八元瓜环-司帕沙星超分子体系的电化学研究

Electrochemical Study of the Cucurbit(n=8) uril-sparfloxacin Supramolecular System

利用电化学方法考察了八元瓜环与司帕沙星的相互作用,测试反应的最佳条件及司帕沙星与八元瓜环体系的分析检测性能。研究表明,在司帕沙星溶液中加入八元瓜环,其还原峰电流显著降低,支持电解质为0.2 mol/L KH2PO4-Na2HPO4（pH6.80）,富集时间90 s,扫描速率200 mV/s.用等摩尔连续变化法测定出八元瓜环与司帕沙星的包结比为2∶1,稳定常数为2.28×10^11（L2.mol-2）.在所选择的实验条件下,体系在司帕沙星浓度为1.0×10-6~8.0×10-6mol/L范围内,峰电流与其浓度具有较好的线性关系。实际样品测量的回收率为98.7%-100.3%.

The interaction of sparfloxacin with eucurbit（ n = 8 ）uril was maily investigated by using cyclic voltam- metry. This paper is aimed at determining the interaction of cucurbit（ n = 8）uril and sparfloxacin by electrochem- istry technique and providing an appropriate method for the content analysis of sparfloxacin. The results indicate that the peak current decreased remarkably after the addition of cucurbit（ n = 8）uril. The system is optimized ex- perimental conditions： using the pH = 6.86, 0.2 mol/L solution of KH2PO4-Na2 HPO4 as supporting electrolyte, quiet time for 90 s, scan rate of 200 mV/s. Using the mole ratio method and job method, the stoiehiometric ratio of the interaction of cucurbit（n =8）uril and sparfloxacin system was determined to be 2： 1, and the interaction stability constant of cucurbit（ n = 8 ） uril and sparfloxacin was calculated to be 2.28 ×10^11（L2.mol-2）. The a- nalysis character was also investigated and the results showed that the system has good linear relationship （ 7 = 0. 9967） in 1.0 ×10^-6 - 8.0 ×10^-6 mol/L concentration range, with the linear equation of y =0. 06684 ＋0. 06323x. And the method of analysis the content of sparfloxaxin was successfully achieved.