Adsorption of doxorubicin hydrochloride on glutaric anhydride functionalized Fe3O4@SiO2 magnetic nanoparticles.

Since Fe3O4 nanoparticles synthesized by plant extracts possess good bio-compatibility and superparamagnetic properties, the possibility of these could be used as a carrier in drug delivery. In this work, doxorubicin hydrochloride (DOX), an anti-cancer drug, loaded on glutaric anhydride-functionalized magnetic nanoparticles (Fe3O4@SiO2-Glu) was investigated at varying pH values for effective drug delivery. Various factors affecting the adsorption of DOX onto the Fe3O4@SiO2-Glu were examined, where the adsorption efficiency of DOX reached 92% at a concentration of 20 mg/L employing 10 mg of Fe3O4@SiO2-Glu at 303 K in pH 7.4. However, the adsorption efficiency of DOX was decreased to 18% at acidic pH value down to 3.0, implicating that the drug releasing process was controlled by pH. Adsorption kinetics was fitting to pseudo-second-order and the isothermal adsorption conformed to Freundlich isotherm. The morphology and surface composition of the synthesized Fe3O4@SiO2-Glu were characterized by SEM, TEM, and N2 adsorption/desorption isotherms, revealing that the specific surface area being 62.6 m2/g and the size ranging from ~30 to 50 nm. The zeta potential results indicated that Fe3O4@SiO2-Glu were negatively charged in various pH from 3 to 8.5. Characterizations by FTIR and UV-Vis techniques suggested that the DOX was absorbed and it can be delivered by Fe3O4@SiO2-Glu.