A comparative study using HPLC and packed column supercritical fluid chromatography for the assay of three anti-psychotic dosage forms.

A reproducible and selective method was developed for the analysis of three anti-pschycotics, i.e. haloperidol, trifluoperazine and trihexyphenidyl in bulk and dosage forms using packed column supercritical fluid chromatography (SFC). The analytes were resolved by elution with supercritical fluid carbon dioxide doped with 16.67% (v/v) methanol containing 0.8% isopropylamine. Parallel studies were performed by HPLC using ion pairing reagent and a comparison is discussed. The method was successfully used for the assay of three formulations containing a combination of: (1) haloperidol-trihexyphenidyl; (2) haloperidol-trifluoperazine; (3) trifluoperazine-trihexyphenidyl.