Ti基电极上光化学沉积Hg用于吸附溶出伏安法测定磺胺嘧啶

Determination of Sulfadiazine by Adsorptive Stripping Voltammetry Based on Photochemical Deposition of Mercury on Titanium Electrode

该研究发现采用紫外光照射钛电极表面氧化钛层能够光催化还原Hg2+生成Hg微粒,在Ti基电极上光化学沉积Hg比电化学沉积Hg对磺胺嘧啶具有更强的吸附作用,基于光化学沉积Hg/Ti电极建立了一种吸附溶出伏安法测定磺胺嘧啶的方法。详细考察了溶液pH值、吸附富集时间、溶出起始电位、扫描速率等对测定的影响。结果表明,在pH2.0的B-R缓冲溶液中,磺胺嘧啶在0.48V左右处产生1个灵敏的氧化峰,其峰电流与磺胺嘧啶的浓度在1.2×10-8～1×10-6mol/L范围内呈良好的线性关系(r=0.9972),检出限达4.35nmol/L。

It was found that photochemical deposition of Hg occurred at the layer of TiO2 covering the surface of titanium electrode under UV irradiation, the adsorption of sulfadiazine on the photochemieally deposited Hg was stronger than that on the electrochemically deposited Hg, and a method for the determination of sulfadiazine was proposed by the adsorptive stripping vohammetry based on photochemical deposition of Hg on Ti electrode. The affecting factors such as pH, time of adsorption, starting potential of stripping process and scanning rate were studied. Results showed that a sensitive oxidation peak of sulfadiazine was obtained at about 0.48 V in B - R solution of pH 2.0, and the oxidation peak current was linearly proportional with the concentration of sulfadiazine over the range of 1.2 ×10^-8 to 1 ×10^-6 mol/L（r =0. 997 2） with a detection limit of 4.35 nmol/L.