中药制剂中绿原酸的电化学敏感测定及其与DNA的相互作用

制备了铂纳米粒子和聚3,4-乙烯二氧噻吩(PEDOT)修饰玻碳电极,并将此电极用于绿原酸的电化学研究。实验结果表明,相比裸电极,绿原酸在此修饰电极上的氧化还原峰电流均有所增加,尤以氧化峰电流增加显著。最佳实验条件下,绿原酸的氧化峰电流与其浓度在0.2~100μmol/L范围内呈良好的线性关系,检出限为0.05μmol/L。相比较已报道的其它方法,此方法线性范围较宽,检出限较低。将此电极用于中药制剂双黄连注射液中绿原酸含量的测定,测得加标回收率为97.7%~102.1%。对绿原酸与DNA的相互作用进行研究,得到它们的结合数为3,结合常数为1.62×103L/mol。相关参数可为绿原酸的药理研究以及相似药物的筛选提供参考与理论指导。

Sensitive Electrochemical Determination of Chlorogenic Acid in Traditional Chinese Medicine Product and Its Interaction with DNA

A modified glassy carbon electrode (GCE) was prepared by electrodeposition of platimum nanoparticles(Pt NPs) and electropolymerization of 3,4-ethoxylenedioxythiophene(EDOT) onto the surface of GCE,and scanning electron microscope was employed to investigate its surface morphology.The result showed that the uniform film of poly-3,4-ethoxylenedioxythiophene (PEDOT) and aggregated Pt NPs adhered to the electrode surface.The electrochemical behaviors of chlorogenic acid (CGA) at different electrodes indicated that this modified electrode could significantly improve the electrochemical redox signal of CGA compared with the bare GCE.The experimental conditions e.g.pH value,scan rate and accumulation time were optimized.Under the optimal conditions,the oxidation peak current of CGA was linear in the concentration range of 0.2-100 μmol/L,with a detection limit of 0.05 μmol/L.The sensor was successfully used to detect CGA in real sample of Shuanghuanglian injection,with spiked recoveries of 97.7％-102.1％.Furthermore,the interaction between CGA and DNA was investigated,and the binding number and the binding constant were calculated to be 3 and 1.62 × 103 L/mol,respectively.The result could provide not only a reference for the pharmacological research of CGA,but also a theoretical guidance for the selection of similar drugs.