Study on the inclusion complexes of cryptotanshinone with beta-cyclodextrin and hydroxypropyl-beta-cyclodextrin.

The inclusion complexes of beta-cyclodextrin (beta-CD) and HP-beta-cyclodextrin (HP-beta-CD) with a kind of tanshinone, cryptotanshinone (CTan) were investigated by using spectrophotometry. Stable inclusion complexes were established in solution and in solid state and were characterized by UV, IR and 1H NMR spectra, respectively. The optimum pH for inclusion is about 7.5. Stoichiometry of the inclusion complex is 1:1. The stabilities of beta-CD and HP-beta-CD to CTan were in the order: beta-CD