三价铬和烟酸的示波行为及其应用  

OSCILLOGRAPHIC BEHAVIOR OF Cr^(3+) AND NICOTINIC ACID AND THEIR APPLICATIONS

作　　者：郑建斌[1] 倪宏刚[1] 

机构地区：[1]西北大学分析科学研究所陕西省电分析化学重点实验室,西安710069

出　　处：《理化检验（化学分册）》2005年第7期467-469,472,共4页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：国家自然科学基金资助项目(20275030);教育部科学技术研究重点项目(0287);陕西省自然科学基金项目(2004B20)

摘　　要：在0.2mol.L-1NaOH底液中,Cr3+能在二次微分简易示波伏安图阴极支-0.75V(vs.SCE)处产生一个灵敏的峰,该峰高随烟酸-Cr3+配合物量的增加而降低。在pH9.3的NH3-NH4Cl缓冲溶液中,烟酸在二次微分简易示波伏安图阴极支-0.5V处也能产生一个灵敏的峰,该峰高随Cr3+加入量的增加而降低,可用于对Cr3+的间接示波测定。根据Cr3+、烟酸以及Cr3+与烟酸配合物的示波特性,分别建立了用二次微分简易示波伏安法间接测定烟酸或Cr3+含量的新方法,并将其用于烟酸片中烟酸含量的测定。与其他方法相比,此法仪器简单,方法简便快速,无需通氮除氧。In a 0.2 mol·L^(-1) NaOH solution, Cr^(3+) showed a sensitive peak at -0.75 V(vs.SCE) at cathode branch of the 2nd differential simple oscillo-voltammogram, and the peak height decreases with the increase of chelated complex of nicotinic acid and Cr^(3+). In pH 9.3 NH_3-NH_4Cl buffer solution, nicotinic acid produced a sensitive peak at -0.5 V at the cathode branch of the 2nd differential simple oscillo-voltammogram, and the peak height decreases with the increase of concentration of Cr^(3+). Based on the above characteristics of Cr^(3+), nicotinic acid and their complex, two new methods for determination of Cr^(3+) or nicotinic acid are established respectively, and the content of nicotinic acid in tablet was determined. As compared with other common methods, oscillographic determination is a more convenient method due to its cheap equipment and rapid measurement.

关 键 词：示波分析 药物分析 CR^3+ 烟酸 

分 类 号：O657.14[理学—分析化学]