CYCLODEXTRIN DERIVATIVES IN PHARMACEUTICS

The current cyclodextrin (CD) literature is reviewed concerning synthe sis, characterization, and pharmaceutical relevant applications of CD derivatives. Although natural CDs have been used extensively to improv e pharmaceutical properties, the effects of chemically modified CDs on the solubility, dissolution rate, and stability of drugs are overprop ortional. Concerning the parenteral application, the major interest is focussed on highly water-soluble, randomly substituted hydroxyalkyl d erivatives of beta- and gamma-CD such as 2-hydroxypropyl-beta-cyclodex trin (2-HP-beta-CD). Although the heptakis-(2,6-di-O-methyl)beta-cyclo dextrin is applied in the pharmaceutical field, 2HP-beta-CD is predest ined as a parenteral drug carrier owing to its weak hemolytic activity and intrinsically amorphous character. A minimal average degree of su bstitution is especially preferred when 2-HP-beta-CD is used as solubi lizer of pharmaceuticals for the use in parenteral applications. The i nfluence of the type, degree, and pattern of substitution of the CDs, as well as substituent effects of the guest molecule is elucidated.