Sugumaran Pon Janani, Liu Xiao-Li, Herng Tun Seng, Peng Erwin, Ding Jun
Department of Materials Science and Engineering , 9 Engineering Drive 1 , Singapore 117574.
The College of Life Science , Northwest University , Xi'an , Shaanxi 710069 , China.
ACS Appl Mater Interfaces. 2019 Jun 26;11(25):22703-22713. doi: 10.1021/acsami.9b04261. Epub 2019 Jun 17.
Because of their high magnetization and suitable biocompatibility, iron-oxide nanoparticles (IONPs) have been widely employed in various biomedical applications, including magnetic hyperthermia for cancer treatment. In many cases, the colloidal stability requirement will limit the usage of ferromagnetic particles that are usually associated with good magnetic response. To address this challenge, a stable carrier for better colloidal stability regardless of the size or shape of the IONPs while at the same time providing enhanced magnetic hyperthermia heating performance is required. In this work, IONPs of different sizes (4, 8, 20, 45, and 250 nm) were engineered to reside in the graphene oxide (GO) sheet carrier, which were stable in aqueous solution even in the presence of a strong magnetic field. Out of various IONPs sizes, highest specific absorption rate (SAR) value of 5020 W g was obtained with 45 nm GO-IONPs nanocomposites at a frequency and alternating magnetic field of 400 kHz and 32.5 kA m, respectively. The calculated intrinsic loss power (ILP) was 12.21 nH m kg, which is one of the highest ILP values reported for synthesized IONPs to the best of our knowledge. To enhance the excellent colloidal stability in biological environment, the GO-IONPs nanocomposites can be further grafted with polyethylene glycol (PEG) because agglomeration of pristine GO sheets occurs because of adsorption of cations. High ILP values could be well maintained even after PEG coating. The PEGylated 45 nm GO-IONP showed excellent antitumor efficacy in 4T1-tumor model mice by inhibiting tumor progression within a safe dosage range. Overall, the novel nanocomposite in this work-PEG-GO-IONP-possesses high hyperthermia performance, excellent colloidal stability in biological environment, and availability of functional groups in GO and can be utilized for tagging in various biomedical applications.
由于具有高磁化强度和合适的生物相容性，氧化铁纳米颗粒（IONPs）已被广泛应用于各种生物医学领域，包括用于癌症治疗的磁热疗。在许多情况下，胶体稳定性要求会限制通常具有良好磁响应的铁磁颗粒的使用。为应对这一挑战，需要一种稳定的载体，无论IONPs的尺寸或形状如何，都能实现更好的胶体稳定性，同时提供增强的磁热疗加热性能。在这项工作中，不同尺寸（4、8、20、45和250 nm）的IONPs被设计负载于氧化石墨烯（GO）片载体中，即使在强磁场存在下，它们在水溶液中也很稳定。在各种IONPs尺寸中，45 nm的GO-IONPs纳米复合材料在频率为400 kHz、交变磁场为32.5 kA/m时，获得了最高比吸收率（SAR）值5020 W/g。计算得到的本征损耗功率（ILP）为12.21 nH m/kg，据我们所知，这是合成IONPs报道的最高ILP值之一。为提高在生物环境中的优异胶体稳定性，GO-IONPs纳米复合材料可进一步接枝聚乙二醇（PEG），因为原始GO片会因阳离子吸附而发生团聚。即使在PEG包覆后，高ILP值仍能得到很好的保持。聚乙二醇化的45 nm GO-IONP在4T1肿瘤模型小鼠中通过在安全剂量范围内抑制肿瘤进展显示出优异的抗肿瘤效果。总体而言，这项工作中的新型纳米复合材料——PEG-GO-IONP——具有高热疗性能、在生物环境中优异的胶体稳定性以及GO中官能团的可用性，可用于各种生物医学应用中的标记。
