Jiangsu Key Laboratory of Biofunctional Material, College of Chemistry and Material Science, Nanjing Normal University, Nanjing 210023, China.
Jiangsu Key Laboratory of Biofunctional Material, College of Chemistry and Material Science, Nanjing Normal University, Nanjing 210023, China; Jiangsu Provincial Key Laboratory of Palygorskite Science and Applied Technology, Huaiyin Institute of Technology, Huaian 223003, China.
Int J Pharm. 2015 Dec 30;496(2):965-75. doi: 10.1016/j.ijpharm.2015.10.052. Epub 2015 Oct 26.
A new strategy is proposed to synthesize a kind of Au@SiO2 core-shell structure with methotrexate (MTX) loaded within it. Firstly, MTX molecules are attracted to the surface and vicinity of Au nanoparticles (NPs). Then the enriched MTX molecules on the surface of Au NPs have a good chance to be wrapped into the core-shell structure when SiO2 is uniformly deposited on the Au core. Secondly, the effect of Au amount and MTX content on the drug-loading capacity is emphatically studied and the result shows that core-shell structure plays a vital role in drug loading. In addition, the biodegradation process is also examined in phosphate buffer solution (PBS) at 37°C. The results show that the biodegradation of Au-MTX@SiO2 core-shell structure can be divided into two stages: the release of drug together with the fragmentation of core-shell structure and the subsequent dissolution of SiO2 layers. Lastly, in vitro bioassay tests give the evidence that obvious tumor inhibition can be achieved in presence of Au-MTX@SiO2 NPs even at low concentration and the efficacy can be greatly enhanced by the photothermal therapy on Au cores.
提出了一种新策略来合成负载甲氨蝶呤（MTX）的 Au@SiO2 核壳结构。首先，MTX 分子被吸引到 Au 纳米粒子（NPs）的表面和附近。然后，当 SiO2 均匀沉积在 Au 核上时，表面上富集的 MTX 分子很有机会被包裹到核壳结构中。其次，着重研究了 Au 量和 MTX 含量对载药量的影响，结果表明核壳结构对载药具有重要作用。此外，还在 37°C 的磷酸盐缓冲溶液（PBS）中检查了生物降解过程。结果表明，Au-MTX@SiO2 核壳结构的生物降解可以分为两个阶段：药物的释放以及核壳结构的碎裂，随后是 SiO2 层的溶解。最后，体外生物测定试验表明，即使在低浓度下，Au-MTX@SiO2 NPs 也能实现明显的肿瘤抑制，并且通过 Au 核的光热治疗可以大大增强疗效。
