抄録
A new series of peracylated β-cyclodextrins (β-CyDs) with different alkyl chains (acetyl-lauroyl) was prepared in high purity by acylating all hydroxyl groups of β-CyD using acid anhydrides in pyridine, and their physicochemical properties of solubility, hydrolsis and release and interaction capacity were evaluated. The solublity of peracylated β-CyDs in water decreased with lengthening alkyl chain, whereas that in ethanol/water increased with increase in ethanol concentration, but tended to decrease at higher ethanol concentration. The solubility parameter of peracylated β-CyDs was determined by analyzing the peak-solubility phenomenon by a modified Hildebrand equation. The alkaline hydrolysis rate of peracylated β-CyDs decreased with lengthening alkyl chain, and was about 4-fold faster than that of the corresponding fatty acid ethyl esters. The interaction of perbutanoyl-β-CyD (TB-β-CyD) with a water-soluble drug, molsidomine, in the solid state was investigated by differential scanning calorimetry (DSC). The analysis of DSC curves suggested that molsidomine and TB-β-CyD form a binary solid dispersion with a 2 : 1 (drug : TB-β-CyD) molar ratio. The rate of drug release was markedly retarded by the combination with peracylated β-CyDs in the increasing order of the hydrophobicity of host molecules.
