Abstract
A simple, rapid and sensitive spectroflurometric method has been developed for the determination of trifluoperazine hydrochloride (TFPH), promethazine hydrochloride (PRO), and dimetindene maleate (DIM) in pure and dosage forms. The method was based on the quantitative quenching effect of studied drugs on the native fluorescence of phloxine B due to formation of nonfluorescent ion association complexes between the studied drugs and phloxine B dye in acetate buffer solution (pH4.0) for TFPH or in citrate buffer (pH3.5) for PRO or phthalate buffer (pH4.0) for DIM. The decrease of phloxine B fluorescence was observed at 558 nm after excitation at 471nm. The relationship between quenching fluorescence intensity and concentration of determined drugs were linear in the range of 1.0-10, 0.5-14 and 0.5-10 µg/ml with detection limits of 0.112, 0.109, 0.073 µg/ml and quantitative limits of 0.374, 0.362, 0.243 µg/ml for TFPH, PRO and DIM respectively. The accuracy (average recovery) was ranged between 98.81 and 100.03% and precision (RSD%) is less than 0.90%. The method has been successfully applied for the determination of studied drugs in pharmaceutical formulations with no interferences. The results were in agreement with certified values of pharmaceutical formations and also with standard addition procedure and standard method applied in state company for drugs in dustry and medical appliance, SDI-Samara.
