Zhang Yixian, Xu Yiran, Xi Xiangyi, Shrestha Surakshya, Jiang Pengfei, Zhang Wenjing, Gao Changyou
MOE Key Laboratory of Macromolecular Synthesis and Functionalization, Department of Polymer Science and Engineering, Zhejiang University, Hangzhou 310027, China.
J Mater Chem B. 2017 May 21;5(19):3521-3530. doi: 10.1039/c7tb00344g. Epub 2017 Apr 26.
The extensive development and application of engineered nanoparticles (NPs) in various fields worldwide have been subjected to increasing concern due to their potential hazards to human health and the environment. Therefore, a simple, economical, and effective method for suppressing the toxicity of metal-based nanomaterials is needed. In this study, glutaraldehyde-crosslinked chitosan nanoparticles (CS NPs) were prepared and further modified with lysine (Ly-CS), glutamic acid (Glu-CS), or sodium borohydride reduction (R-CS), and used to suppress cytotoxicity induced by copper oxide NPs (CuO NPs) through chelation with intracellularly released copper ions. All three kinds of CS NPs had similar sizes of ∼100 nm in a dry state and ∼200 nm in cell culture medium, as determined by scanning electron microscopy, transmission electron microscopy, and dynamic light scattering. The chelating efficiency of different CS NPs followed the order Ly-CS > Glu-CS > R-CS. The CS NPs showed minimal or no toxicity to three different cell lines (HepG2, A549, and RAW264.7 cells) at 100 μg mL with similar cell internalization and exocytosis processes. Comparatively, RAW264.7 cells exhibited higher endocytosis and exocytosis rates, as revealed by flow cytometry and confocal laser scanning microscopy. CS NPs were found as agglomerates inside A549 cells and RAW264.7 cells, with the amount of agglomerates inside RAW264.7 cells decreasing significantly with prolonged incubation. All three CS NPs, especially Ly-CS and Glu-CS NPs, efficiently suppressed the cytotoxicity induced by CuO NPs, and reduced the intracellular level of reactive oxygen species.
由于工程纳米粒子（NPs）对人类健康和环境具有潜在危害，其在全球各个领域的广泛开发和应用已受到越来越多的关注。因此，需要一种简单、经济且有效的方法来抑制金属基纳米材料的毒性。在本研究中，制备了戊二醛交联的壳聚糖纳米粒子（CS NPs），并用赖氨酸（Ly-CS）、谷氨酸（Glu-CS）或硼氢化钠还原（R-CS）对其进行进一步修饰，并通过与细胞内释放的铜离子螯合来抑制氧化铜纳米粒子（CuO NPs）诱导的细胞毒性。通过扫描电子显微镜、透射电子显微镜和动态光散射测定，所有三种CS NPs在干燥状态下尺寸相似，约为100 nm，在细胞培养基中约为200 nm。不同CS NPs的螯合效率顺序为Ly-CS > Glu-CS > R-CS。在100 μg/mL时，CS NPs对三种不同细胞系（HepG2、A549和RAW264.7细胞）表现出最小或无毒性，且细胞内化和胞吐过程相似。相比之下，流式细胞术和共聚焦激光扫描显微镜显示，RAW264.7细胞表现出更高的内吞和胞吐率。在A549细胞和RAW264.7细胞内发现CS NPs呈团聚体，随着孵育时间延长，RAW264.7细胞内的团聚体数量显著减少。所有三种CS NPs，尤其是Ly-CS和Glu-CS NPs，均能有效抑制CuO NPs诱导的细胞毒性，并降低细胞内活性氧水平。
