Superparamagnetic magnetite nanocrystal clusters as potential magnetic carriers for the delivery of platinum anticancer drugs

Magnetic nanoparticles are promising carriers for targeted drug delivery. Superparamagnetic magnetite nanocrystal clusters modified with sodium carboxymethylcellulose were prepared by an in situ hydrothermal procedure in this study. The composition, morphology, and magnetic property of the clusters have been characterized by SEM, TEM, XRD, XPS, TGA, IR, and SQUID. The clusters display excellent dimensional uniformity, strong magnetisability, good aqueous dispersibility, and modifiable functionality. By virtue of the abundant carboxylate groups on the surface of the clusters, dechlorinated cisplatin was tethered to the superparamagnetic nanoparticles. The formation and the magnetism of the conjugate have been confirmed by zeta potential, EDX, ICP-MS, XPS, and SQUID. The magnetic property is well retained in the drug-loaded clusters. In comparison with cisplatin, the conjugate can more readily enter cancer cells and exert higher cytotoxicity towards the human cervical cancer HeLa cells and the human hepatocarcinoma HepG2 cells. These nanoparticles are likely to be used as targeted carriers to deliver platinum anticancer drugs.