Abstract:
A simple, accurate and precise reverse phase high pressure liquid
chromatographic(RP-HPLC) method has been developed for the simultaneous
estimation of Fluoxetine Hydrochloride(Fluo) and Sildenafil Citrate(Sild) in
tablet dosage form by reverse phase C18 column, Hypersil-BDS (250mm x
4.60mm), Particle Size 5μ. The samples were analyzed by using Potassium
dihydrogen phosphate buffer(0.02 M) : Acetonitrile : Triethylamine in the ratio of
55:44:1 v/v ( pH adjusted to 4.0 with 1% v/v Orthophosphoric acid) as a mobile
phase at the flow rate of 1 ml/min in isocratic mode and detection wavelength
230 nm. Both the drugs give sharp peak with high theoretical plate count and low
tailing factor. The retention time for Sildenafil Citrate and Fluoxetine
Hydrochloride was found to be 3.250 min and 4.980 min respectively. The
validation was carried according to ICH guidelines. In linearity curve correlation coefficients for Sildenafil Citrate and Fluoxetine Hydrochloride were found to be
0.9999 and 0.9999 respectively. The percent recovery was 100.13% for Sildenafil
Citrate and 99.78% for Fluoxetine Hydrochloride indicating accuracy and
reliability of method. The limit of detection was 0.21μg/ml and 0.15μg/ml for
Sildenafil Citrate and Fluoxetine Hydrochloride, respectively and the limit of
quantification was 0.64μg/ml and 0.46μg/ml for Sildenafil Citrate and Fluoxetine
Hydrochloride, respectively. Force degradation study was carried out on
combined dosage form as per ICH guideline and it was exposed to acid and base
hydrolysis, oxidative and thermal conditions to apply stress. Proposed methods
were validated as per ICH guidelines for linearity, accuracy, precision and
robustness for estimation of Sildenafil Citrate and Fluoxetine Hydrochloride in
tablet dosage form. Thus the developed and validated stability indicating method
can be used successfully for marketed formulations.
