Graphene Oxide Covalently Grafted Fe2B@SiO2 Nanoparticles for Epirubicin Loading and Releasing

In this work, stable superparamagnetic core-shell Fe(2)B@SiO(2) nanoparticles were prepared by "one pot" chemical reduction of ferric ion salts with NaBH(4) and silica shell coating in the presence of citric acid stabilizer. The X-ray (XRD) and selection of electron diffraction (SAED) revealed that Fe(2)B@SiO(2) nanoparticles were chiefly composed of silica shell and Fe(2)B with a small amount of alpha-Fe. Then, graphene oxide (GO) was assembled onto core-shell Fe(2)B@SiO(2) nanoparticles for Epirubicin (EPI) loading and releasing, and the adsorption isotherm of EPI on Fe(2)B@SiO(2)@GO was analyzed. The results showed, the adsorption process includes two steps, due to the pi-pi stacking effect of EPI on the Fe(2)B@SiO(2)@GO. The EPI loading efficiency of the magnetic nanoparticles was as high as 90%, while the EPI-loaded core-shell Fe(2)B@SiO(2) nanoparticles showed an obvious pH controlled drug release behavior, and showed lower cumulative release rate when pH is 7.4 than that when pH is 5.7. The prepared nanoparticles demonstrated potential application in killing tumor cells while minimizing the toxicity to normal tissues.