REVERSED-PHASE HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC DETERMINATION OF CYPROHEPTADINE FROM URINE BY SOLID-PHASE EXTRACTION

A simple, sensitive and reliable high-performance liquid chromatograph ic method for the determination of cyproheptadine in urine by solid-ph ase extraction (SPE) has been developed. The sample matrix was passed through a pre-conditioned C-18 cartridge, washed with methanol-water s olution (4:1) and eluted with methanol. The methanolic solution was ev aporated to dryness, reconstituted with methanol and chromatographed u sing a C,, reversed-phase column. The mobile phase consisted of acetat e buffer (constant ionic strength of 0.005 I)-methanol (56:44, v/v). D etection was performed at 254 nm with the sensitivity set at 0.002 AUF S. Concentrations as low as 50 ng/ml could be quantitatively determine d by an external standard method and the overall recovery was found to be 76.16%, whereas the limit of detection was estimated as 15 ng/ml.