detection of corticosteroid compounds and phosphodiester- ase inhibitors (pdh-5) as counterfeit in herbal products available in iranian market by hplc method

weight-gain and potency enhancing drugs are the most popular herbal products in iran which are easily available via the internet and through illegal markets. the content of some of these popularly purchased products were investigated for the presence of illegal substance like phosphodiesterase inhibitors (pdh-5) and corticosteroids by hplc method. for this study, ten samples of both kind of herbal medicine were obtained from iranian markets, then chromatographic analysis of corticosteroids was achieved isocratically on a c18 column (c18, 5μm , 150 mm x 4.6 mm) by utilizing a mobile phase of methanol/water (55:45, v/v, ph 7.0) at a flow rate of 1.5 ml/min with uv detection at 250 nm, while analysis of phosphodiesterase inhibitors followed by a c18 column (c18, 5μm,150 mm x4.6 mm) using a mobile phase of methanol/water (65:35 v/v, diethyl amine(100µl/l, ph 3.5) at a flow rate of 1.5 ml/min. uv detector operated at 290 nm. after quantitative analysis, different contents of sildenafil and tadalafil in 3 cases of enhancing herbal remedies and dexamethazone in 3cases of weight gaining herbal medicine have been identified.