DOI: 10.36347/sajp

Pages: 370-375

The aim of the present study was to develop and validate a HPLC method for the assay of sildenafil citrate (SIL) in powder preparations prepared from Revatio Tablets 20 mg for infants with persistent pulmonary hypertension of the newborn. The good recovery of SIL from preparations was achieved using a methanol:0.1N HCl =1:1 solution as the extraction solvent. A chromatographic system comprising a YMC AM12S05-1506WT column, mobile phase of CH3CN:H2O:HClO4:NaClO4=400:600:1:5 (V/V/V/W), flow rate of 1 mL/min, and UV detector set at 290 nm showed good chromatographic separation for SIL and the internal standard (propyl 4-hydroxybenzoate). A regression analysis revealed that the method was linear over the standard curve range from 0.01 to 1 mg/tube. Inter-day precision values between the ranges were 4.3% or better. Accuracy values between the ranges were -0.9% - 7.0%, except for the value of 0.01 mg/tube. The accuracy value at 0.01 mg/tube was 16.6%, which indicated that the limit of quantitation of this method was 0.01 mg/tube. We herein demonstrated that this method is useful for determining SIL in a powder preparation prepared from Revatio tablets 20 mg