JNM Journal of Nanomaterials 1687-4129 1687-4110 Hindawi 10.1155/2018/4341580 4341580 Research Article Ammonium Bisphosphonate Polymeric Magnetic Nanocomplexes for Platinum Anticancer Drug Delivery and Imaging with Potential Hyperthermia and Temperature-Dependent Drug Release http://orcid.org/0000-0003-4164-2176 Zhang Ruiruizhang@vt.edu1 Fellows Benjaminbfellow@clemson.edu2 http://orcid.org/0000-0002-1373-2556 Pothayee Nikornnikorn.pothayee@nih.gov3 Hu Nannan86@vt.edu1 Pothayee Niponniponpo@vt.edu1 Jo Amiamijo52@vt.edu1 Bohórquez Ana C.ana.bohorquez@ufl.edu4 Rinaldi Carloscarlos.rinaldi@bme.ufl.edu4 Mefford Olin Thompsonmefford@clemson.edu2 Davis Richey M.rmdavis@vt.edu1 http://orcid.org/0000-0002-6291-6095 Riffle Judy S.jriffle@vt.edu1 Espinosa Ana 1 Department of Chemistry Department of Chemical Engineering and Macromolecules Innovation Institute Virginia Tech Blacksburg VA 24061 USAvt.edu 2 Department of Materials Science and Engineering and the Center for Optical Materials Science and Engineering (COMSET) Clemson University Clemson SC 29634 USAclemson.edu 3 Laboratory of Functional and Molecular Imaging National Institute of Neurological Disorders and Stroke National Institutes of Health Bethesda MD 20892 USAnih.gov 4 J. Crayton Pruitt Family Department of Biomedical Engineering and Department of Chemical Engineering University of Florida Gainesville FL 32611 USAufl.edu 2018 582018 2018 29 03 2018 04 06 2018 11 06 2018 582018 2018 Copyright © 2018 Rui Zhang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Novel magnetite-ammonium bisphosphonate graft ionic copolymer nanocomplexes (MGICs) have been developed for potential drug delivery, magnetic resonance imaging, and hyperthermia applications. The complexes displayed relatively uniform sizes with narrow size distributions upon self-assembly in aqueous media, and their sizes were stable under simulated physiological conditions for at least 7 days. The anticancer drugs, cisplatin and carboplatin, were loaded into the complexes, and sustained release of both drugs was observed. The transverse NMR relaxivities (r2s) of the complexes were 244 s−1 (mM Fe)−1 which is fast compared to either the commercial T2-weighted MRI agent Feridex IV® or our previously reported magnetite-block ionomer complexes. Phantom MRI images of the complexes demonstrated excellent negative contrast effects of such complexes. Thus, the bisphosphonate-bearing MGICs could be promising candidates for dual drug delivery and magnetic resonance imaging. Moreover, the bisphosphonate MGICs generate heat under an alternating magnetic field of 30 kA·m−1 at 206 kHz. The temperature of the MGIC dispersion in deionized water increased from 37 to 41°C after exposure to the magnetic field for 10 minutes, corresponding to a specific absorption rate of 77.0 W·g−1. This suggests their potential as hyperthermia treatment agents as well as the possibility of temperature-dependent drug release, making MGICs more versatile in potential drug delivery applications.

National Science FoundationDMR 1263248DMR 1106182DMR 0805179