Centre for Nanotechnology, Indian Institute of Technology Guwahati, Guwahati, Assam 781039, India.
Adv Healthc Mater. 2014 Jan;3(1):106-14. doi: 10.1002/adhm.201300090. Epub 2013 Jul 15.
Herein, a green method for the development of a novel biodegradable silver nanoparticles (NPs) impregnated alginate-chitosan-blended nanocarrier (Ag NPs-Alg-Chi NC) is reported. The synthesis of Ag NPs-Alg-Chi NC is based on the polyelectrolyte complex formation between alginate and chitosan. The composite NC is characterized by ultraviolet-visible spectroscopy, transmission electron microscopy, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, and X-ray diffraction. The Ag NPs in the NC are found to elicit anticell proliferative effect on refractory U87MG (human glioblastoma) cells at IC50 of 2.4 μg mL(-1) for Ag NPs. The cell cycle analysis shows extensive DNA damage. Elevation in reactive oxygen species level indicates induction of oxidative stress in treated cells. Mitochondrial dysfunction in cell death is evident from the depolarization of mitochondrial membrane potential (ΔΨm ). Fluorescence and SEM images of the treated cells reveal nuclear and morphological changes characteristic of apoptosis, which is further confirmed by TUNEL assay. The induction of apoptosis at low concentration of Ag NPs present in Ag NPs-Alg-Chi NC in comparison with free Ag NPs makes it a promising tool for cancer therapy.
本文报道了一种绿色方法，用于开发新型可生物降解的载银纳米粒子（Ag NPs）的海藻酸钠-壳聚糖共混纳米载体（Ag NPs-Alg-Chi NC）。Ag NPs-Alg-Chi NC 的合成基于海藻酸钠和壳聚糖之间的聚电解质复合形成。通过紫外-可见光谱、透射电子显微镜、扫描电子显微镜（SEM）、傅里叶变换红外光谱和 X 射线衍射对复合 NC 进行了表征。结果表明，NC 中的 Ag NPs 在 IC50 为 2.4μg mL(-1)时对难治性 U87MG（人神经胶质瘤）细胞表现出抗细胞增殖作用。细胞周期分析显示大量的 DNA 损伤。活性氧水平的升高表明处理细胞中诱导了氧化应激。细胞死亡中线粒体功能障碍从线粒体膜电位（ΔΨm）去极化中明显看出。用荧光和 SEM 图像观察到处理细胞的核和形态发生变化，特征为细胞凋亡，TUNEL 检测进一步证实了这一点。与游离 Ag NPs 相比，Ag NPs-Alg-Chi NC 中存在的低浓度 Ag NPs 诱导细胞凋亡，这使其成为癌症治疗的有前途的工具。
