Conjugation of Monodisperse Chitosan-Bound Magnetic Nanocarrier with Epirubicin for Targeted Cancer Therapy

The conjugate of epirubicin with monodisperse chitosan-bound magnetic nanocarrier was developed and its in-vitro anticancer efficacy was evaluated. Chitosan was first carboxymethylated and then covalently bound on the surface of Fe3O4 nanoparticles via carbodiimide activation. Transmission electron microscopy micrograph and dynamic light scattering measurement showed that the chitosan-bound Fe3O4 nanoparticles were monodisperse with a mean core diameter of 13.5 nm and a hydrodynamic diameter of 17.1 nm and so could be further used as magnetic drug carriers. The adsorption study indicated that the conjugate of epirubicin and the chitosan-bound magnetic nanocarrier was stable at pH 3-7 and 25-40 degrees C, and a high epirubicin loading could be achieved. The desorption kinetics showed that about 80% epirubicin released from the chitosan-bound magnetic nanocarrier after 150 and 300 min in serum and 0.03 M phosphate buffer, respectively. In vitro cytotoxicity evaluation revealed that the epirubicin-loaded magnetic conjugate was able to exhibit comparable efficacy as free epirubicin did alone. Because of the combined functions of targeted therapy and diagnosis, the novel chitosan-bound magnetic nanocarrier developed in this work will be useful in biomedicine.