Spectrophotometric Determination of Chlorpromazine -HCI by Ion -Pair Complex Formation with Acid Dyes

Abstract

A simple, rapid, accurate and sensitive spectrophotometric method is  proposed  for  the  detennination  of chlorprQm<tZine -HCl  in  pwe form  and  in pharmaceutical  formulation. This method is based on the formation.  of ion  assodation complexes  of  dmg   with either  thymol

blue or  bromophenol  blue  in an acidic buffer at pH  values 4.17  and

3.68, respectively.

The ion-pair  complexes  formed exhibit absorption maxima  at 41 Onm for  both  thymol   blue and  bromophenol  blue.  These  complexes· are quantitatively extracted   with chloroform.  The  calibration  graphs  are tmear and obeyed  Bee 's law in a cort.ce n:at_ion range of 50-450fg!ml and   H:}-120)lg/ml  w1th  molar   absorptttvttes  of   L0374xl0    and

1.7613xl03   Lmorcm·1    for  thymol   blue   ,and   bromophenol   blue,

respectively.

Statistical  treatment  of  the  experimental  results   indicated  that  the method   is  precise,  accurate   and   the   procedure    was   successfully applied  to the determination of the bulk drug and its pharrnaceutic;al fpnnulations.