溶剂浮选-间接光度法测定抗坏血酸  

Solvent-Floatation-Indirect Photometric Determination of Ascorbic Acid

作　　者：陈会利[1] 吕鹏飞[1] 闫永胜[1] 

机构地区：[1]江苏大学化学化工学院

出　　处：《理化检验（化学分册）》2007年第6期476-478,481,共4页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

摘　　要：于pH 7.0的磷酸盐缓冲介质中,CTMAB＋及I3-离子间借静电引力形成离子缔合物,可将其浮选入5.0 mL苯中,此缔合物在溶剂中,于365 nm处有吸收峰,较简单的I3^-离子在相同条件下的吸收峰（350 nm）红移了15 nm。在此溶液体系中存在抗坏血酸时使离子缔合物产生褪色反应,且在抗坏血酸浓度在25μg/50 mL以内时与吸光度的降低值（ΔA）间呈线性关系。在抗坏血酸浓度为6.0μg/50 mL时连续测定6次,所得结果的RSD为1.2%,回收率在96%-101%之间。In a phosphate buffer medium of pH 7. 0, an associated compound was formed between CTMAB^＋ and I3^-, which was floated into 5. 0 mL of benzene. The compound CTMAB^＋ -I3^- showed an absorption maxima at 365 nm, with red-shift of 15 nm from the absorption maxima of I3^- （λmax = 350 nm）. Color-fading of the associated compound was observed by the presence of ascorbic acid in the reaction system, and linear relationship between the magnitude of decrease in absorbance （AA） and the concentration of ascorbic acid was found in the range within 6. 0 μg per 50 mL of solution. Test for precision was made at concentration level of 6. 0 μg for 6 determination, RSD found was 1.2%, values of recovery found were in the range 96%-101%.

关 键 词：溶剂浮选 离子缔合物 分光光度法 抗坏血酸 

分 类 号：O657.31[理学—分析化学]