Design and characterisation of doxorubicin-releasing chitosan microspheres for anti-cancer chemoembolisation

The aims of this study were to design and characterise doxorubicin-loaded chitosan microspheres for anti-cancer chemoembolisation. Doxorubicin-loaded chitosan microspheres were prepared by emulsification and cross-linking methods. Doxorubicin-chitosan solution was initially complexed with tripolyphosphate (TPP) to improve drug loading capabilities. Doxorubicin-loaded chitosan microspheres were highly spherical and had approximately diameters of 130-160 µm in size. Drug loading amount and loading efficiency were in the range 3.7-4.0% and 68.5-85.8%, respectively, and affected by TPP concentration, drug levels and cross-linking time. Doxorubicin release was affected by TPP complexation, cross-linking time and release medium. Especially, lysozyme in release media considerably increased drug release. Synergistic anti-cancer activities of doxorubicin-releasing chitosan microspheres were confirmed to VX2 cells in the rabbit auricle model compared with blank microspheres. Doxorubicin-loaded chitosan microspheres can efficiently be prepared by TPP gelation and cross-linking method and developed as multifunctional anti-cancer embolic material.