Water Solubilization of Phthalocyanine Derivatives via Interactions of Long Alkyl Chains and Cyclodextrins: Potential Complexes for Photodynamic Therapy

摘要

Five types of cyclodextrins, based on alpha-cyclodextrin (alpha-CDx) and beta-cyclodextrin (beta-CDx), were used to make hydrophobic phthalocyanine (Pc) derivatives with long alkyl chains soluble in waterviaa high-speed vibration milling method. Aqueous solutions of DMe-beta-CDx-based complexes were found to be the most stable, for at least 1 week over those containing alpha-CDx. Although DMe-beta-CDx complexes containing a free-base Pc and Zn-Pc with eight dodecyl chains showed greater solubility than their alpha-CDx-base counterparts, alpha-CDx complexes containing a free-base Pc and Zn-Pc with eight dodecyl chains show no self-aggregation of the Pcs and, as a result, exhibit fluorescence signals. Overall, it was found that the alpha-CDx-Zn-Pc complex exhibits higher photodynamic activity than that of the commercially available and widely used photosensitizer Photofrin.