STUDIES ON A NEW ACID DYE—TETRAIODOPHENOLSULFONPHTHALEIN FOR THE DETERMINATION OF AMINE DRUGS

Studies on the quantitative method of tetraiodophenolsulfonphthalein(TIPS) extraction for the determination of five amine drugs of different partition are discribed. This reagent has not yet been reported in literature for determination of amines. A series of condition studies, i. e. measuring the absorption spectrum (λ max: 422.5nm), decreasing the blank, selecting the concentration of the reagent (2.2×10^-3mol/L), choosing the pH value of extraction media and determining the mole ratio of TIPS-amine complxes (1:1) are investigated. In the range of 0～20.0μg/ml, the calibration curve is linear and the coefficient of variation is 4%. The sensitivity of 1% absorbance of benethtropine, benactyzine, atropine, diethylaminoethanol and pralidoxime chloride is 0.052μg/ml, 0.055μg/ml, 0.065μg/ml, 0. 26μg/ml, 48.5μg/ml respectively. For less lipophilic amines, i. e. atropine and diethylaminoethanol, the extinction coefficient of TIPS is about 1.5 and 9.2 times higher than those of BCP and BPB respectively.