铁(Ⅲ)置换氧化还原滴定法测定维生素C片剂及针剂中抗坏血酸  

Fe(Ⅲ) Replacement Redox Titration of L-Ascorbic Acid in Vitamin C Tablets and Injections

作　　者：曾盔[1] 周军[1] 王锦[1] 丁春霞[1] 

机构地区：[1]湖南农业大学理学院应用化学系,长沙410128

出　　处：《理化检验（化学分册）》2007年第7期549-551,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：国家自然科学基金(30540019);湖南省教育厅科研基金(06JC0149)资助

摘　　要：基于将测定抗坏血酸的碘滴定(药典)法和铁铵矾滴定法相结合,即先用铁铵矾基准物氧化碘化钾置换出相当量的I2,再在维生素C药物溶液滴定中让相当量的I2定量氧化抗坏血酸。合适的反应条件是:乙酸介质,碘离子过量,室温置暗处置换反应10 min。将该法用于维生素C药物中抗坏血酸的测定,结果与药典法结果相符。It was proposed that the ascorbic acid in vitamin C （VC） tablets or injections was determined in the following steps; （1） a definite amount of ferric ammonium sulfate （primary standard） was dissolved in dil. HOAc solution, and an excess amount of KI was added, and the solution was kept in derk for 10 min for quantitative liberation of iodine （as I3^- ） ; （2） a definite amount of the sample of VC tablet or injection was dissolved in 200 mL of 0. 1 mol · L^-1 HOAc solution, which was used as titrant to react with the iodine （as I3^- ） liberated in the former step. Consistents results were obtained by this method and the pharmacopoeia method.

关 键 词：维生素C片或针剂 抗坏血酸 硫酸高铁铵 碘量法 药物 

分 类 号：O657.31[理学—分析化学]