| Summary: | 碩士 === 國立臺北科技大學 === 化學工程研究所 === 100 === Part Ⅰ：The hybrid composites of xanthurenic acid (Xa), flavin adenine dinucleotide (FAD), and carbon nanotubes (CNTs) have been successfully prepared on electrode surface and discussed with different prepared procedures. The polyXa-FAD/f-MWCNT formed with the firstly polyXa and FAD electro-codeposition and the secondly CNTs adsorption shows much higher current response than those hybrid composites made by inverted procedures. It is surface-confined and stable in various scan rates and different pH conditions. Particularly, the polyXa-FAD/f-MWCNT composite shows higher current response and lower over-potential to reduced β-nicotinamide adenine dinucleotide (NADH) and hydrogen peroxide (H2O2). Amperometric response provides a linear response range of 5×10-6–1.7×10-4 M and 1×10-4–2.9×10-3 M with a sensitivity of 155 μA mM−1 cm−2 and 60 μA mM−1 cm−2, and detection limit of 10-6 M and 10-4 M (S/N = 3) for NADH and H2O2, respectively. No interference occurred in the amperograms except of the case for NADH determination in the presence of AA. Linear sweep voltammetry (LSV) technique can help to distinguish NADH and AA response using this bifunctional sensor for NADH and H2O2 determination in the biosystem.
Part II：The simultaneous determination of ascorbic acid (AA), dopamine (DA), and uric acid (UA) is investigated with polymers/carbon nanotubes (CNTs) hybrid composites including xanthurenic acid (Xa), single-walled carbon nanotubes (SWCNT), and multi-walled carbon nanotubes (MWCNT). The functionalized CNTs with acidic treatment can be more hydrophilic to adsorb on electrode surface. The film type of CNTs covered polyXa on electrode surface is found with higher current response and more reversible redox couple in neutral solution. The polyXa/ f-MWCNT of this film type is stable in different scan rates and pH conditions. It shows higher current response and lower over-potential to AA, DA, and UA species when compared with other modifiers including polyXa, polyXa/SWCNT, SWCNT/polyXa, f-MWCNT/polyXa, and polyXa/f-MWCNT. It provides a linear response range of 2×10-4–1×10-3 M, 4×10-5–3.2×10-4 M, and 2×10-4–1×10-3 M with a sensitivity of 86, 5814, and 1429 μA mM−1 cm−2 and detection limit of 10 μM, 1 μM, and 5 μM (S/N = 3) for AA, DA, UA, respectively.
Part III：Herein we report the facile synthesis of poly taurine/zirconia nanoparticles (ZrO2) modified film glassy carbon electrode and its application for the detection of salbutamol and ractopamine. The poly taurine/ZrO2 nanoparticles was directly employed for the detection of salbutamol and ractopamine using linear sweep voltammetry(LSV).The modified film shows a well oxidation peak for salbutamol at 0.71V and ractopamine at 0.65V. Furthermore, the electrochemical measurements and surface morphology were studied using CV, EIS and SEM analysis. The film exhibits rapid and linear electrocatalytic response of salbutamol with the sensitivity of 456.1 μA mM-1 cm-2 and 4889.1 μA mM-1 cm-2 for ractopamine. The proposed electrode also successfully detects the salbutamol and ractopamine in pig meat and human urine samples.
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