Abstract:
A simple, precise and rapid isocratic HPLC-UV method for simultaneous
determination of chlorhexidine (CHD) and its degradation product, para
chloroaniline (pCA) in their pharmaceutical formulations was developed. Simple
isocratic elution was selected, the optimized mobile phase was composed of
methanol and acetate buffer solution at 55: 45 ratio, with flow rate of 1.0 ml/min,
injection volume was 20μl, and the separation was performed using C18 column
(200 × 4.6 mm, 5 μm particle size) at ambient temperature. Both components were
determined at 254nm. Linearity of this method was checked using concentration
range of 20 –160μg/ml for chlorhexidine and 0.3 –1.2μg/ml for p-chloroaniline, the
linearity correlation was (R2 =1), for both components.
The limit of detection was (1.07 and 0.012μg/ml) for chlorhexidine and pchloroaniline
respectively. The limit of quantitation was (3.25 and 0.038μg/ml) for
chlorhexidine and p-chloroaniline respectively. The specificity tests were checked
to find that there was no interference between the excipients used and the active
ingredient and its impurity. The average percentage of accuracy for chlorhexidine
and p-chloroaniline was 99.82 (0.34 RSD) and 100.37 (0.38 RSD), respectively
(Not more than 2.0, USP and ICH acceptable limit). For intraday precision for
80%, 100% and 120%, the RSD for recovery percentage for chlorhexidine and pchloroaniline
was 0.08, 0.09 and 0.18, and 0.04, 0.21 and 0.21, respectively. For
interday precision, was 0.81, 0.24 and 0.95, and 0.24, 0.35 and 0.28, respectively.
(Not more than 2.0 acceptable limit). System suitability parameters at all different
conditions were also found to be within the accepted limit
