AFM force spectroscopy and its applications on micro biomechanics

基于原子力显微镜技术的力谱技术是一种高灵敏度的力学检测方法.它能够以前所未有的精度, 在微观生物力学领域表征组织、细胞、生物膜、蛋白质、核酸、功能材料等目标对象, 探索其包括形貌、化学信息、导电性、静电力以及生物学特性在内的等信息, 并且能够对其进行分子级别精度的三维操纵. 从而对分子结构与构象变化, 分子间的相互作用以及反应历程实现单分子水平的实时--原位观测, 提供了其他测试方法不能完成的实验设计之可能性.本文首先介绍了原子力显微镜及其力谱技术的原理, 以及影响测量结果的各个参数的物理意义; 其次按照单个目标对象与配对目标对象的区分方式, 详细介绍了力谱技术在微观生物力学各个尺度上的研究进展; 之后介绍了力谱技术结合成像模式下的发展和应用; 最后对设备的改进和本研究领域发展方向进行了展望.     

Advance from biomechanics to mechanobiology

本文介绍了现代生物力学的发展历程和冯元帧先生的贡献、力学生物学的概念与发展以及我国生物力学的发展历程和力学生物学的研究新进展;思考了从生物力学到力学生物学的进展与现状;展望了我国生物力学学科发展的愿景.     

CELL AND MOLECULAR BIOMECHANICS: PERSPECTIVES AND CHALLENGES

As an intriguing interdisciplinary research field,cell and molecular biomechanics is at the cutting edge of mechanics in general and biomechanics in particular.It has the potential to provide a quantitative understanding of how forces and deformation at tissue,cellular and molecular levels affect human health and disease.In this article,we review the recent advances in cell and molecular biomechanics,examine the available computational and experimental tools,and discuss important issues including protein deformation in mechanotransduction,cell deformation and constitutive behavior,cell adhesion and migration,and the associated models and theories.The opportunities and challenges in cell and molecular biomechanics are also discussed.We hope to provide readers a clear picture of the current status of this field,and to stimulate a broader interest in the applied mechanics community.     

薄壁细胞受微吸管与探针共同作用接触模型及数值模拟

建立了以典型的薄壁球型植物细胞为原型的细胞、微吸管及探针接触模型.模型的细胞壁采用封闭球形薄膜,其本构关系为体积不可压超弹性,膜球内充满有压流体以模拟细胞质.应用轴对称几何非线性方法得出了基本微分方程组,并应用龙格-库塔法进行了求解;同时,应用流固耦合有限元法进行了数值模拟以资比较.两种方法得出了较为一致的变形和应力分...     

Mechanopathology of red blood cell diseases — Why mechanics matters

During the onset of a disease a cell may experience alterations in both the composition and organization of its cellular and molecular structures. These alterations may eventually lead to changes in its geometrical and mechanical properties such as cell size and shape, deformability and adhesion. As such, knowing how diseased cells respond to mechanical forces can reveal ways by which they differ from healthy ones. Here, we will present biomechanistic insights into red blood cell related diseases that manifest mechanical property changes and how they directly contribute to the pathophysiology of diseases. By conducting cell and molecular mechanics studies, not only can we elucidate changes in the structure-property-function relationship of diseased cells, we can also exploit the new knowledge gained to develop biomechanics based devices that may better detect and diagnose these diseases as well as help identify important biomechanical targets for possible therapeutic interventions.     

用表面微纳米技术研究细胞水平的生物力学

文章介绍了作者所在的实验小组近年来在用表面微纳米技术研究细胞生物学方面取得的进展.由于细胞的尺寸在数微米到数十微米之间,应用微纳米技术可以精细地调控细胞微观环境.作者所在的实验小组应用微流控系统以及表面化学修饰等方法,对细胞正常行为和病理行为进行了一系列研究.通过设计力学刺激装置,对细胞骨架的主要成分———肌动蛋白对细...     

血红细胞力学性能的纳米压痕实验和有限元模拟

采用纳米压痕技术和有限元方法研究了血红细胞的生物力学性能. 进行了血红细胞的纳米压痕实验, 得到了血红细胞的材料参数和变形形貌; 在实验基础上, 建立了血红细胞的三维有限元模型, 模拟了血红细胞的压痕载荷-位移曲线, 并考虑了参数效应. 数值模拟结果和实验数据符合很好. 通过改变压头与材料之间的摩擦系数和压头曲率半径等参数, 比较了载荷-位移曲线的变化情况. 研究表明摩擦系数对压痕载荷-位移曲线和应力分布影响很小, 而压头曲率对载荷-位移曲线的影响明显.     

环境生物物理学

综述了环境生物物理学内容、研究方法、环境生物物理学的发展状况与取得的成就,并对今后环境生物物理学的进一步发展作了展望 。