Polydopamine-Functionalized Superparamagnetic Magnetite Nanocrystal Clusters - Rapid Magnetic Response and Efficient Antitumor Drug Carriers.

One major focus of antitumor drug delivery is the development of suitable carriers for therapeutic molecules. Superparamagnetic iron oxide nanoparticles are promising magnetic drug carriers as they are biocompatible, biodegradable, readily tunable, superparamagnetic, and, thus, controllable by an external magnetic field. In this paper, we propose and demonstrate a bioinspired synthesis of polydopamine-functionalized superparamagnetic magnetite nanocrystal clusters for antitumor drug delivery. Firstly, an oil-phase evaporation-induced self-assembly strategy was introduced to fabricate magnetite nanocrystal clusters (MNCs), which have the advantage of increased magnetization through a synergistic effect. Secondly, the surface functionalization of the MNCs with polydopamine (PDOPA) was demonstrated. Thirdly, the antitumor drug epirubicin (EPB) was attached to the surface of MNC@PDOPA, and its applicability for use as a magnetically guided carrier for antitumor drug delivery was demonstrated. The achieved MNC@PDOPA exhibits superparamagnetic characteristics, improved magnetization behavior under an external magnetic field, well-controlled loading, and pH-responsive properties; therefore, the MNC@PDOPA is a promising nanomaterial for in vivo EPB delivery applications and tumor chemotherapy. [ABSTRACT FROM AUTHOR]