考虑介质粘弹性效应的特异性粘附力学机理研究

For the adhesion problem of molecular bond clusters mediated by the specific molecules interaction, many existing studies on the specific adhesion focus on the random chemical reaction between molecules or the coupling effect between molecule reaction and deformation of elastic medium. However, the experiment has recently demonstrated the viscosity of viscoelastic medium plays more important role than elasticity of medium in specific adhesion, and very few theoretical works have addressed the specific adhesion between viscoelastic mediums. The underlying mechanical mechanism involved in the adhesion process remains unclear. In the present project, by considering the coupling interactions between diffusion of mobile molecule, molecular interaction and viscoelastic deformation of medium, a coupled stochastic reaction – diffusion – viscoelasticity model for specific adhesion between viscoelastic mediums is conducted. Based on this model, we quantitatively investigate the effect of viscoelasticity on specific adhesion problems between medium – medium and medium – particle, and find the mechanical mechanism of viscoelasticity on such specific adhesion. Additionally, the competitions in time scale between molecule reactions, molecule diffusion and creep of viscoelastic medium are also determined, based on these competitions we show the multiple mechanisms for medium – particle specific adhesion. These results are helpful for understanding the cell behavior from mechanical point.

针对经由特异性分子间发生化学作用，生成粘附分子键群簇而形成的特异性粘附问题，很多现有工作仅集中于研究粘附分子化学反应动力学机制或粘附分子随机化学反应-弹性介质间的耦合效应，而最近实验研究发现介质粘弹性性质对特异性粘附的影响作用甚至超过介质弹性性质的影响，但目前对于粘弹性介质间特异性粘附的理论研究较为缺乏，涉及这一特异性粘附过程中的粘弹性效应的力学机理尚未清楚。本项目就粘弹性介质间特异性粘附问题，综合考虑粘附分子随机化学反应、粘附分子扩散及介质粘弹性变形间的相互作用，明确这些因素的内在耦合关系，建立随机-扩散-粘弹性耦合的特异性粘附模型，定量研究介质-介质、介质-颗粒特异性粘附中的介质粘弹性效应，阐述介质粘弹性性质影响特异性粘附行为的力学机理，分析粘附分子随机化学反应、粘附分子扩散及介质粘弹性蠕变间的时间竞争关系，揭示介质-颗粒间的多重特异性粘附机制，为理解细胞生物学行为提供理论依据。

针对经由特异性分子间发生化学作用，生成粘附分子键群簇而形成的特异性粘附问题，很多现有工作仅集中于研究粘附分子化学反应动力学机制或粘附分子随机化学反应-弹性介质间的耦合效应，而最近实验研究发现介质粘弹性性质对特异性粘附的影响作用甚至超过介质弹性性质的影响，但目前对于粘弹性介质间特异性粘附的理论研究较为缺乏，涉及这一特异性粘附过程中的粘弹性效应的力学机理尚未清楚。本项目就粘弹性介质间特异性粘附问题，综合考虑粘附分子随机化学反应、粘附分子扩散及介质粘弹性变形间的相互作用，明确这些因素的内在耦合关系，建立随机-扩散-粘弹性耦合的特异性粘附模型，定量研究介质-介质、介质-颗粒特异性粘附中的介质粘弹性效应，阐述介质粘弹性性质影响特异性粘附行为的力学机理，分析粘附分子随机化学反应、粘附分子扩散及介质粘弹性蠕变间的时间竞争关系，揭示介质-颗粒间的多重特异性粘附机制，为理解细胞生物学行为提供理论依据。