文摘
This research is aimed to develop a kind of hollow nanosphere based on ¦Â-cyclodextrin-grafted ¦Á, ¦Â-poly(aspartic acid) (¦Â-CD-graft-PAsp) as drug carrier to enhance the stability of camptothecin (CPT) in aqueous media. Firstly, mono(6-(2-aminoethyl) amino-6-deoxy)-¦Â-cyclodextrin (¦Â-CDen) was synthesized by a substitution reaction between mono-6-deoxy-6-(p-tolylsulfonyl)-¦Â-cyclodextrin (6-OTs-¦Â-CD) and ethylenediamine; and then, the five-member rings in poly(l-succinimide) (PSI) were successively opened by ¦Â-CDen to obtain ¦Â-CD-graft-PAsp. The synthesized ¦Â-CD-graft-PAsp was found to form the unique hollow nanosphere with the internal hole of about 17 nm and many ¦Â-CD cavities of 0.7 nm interspersed on the shell. The drug-loading behavior of the hollow nanosphere was also evaluated by using CPT as guest molecule of ¦Â-CD. It was worth of note that the ¦Â-CD-graft-PAsp hollow nanosphere as carrier enhanced the stability of CPT in aqueous media, and the CPT from the ¦Â-CD-graft-PAsp hollow nanosphere displayed a sustained release profile and hence resulted in the essential decrease of cytotoxicity to L929 cell line. Furthermore, almost no cytotoxicity of the ¦Â-CD-graft-PAsp is desirable for the application of drug carrier. As a result, the ¦Â-CD-graft-PAsp hollow nanosphere showed a great potential as the carrier of CPT.
