【摘要】 单质碘熄灭固定于增塑的PVC膜中的芘的荧光,且这种熄灭作用可逆。本文据此研制了用于测定单质碘浓度的荧光敏感膜,最佳膜组成为2～4mg芘、50mgPVC粉、100mg邻苯二甲酸二异辛酯,测定碘的浓度范围为2.26×10^-5～1.04×10^-3mol/L。此膜测定单质碘的重现性好,响应时间小于40s。除Fe³⁺、Bi³⁺外,其它常见离子均无干扰。将此膜用于食盐中碘的测定,结果令人满意。更多还原

【Abstract】 A new fluorescence sensing membrane for the determination of iodine based on reversible fluorescence quenching of pyrene dissolved in plasticized polyvinyl chloride （PVC） has been developed. The optimum membrane consists of 2-4 mg pyrene, 50mg PVC, 100 mg bis（2 -ethylhexyl）phalate. With the optimum sensing membrane described, iodine in sample solutions from 2. 26×10^-5 to 1. 04X10^-3 mol/L can be determined. Besides a high reproducibility of the optical signals,the very short response time of less than 40 s is realized. The membrane has good selectivity, except for Fe3+ and Bi3+, other usual ions in foods do not interfere. The proposed method has been applied to the determination of iodine in table salt with satisfactory results.更多还原