Stability - Indicating assay for haloperidol syrup by high-performance liquid chromatography

A Snyder selectivity triangle was approved for the optimization of a revers ed-phases HPLC separation of haloperidol, methylparaben and propylparaben i n the presence of their degradation products. The degradation products cons idered were: 4-(4-chlorophenyl)-4-hydroxypiperidine and 4-fluorobenzoic aci d presumed to be hydrolytic products of haloperidol, and 4-hydroxybenzoic p resumed to be a hydrolytic product of parabens. Separation was achieved on an octadecyl silica column using a mobile phase of methanol, phosphate buffer (pH 2.0) and triethylamine (50:50:0.2) with U V detection at 254 nm. The pro posed method was verified for linearity, spe cificity accuracy and reproducibility. The stability-indicating capability of the assay was proved by conducting f orced degradation conditions of light and temperature on a commercial drug product, for the stability investigation of the active ingredient and prese rvatives. It was successfully used to proceed the degradation kinetics of t he drug under several storage conditions.