Abstract:
This thesis presents fabrication of screen printed carbon electrodes for nitric oxide detection. Carbon electrodes and gold-coated carbon electrodes were fabricated. The electrode surfaces were modified with tetrasulfonted nickel phthalocyanine (NiTSPc) and nafion to improve sensitivity and selectivity for nitric oxide detection. To evaluate the performance of these electrodes, in vitro experiments using amperometric measurement method at 0.7 V with 10-7 to 10-3 M sodium nitroprusside (SNP) standard solution were performed. The results showed that the electrodes would respond to SNP only when cystaemine was added to the solution. In addition, the results indicated that the gold-coated carbon electrodes modified with NiTSPc offers the best response to SNP (coefficient of determination at 0.94). Moreover, the electrode modified with nafion could reduce the interference substance such as sodium nitrite for 30%. However, the sensitivity to SNP of the electrodes also decreased. Finally, the electrodes were tested in vivo. These included carbon electrodes, gold-coated carbon electrodes, carbon electrodes modified with NiTSPc, and gold-coated carbon electrodes modified with NiTSPc. All of these electrodes were coated with nafion. The experiments were conducted both in normal rats and experimental diabetic rats (DM). The experiments showed that gold-coated carbon electrode modified with nafion is the best in vivo nitric oxide detector for both groups.