单壁碳纳米管的生物可利用性、生物可降解性及毒性效应研究

项目名称： 单壁碳纳米管的生物可利用性、生物可降解性及毒性效应研究

项目编号： No.21277158

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 环境科学、安全科学

项目作者： 万斌

作者单位： 中国科学院生态环境研究中心

项目金额： 80万元

中文摘要： 单壁碳纳米管在环境与医学等领域的广泛应用已使人们开始极为关注其潜在的环境和健康危害。SWCNT的毒性与其生物可利用性和可降解性密切相关，而目前这方面的研究报道很少。本课题拟对具有不同表面修饰和长度分布的SWCNT的生物可利用性和可降解性及其毒性进行研究。通过考察不同SWCNT在细胞内的累积，检测SWCNT进入细胞的能力和方式及其产生的毒性变化；通过一系列光谱和电镜方法考察暴露于细胞前后SWCNT的结构变化来研究细胞对SWCNT的降解能力；同时在无细胞体系，研究吞噬溶酶体、溶酶体模拟液以及过氧化物酶溶液分别对不同SWCNT的降解能力来进一步研究SWCNT生物可降解性的原因。在此基础上，采用分子模拟方法研究SWCNT与酶蛋白的作用位点和方式，以阐释SWCNT可降解性的机制。阐明SWCNT特性与其生物可利用性和可降解性的关系将极大地有助于指导我们设计生产和使用更加安全、环保的纳米材料。

中文关键词： 单壁碳纳米管；巨噬细胞；内吞外排机制；生物可降解性；细胞自噬效应

英文摘要： The wide use of single-walled carbon nanotubes (SWCNT) in environmental and medical fields has attracted a great deal of concerns on their potential adverse effects on environment and human health. The toxicity of SWCNT is related to the bioavailability and biodegradation of SWCNT, which determines the internal exposure concentration of SWCNT. However, very limited data are available on how physicochemical properties of SWCNT influence the accumulation and degradation of SWCNT within biological system. Generally, pollutants including nanomaterials have to be accessible to cells and taken up by cells before the occurrence of toxic effects. Studies have showed a non-linear relationship between the length of SWCNT and its toxicity. CNTs in appropriate length tend to be readily taken up by cells resulting in higher internal concentration, while very long CNTs are resistant to cellular internalization, causing frustrated phagocytosis and eliciting inflammation response. Recently, biodegradation of SWCNT within biological system has been demonstrated by incubating SWCNT with phagocytes and found that once engulfed, only carboxylated SWCNT can be effectively digested by cells via the catalysis of myeloperoxidase, while pristine SWCNT was kept intact. Therefore, it is of significance to understand the relationship betwe

英文关键词： SWCNT；macrophages；mechanism for internalization and exocytosis；biodegradation；autophagic effect