Division of Nanomaterials Science, EcoTopia Science Institute, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
ACS Appl Mater Interfaces. 2010 Jul;2(7):1903-11. doi: 10.1021/am100237p.
Magnetic nanoparticles (MNPs) generate heat when a high-frequency magnetic field (HFMF) is applied to them. Induction heat is useful not only for hyperthermia treatment but also as a driving force for drug-release. beta-Cyclodextrin (CD) can act as drug container because of its inclusion properties. Drugs incorporated in the CD can thus be released through the use of induction heating, or hyperthermic effects, by applying a HFMF. In this study, we have synthesized folic acid (FA) and CD-functionalized superparamagnetic iron oxide nanoparticles, FA-CD-SPIONs, by chemically modifying SPIONs derived from iron(III) allylacetylacetonate. FA is well-known as a targeting ligand for breast cancer tumor and endows the SPIONs with cancer-targeting capability. Immobilization of FA and CD on spinel iron oxide nanoparticles was confirmed by Fourier transform IR (FTIR) and X-ray photoelectron spectroscopy (XPS). The FA-CD-SPIONs have a hydrodynamic diameter of 12.4 nm and prolonged stability in water. They are superparamagnetic with a magnetization of 51 emu g(-1) at 16 kOe. They generate heat when an alternating current (AC) magnetic field is applied to them and have a specific absorption rate (SAR) of 132 W g(-1) at 230 kHz and 100 Oe. Induction heating triggers drug release from the CD cavity on the particle - a behavior that is controlled by switching the HFMF on and off. The FA-CD-SPIONs are noncytotoxic for cells. Thus, FA-CD-SPIONs can serve as a novel device for performing drug delivery and hyperthermia simultaneously.
磁性纳米粒子（MNPs）在施加高频磁场（HFMF）时会产生热量。感应加热不仅可用于热疗，还可用作药物释放的驱动力。β-环糊精（CD）因其包合性能可作为药物容器。因此，通过施加 HFMF 利用感应加热或热效应，可以将包含在 CD 中的药物释放出来。在这项研究中，我们通过化学修饰源自铁（III）烯丙基乙酰丙酮的 SPION，合成了叶酸（FA）和 CD 功能化超顺磁性氧化铁纳米粒子，FA-CD-SPION。FA 是众所周知的乳腺癌肿瘤靶向配体，使 SPION 具有癌症靶向能力。通过傅里叶变换红外（FTIR）和 X 射线光电子能谱（XPS）证实了 FA 和 CD 固定在尖晶石氧化铁纳米粒子上。FA-CD-SPION 的水动力直径为 12.4nm，在水中具有延长的稳定性。它们具有超顺磁性，在 16kOe 下的磁化强度为 51emu g(-1)。当施加交流（AC）磁场时，它们会产生热量，在 230kHz 和 100Oe 下的比吸收率（SAR）为 132W g(-1)。感应加热会触发药物从粒子上的 CD 腔中释放出来，这种行为可通过打开和关闭 HFMF 来控制。FA-CD-SPION 对细胞无细胞毒性。因此，FA-CD-SPION 可以作为一种新的装置，同时进行药物输送和热疗。
