Reversed flow-injection method for estimation of chlorpromazine in pharmaceuticals and urine samples using charge-transfer complexation

F Belal,H Hadi,M Jamal

doi:10.4314/bcse.v33i1.2

Abstract

A simple, automated and sensitive reversed flow-injection analysis (rFIA) method for the determination of chlorpromazine hydrochloride (CLP) in pharmaceutical formulations and human urine samples is described. The automated method is based on the formation of charge-transfer complex between CLP (donor) with new reagent (an acceptor) used for the first time namely, 4,4’-tetramethyl-diaminodiphenylmethane (TDM) in the presence of K2S2O8 as an oxidant. An intense blue-colored product, which gave a maximum absorbance at 604 nm, was formed immediately at room temperature. The various chemical and physical conditions that affected the reaction have been studied. The calibration curve was rectilinear within the concentration range 1-45 µg/mL and the detection and quantification limits of 0.72 and 2.40 µg/mL respectively with a sample through put of 80 sample/hour. The proposed procedure was applied successfully for the estimation of CLP and the results obtained were favorably compared with those given by a reference method, and there was no significant difference between the obtained results, regarding accuracy and precision at the 95% confidence level. KEY WORDS: Chlorpromazine, Flow injection analysis, Charge-transfer complexation Bull. Chem. Soc. Ethiop. 2019, 33(1), 11-20.DOI: https://dx.doi.org/10.4314/bcse.v33i1.2

Highlights

Chlorpromazine hydrochloride is the most important compound in the large group of phenothiazine derivatives
The official methods for its determination listed in the British Pharmacopoeia (BP) and US Pharmacopoeia (USP), consist in the non-aqueous potentiometric titrimetry or spectrophotometry in the ultraviolet region [2, 3]
Several methods were reported for determination of chlorpromazine hydrochloride (CLP) in dosage forms and biological samples, these methods involved spectrophotometric methods using several reagents such as Eriochrome cyanine R [4], Alizarin red S [5], and ferricyanide [6] were reported, but these methods either required a relatively a complexometric extraction steps [4, 5], or long heating time [6]

Summary

Introduction

Chlorpromazine hydrochloride is the most important compound in the large group of phenothiazine derivatives It is widely used as antipsychotropic, anticholinergic, and antihistaminic drug [1]. Several flow injection analysis methods were employed for the determination of chlorpromazine together with spectrophotometry [15, 16], spectrofluorometry [17, 18], and chemiluminescence [19,20,21]. Some of these methods either require expensive or unavailable materials

Methods

Results

Conclusion