荧光桃红分光光度法测定微量盐酸异丙嗪

Spectrophotometric determination of micro promethazine hydrochlorine with phloxine

在pH1.85的HCl-NaAc缓冲溶液中，荧光桃红与盐酸异丙嗪依靠静电引力和疏水作用力相互作用形成离子缔合物，其组成比为1：2，最大褪色波长537咖，表观摩尔吸光系数ε=4．07×104L·mol-1·cm-1，研究了体系的光谱特征，适宜的反应条件和影响因素，发现体系的吸光度与盐酸异丙嗪的质量浓度在0．04～3．6μg／mL范围内呈良好的线性关系，线性回归方程A=-0．04991—0．1269p（μg／mL），线性相关系数r=0．9998，检出限和RsD分别为0．0177μg／mL和2．2％。本法可用于药物制剂中盐酸异丙嗪含量的快速测定。

A novel and simple spectrophotometric method has been developed for the determination of promethazine hydrochlorine （PTH） with phloxine in a pH 1.85 HCl-NaAc buffer solution. The proposed method is based on the formation of a red colored product from the condensation reaction of PTH and phloxine, which results in the significant changes of absorbency with a maximum absorption at 531 nm. The stoichiometric ratio of the compound is 1：2, and = 4.07 × 104 L.mol- 1. cm- 1. The beer＇ s law is obeyed in the range of 0.04 × 3.6 μg/mL for PTH. Under the best acidity and concentration of dye, the linear regression equation is A = - 0.04991 - 0. 1269p （μg/mL）, with a linear correlation coefficient of 0.9998. The detection limit is 0.0177 μg/mL and RSD is 2.2%. This method has been successfully applied to the determination of PTH in tablets and injections with satisfactory results.