[Determination of apparent aqueous solubility and apparent oil-water partition coefficients of three bufadienolides composition].

To investigate apparent aqueous solubility and apparent oil-water partition coefficients of three bufadienolides composition.A high performance liquid chromatography method was established to determine apparent aqueous solubility of three bufadienolides composition; apparent oil-water partition coefficients of three bufadienolides composition was determined by shaking flask method.The solubility of three bufadienolides composition reached the top value, 76.29 microg x mL(-1) (RBG), 51.85 microg x mL(-1) (CBG), 32.76 microg x mL(-1) (BL) respectively and a total of 160.9 microg x mL(-1) in the condition of 37 degrees C and pH 7.0, therefore three bufadienolides composition can be defined as insoluble products. The solubility of the three decreased in weak acid or base environment to some extent. RBG, CBG, BL are liposoluble components and the sequence of log P is RBG > BL > CBG.RBG, CBG, BL is water-insoluble and hydrophobic. Surfactants can be applied to increase the solubility of three bufadienolides composition.