Polymer-metal complex nanoparticles-containing cisplatin and amphiphilic block copolymer for anticancer drug delivery

摘要

Polymer-metal complex nanoparticles-containing cisplatin (cis-dichlorodiammineplatinum(II)), an anticancer drug, was prepared by a ligand-exchange reaction of cisplatin with core-shell-type poly(citric acid)-b-poly(caprolactone)-b-poly(cit- ric acid) (PCA-PCL-PCA). The resulting polymer-platinum complex nanoparticles showed a high loading capacity (up to 44.2% w/w). The TEM observation confirmed that the nanoparticles with spherical shape were formed by the mixing of PCA-PCL-PCA copolymer and cisplatin. According to TEM and DLS, polymer-cisplatin complex nanoparticles showed larger diameters compared with empty block copolymer attributed to some intermolecular crosslinkings through polymer-platinum (II) complex formation. The release profile of the platinum (II) complexes in phosphate-buffered sal- ine medium at 37 °C indicated sustained manner of drug release. In vitro cytotoxicity evaluated by MTT assay, demon- strated that the PCA-PCL-PCA block copolymer does not exhibit apparent cytotoxicity. PCA-PCL-PCA-cisplatin complex nanoparticles showed greater cytotoxicity to HeLa cell line contrasted with free cisplatin, attributed to existence of poly (citric acid) moiety.