Electrochemical determination of hydrogen peroxide, dissolved oxygen, hypochlorite, and glucose using poly(Neutral Red)/FAD and Cu/Ni/MWCNT hybrid composite films

• Main Authors: Yu-Cing Lin, 林育青
• Other Authors: 陳生明
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/zdw23u

碩士 === 國立臺北科技大學 === 化學工程研究所 === 99 === Part Ⅰ： An multifunctional electrochemical sensor for determination of hydrogen peroxide, oxygen, and hypochlorite has been developed by the hybrid film of poly(neutral red) and FAD. This hybrid film was prepared by electro-codeposition involving electrostatic interaction between FAD and PNR. It was known for a good material with surface hermetic sealing, pH-dependence, compatiblity, and stability. It can be a multifunctional electrochemical sensor due to good electrocatalytic properties for H2O2, O2, NaClO, KBrO3, KIO3, and NADH. For H2O2 detection, this electrode has a rapid and linear response to H2O2 with a significant sensitivity of 12.3 μA mM-1 cm-2, a linear range of 10－551.7 mM, and a detection limit of 0.1 μM (S/N = 3). For O2 detection, it has a sensitivity of 122.9 μA mM-1 cm-2, a linear range of 2.2－9.4 mg L-1, and a detection limit of 0.1 μM (S/N = 3). Particularly, this electrode has two characteristic potentials can be selected for NaClO detection. At an applied potential of -0.1 V, it has a sensitivity of 8.1 μA mM-1 cm-2, a linear range of 1.5－141.6 mM, and a detection limit of 0.1 μM (S/N = 3). At an applied potential of -0.45 V, it shows a sensitivity of 9.9 μA mM-1 cm-2, a linear range of 1.5－128.8 mM, and a detection limit of 0.1 μM (S/N = 3). It presents excellent stability at 4 °C, with a variation of response current less than 5 % over 30 days. Part Ⅱ：A novel type of nickel and copper nanoparticles-modified multi-walled carbon nanotubes electrode has been successfully fabricated for sensitive nonenzymatic glucose detection. Nickel and copper can be sequentially electro-deposited on the MWCNT-modified electrode to form Ni/Cu/MWCNT electrode by two electrochemical procedures. It was characterized by X-ray diffraction and atomic force microscopy. Electrocatalytic reaction was found with high current response and low over-potential to glucose. Voltammetric response presented 2.5–20 times of electrocatalytic current better than other modified electrodes including Ni/GCE, Cu/GCE, Ni/Cu/GCE, Ni/MWCNT/GCE, Cu/MWCNT/GCE, and Ni/Cu/MWCNT/GCE. Applied potential at +0.575 V, it showed a high sensitivity of 2632.9 μA mM-1 cm-2 to glucose. Linearity was obtained over a concentration range of 0.025–800 μM with a detection limit of 0.025 μM (S/N = 3). The response time is about 1 s with addition of 0.1 mM glucose. It can effectively avoid the interference from the oxidation of common interfering species such as ascorbic acid, dopamine, uric acid, and carbohydrate compounds. Particularly, it also can effectively analyze glucose concentration in human serum samples. It has superior advantages of low over-potential, high sensitivity, excellent selectivity, good stability, fast response, and low cost, promising for the development of nonenzymatic glucose sensors.