聚对氨基苯磺酸修饰电极的制备及其在电分析化学中的应用

【作者】 陈小印；

【导师】 王宗花；

【作者基本信息】 青岛大学 ， 分析化学， 2010， 硕士

【摘要】 聚氨基苯磺酸由于其良好的环境稳定性、导电性、宽pH范围内的电化学活性,成为人们研究的热点。碳纳米管(CNT)不仅具有良好的导电性、大的比表面积、高度稳定性,而且将其用作电极修饰材料能促进反应的电子转移。本工作以聚对氨基苯磺酸为电极的主要修饰材料,研究了黄酮类药物在聚对氨基苯磺酸修饰电极上的电化学行为、碳纳米管和聚对氨基苯磺酸复合膜修饰电极对尿酸的协同催化作用、以及银掺杂聚对氨基苯磺酸修饰电极的电化学行为。通过电化学聚合法制备了聚对氨基苯磺酸修饰玻碳电极,分别研究了芦丁和槲皮素在该修饰电极上的电化学行为。两者均能在修饰电极上得到有效富集并产生一个灵敏氧化峰,计算了两者在修饰电极上的电化学参数ks和α。π-π键作用使得黄酮类药物在对氨基苯磺酸上吸附富集,产生灵敏的电化学信号。在优化实验条件下,建立了灵敏检测芦丁和槲皮素的电化学方法,成功用于实际样品测定。制备了聚对氨基苯磺酸／碳纳米管复合膜修饰电极,研究了尿酸和抗坏血酸在该修饰电极上的电化学行为。与聚氨基苯磺酸和碳纳米管单层膜修饰电极相比,两者的氧化峰电流显著增加,峰电位差达到337 mV。表明碳纳米管和聚合物产生协同增效作用。碳纳米管和聚合物二聚体发生共轭作用,提高了修饰电极的灵敏度和选择性。以银作为掺杂体,利用循环伏安法制成银掺杂的聚对氨基苯磺酸修饰玻碳电极，研究了该修饰电极的电化学特性及H2O2在电极上的电化学行为。在pH 7.0的PBS中,H2O2产生一灵敏还原峰,表明该修饰电极对H2O2的还原有良好的催化作用。建立了灵敏检测H2O2的电化学方法,方法用于牛奶中H2O2的测定,结果令人满意。更多还原

【Abstract】 Poly(p-aminobenzene sulfonic acid) (PABSA) has attracted increasing attention for its good stability, high conductivity and electroactivity in broad pH band. Carbon nanotube(CNT) has the unique properties like high electrical conductivity, high specific surface area, high stability. It can promote electron transfer as electrode modifies. The electrochemical activity of flavonoids on the poly(p-aminobenzene sulfonic acid) modified electrode, the synergistic catalyst effect of CNT and poly(p-aminobenzene sulfonic acid) to uric acid and the electrochemical behavior of silver doped poly(p-aminobenzene sulfonic acid) modified electrode have been researched in this work.A PABSA modified glassy carbon electrode was fabricated and the electrochemical behavior of rutin and quercetin was investigated at it, respectively. Rutin and quercetin can effectively accumulate and cause a sensitive anodic peak. Flavonoids can be adsorbed to the polymer surface throughπ-πstacking between the aromatic rings and the dimers, causing an increasing signal. The charge transfer coefficient (α) and the electrode reaction rate constant (ks) were calculated. Under optimized conditions, the proposed method has been successfully applied to the determination of compound rutin tablets and quercetin in hydrolysate product of rutin.A PABSA/CNT composite-modified glassy carbon electrode was fabricated, in which the electrochemical behaviors of uric acid (UA) and ascorbic acid (AA) were investigated. In comparison with PABSA and CNT single layer modified electrodes, the composite-modified electrode had superior electrocatalytic activity. A dramatic enhancement of the peak current and a peak to peak separation of 337 mV was observed. The dimers interacted with the CNT byπ-πstacking and the sensitivity and selectivity of the modified electrode was increased. This indicated that the composite possessed the properties of each component with a synergistic effect.A silver doped PABSA modified electrode was prepared by CVs. The electrochemical behavior of H2O2 was studied by it. In a pH 7.0 PBS, a sensitive reductive peak was observed. The method was applied to the determination of H2O2 in milk with satisfactory results.更多还原