Solubilizing properties of new surface-active agents, products of selective oxyethylation of cholic acid. Part I.

Research was conducted into the properties and identity of the products of oxyethylation of cholic acid, which were obtained with the use of a selective catalyst (K4). The 1HNMR method was employed to assess the content of oxyethylated segments and the analytic level of hydrophilic-lipophilic balance (HLB). Surface activity of the products of oxyethylation in water and 0.1 M HCL was examined and cmc and gamma(25)cmc were determined. These were employed to calculate the thermodynamic potential for micelle formation deltaG(o)m and the surface occupied by the lipophilic structure of the surfactant at the phase boundary. Basic viscosity and hydrodynamic values were determined for the solubilizers and their micellar adducts with diclofenac, ketoprofen, fenofibrate, gemfibrozil and nifedipine. In addition, the amount of solubilized therapeutic agents c/s/ was examined by means of the spectroscopic method and the H/L balance in a solid state. The results obtained in the course of research served as a basis for determining the solubilization mechanism and the stability of the micellar adduct for the purpose of application.