摘要
在磷酸介质中,IO_3^-氧化I^-离子形成I_3^-络阴离子,I_3^-络阴离子进一步与吖啶红(AR)阳离子形成离子缔合物,在聚乙烯醇存在下,溶液清亮。以试剂空白参比,波峰λ_(max)位于584nm处,吸光度A与IO_3^-的浓度成正比。表观摩尔吸收系数ε=5．27×10~5L/mol·cm,IO_3^-含量为0～7．0μg/25ml时服从比尔定律。方法用于碘盐和生物样品检测,结果令人满意。
A highly sensitive spectrophotometric method was developed for the determination of trace amounts of Iodine based on the oxidation of I^- to I3^- by IO3^-and the further reaction of I3^-with acridine red to form the ion-association complex [AO] [L]in dilute phosphoric acid solution. In the presence of polyvinyl alcohol the solution is transparent. The λmax of the absorption spectrum is 584 nm against reagent blank. It was discovered that the absolute value of the λmax is proportional to the IO3^-concentration. The molar absorptivity is ε =5.27 × 10^5 L/mol · cm for normal assay at 584nm. Beer＇s law is obeyed in the range of 0-7.0μ g/25ml. The method has been applied to the determination of iodine in biological samples with satisfactory results.
出处
《食品科学》
EI
CAS
CSCD
北大核心
2007年第4期283-284,共2页
Food Science
关键词
碘
吖啶红
离子缔合物
分光光度法
iodine
acridine red
ion-association
spectrophotometry
