Complexation of Bile Acids with ${\beta}-Cyclodextrin$

담즙산류과 베타-사이클로덱스트린간의 복합체 형성

From phase solubility studies bile acids and bile salts were found to form stable inclusion complexes with ${\beta}-cyclodextrin$ in aqueous solution. Stability constant of bile acids were larger than that of bile salts. Phase solubility diagrams of most bile acids showed Higuchi's $A_I$ type but lithocholic acid showed $B_S$ type. Not only the solubility of bile acids but also that of ${\beta}-cyclodextrin$ increased, especially in cases of cholic acid and ursodeoxycholic acid. Solubility increase of bile acids from their ${\beta}-cyclodextrin$ inclusion complex followed the order : cholic acid>ursodeoxycholic acid>chenodeoxycholic acid>deoxycholic acid>lithocholic acid. It seems that solubility of inclusion complexes was directly related with the hydrophilicity of bile acids.