Validation and application of a stability-indicating HPLC method for the in vitro determination of gastric and intestinal stability of venlafaxine.

Gastrointestinal stability of venlafaxine was evaluated in vitro in simulated gastric (SGF) and intestinal (SIF) fluids using a stability indicating HPLC method. The method was validated using a 5 microm Ascentis C18 column (150 mm x 4.6 mm) and mobile phase consisting of 30% acetonitrile in 20 mM potassium phosphate buffer (pH 6.

Determination of ginsenosides (ginseng saponins) in dry root powder from Panax ginseng, Panax quinquefolius, and selected commercial products by liquid chromatography: interlaboratory study.

Twelve collaborating laboratories assayed 4 products, namely, Panax ginseng, Panax quinquefolius, and 2 ginseng products, for 6 ginsenosides: Rb1, Rb2, Rc, Rd, Re, and Rg1. Collaborators also received a negative control for the recovery study. Pure ginsenosides were provided as reference standards for the liquid chromatography (LC) analysis and the system suitability tests.