讲座题目：On the interaction of nanoparticles with the cell-from the view of mechanics

报告人：施兴华（副研究员）

时 间：4月22日（周五）下午3:00~5:00
地 点：力学楼434会议室
主持人：裴永茂 （副教授）

报告内容摘要：
     Understanding the fundamental interactions of nanoparticles (NP) with living cells is important for NP-based biomedical imaging and therapeutics, and for avoiding or mitigating potential adverse health effects following occupational or environmental exposure. For example, multi-walled carbon nanotubes (MWCNTs) have been shown to induce frustrated phagocytosis and length-dependent cytotoxicity in macrophages which suggests a role for physico-mechanical phenomena in uptake and toxicity. Here we use a combination of electron microscopy, theoretical mechanics, and coarse-grained molecular simulation to elucidate the fundamental interactions of MWCNTs with eukaryotic cell membranes. Both simulation and experiment show that the primary mode of MWCNT endocytosis is tip-entry, where the entry angle is governed by elastic and surface forces at the tube-bilayer interface and the relative time scales for tube rotation and receptor diffusion. The dominance of the tip-entry mode has important implications for uptake, cytotoxicity, and safety of MWCTS and other one-dimensional nanomaterials. Meanwhile, we also investigate the role of elasticity of NP as it being wrapped by the membrane. We show that there exist three distinct wrapping phases - full wrapping, partial wrapping and no wrapping - depending on the vesicle size, the adhesion energy, the surface tension of the membrane, and the bending rigidity of the vesicle. In particular, the bending rigidity is found to play a critical role. These results are of fundamental importance not only to understanding vesicular transport but also to modeling endocytosis/phagocytosis of elastic NP into cells.

报告人简介：
     施兴华，1978年2月生，博士，副研究员。2001年毕业于2138cn太阳集团古天乐力学与工程科学系，获学士学位。2004年毕业于中国科学院力学研究所，获硕士学位。2005年1月赴德国马普协会金属所攻读博士学位，后于2006年8月转赴美国布朗大学（Brown University）继续攻读。于2010年8月获布朗大学固体力学博士学位。博士毕业后在该校进行了3个月的博士后工作，于2011年1月加入中国科学院力学所工作。学术研究方向和兴趣包括碳纳米材料的力学行为，微纳米结构的变形机理，纳米颗粒以及碳纳米管的毒性等。