(427f) Solubility of Lanosterol in Organic Solvents

Lanosterol is a sterol derivative that plays a key role in the biosynthesis pathway of cholesterol. Recently, it has been found to reverse the formation of cataracts. The physicochemical properties of lanosterol are poorly understood. Pure lanosterol (>95%) was isolated from a raw product (54.6%) by a newly developed c18 reverse-phase high-performance liquid chromatography (HPLC) method. Purity and structure were confirmed by gas chromatography–mass spectrometry (GC-MS).Ultraviolet–visible spectroscopy shows lanosterol has a maximum absorption peak at 213 nm and an extinction coefficient 77000M^-1cm^-1. The fusion enthalpy and melting point determined by differential scanning calorimeter are 38.5kJ∙mol^-1 and 404.25 K, respectively. The solubility of lanosterol was measured in methanol, ethanol, acetonitrile, acetone and ethylene acetate using a static equilibrium set up in the temperature range from 290.6 K to 320.8 K. The solubility of lanosterol increases with the increase of temperature and decreases with increasing the polarity of solvents. The solubility of lanosterol has a minimum of 0.11mol∙L^-1 in acetonitrile at 291.6 K and a maximum of 1.27mol∙L^-1 in ethylene acetate at 320.8 K. Furthermore, the solubility of lanosterol in petrolatum at the same temperature range was extrapolated from a binary mixture of toluene and petrolatum. Single solvent data were fitted by the modified Apelblat equation and UNIFAC was used to fit binary mixture data.