be oxidized especially by inert electrode like carbon-paste electrode. As a common knowlede, the oxidation of glucose can be helped by adding the catalyst. Rate of oxidation of glucose on electrode interface can be represented by k0 value (or ks in some literatures). The greater the k0, the better the catalyst will perform. To increase k0 several approaches can be used, some of which are using gold nanoparticles, MOF Cu-BTC, and combination of gold nanoparticles and Cu-BTC (AuNP@Cu-BTC). Cu-BTC is one type of MOFs that can be synthesized by reacting Cu(II) ions and trimesic acid (H3BTC). Cu- BTC has been chosen because it has nonpolar linker that can be easily bind to carbon-paste electrode. Cu(II) ions that Cu-BTC has can catalyse glucose electro-oxidation. Gold nanoparticles are expected to be improving the Cu-BTC ability to oxidize glucose and can be seen by increasing of k0 value. Gold nanoparticles can be synthesized by Turkevich method by reducing Au(III) to gold in hot sodium citrate solution. That solution will turn purple or wine that absorbs light with wavelenght ranging between 500 – 600 nm, indicating nanoparticles size to be between 5-100 nm. The solution then can be mixed with Cu-BTC directly when cooled giving AuNP@Cu-BTC which is darker compared by Cu- BTC. Electrodes ability to detect glucose and k0 value of every electrode is determined by cyclic voltammetry method. However, because carbon-paste electrode is not flat electrode, its surface area must be determined by ferro/ferricyanide solution, giving the surface area for every electrode 14.45 mm2, 13.83 mm2, 7.99 mm2, and 11.77 mm2 for carbon-paste electrode (CPE), AuNP@CPE, Cu-BTC/CPE, and AuNP@Cu-BTC/CPE respectively. For electrode characterization for glucose electro-oxidation is conducted in glucose solution with NaOH 0,1 M and using cyclic voltammetry with variable scan rate, every k0 of every electrode has been found to be 2.71x10-7 cm2/s, 4.55x10-5 cm2/s, 9.38x10-5 cm2/s, and 2.29x10-4 cm2/s for CPE, AuNP@CPE, Cu-BTC/CPE, and AuNP@Cu-BTC/CPE respectively with electrode with best sensitivity is AuNP@Cu-BTC/CPE which has sensitivity value of 113.631 ?A/mm.cm2.