The Theoretical Research On The Influence Of Surface Topography On Specific Adhesion

Specific adhesion between cell and cell or cell and ECM formed through specific interaction of adhesive molecules is the fundamental biological processes involved in many physiological and pathological phenomena. For example, most cells must adhere to other cells or ECM to be alive; Cells with repair materials or implant surface adhesion directly affect the implantation efficacy and its service life in the clinic. Nano-topography of the cell envelope or the extracellular matrix make a direct impact on the growth and migration of cells; repair materials and implant surface morphology (such as surface roughness and rules nicks, etc.) play a particularly critical role on the ability of cell adhesion. To this end, this paper theoretically investigates the influence of surface topography on the specific adhesion between soft elastic media. Since cells, extracellular matrix e repair material and the basement membrane of the implant are soft elastic substance, their mechanical behavior can be approximately expressed by the continuum mechanics, the stochastic breaking/reforming of adhesive molecular bonds is described by classical Bell’s model. We present an elastic-stochastic model to study the specific adhesion of two soft elastic materials with wavy contact interface, or second order of rough surface. Based on this model, we give the adhesion strength function depend on amplitude and the wavelength of the wavy surface. Our results show that, appropriate adhesion size or stress concentration index can decrease or increase the interfacial boundary stress concentration to change the adhesion strength. When surface adhesion size is small enough, the adhesion strength is mainly determined by the surface morphology of the first order. However, with the second-order surface fluctuations increasing, organization between different surfaces should be considered to accurate describe the influence of interface morphology on adhesion strength. These findings are in qualitative agreement with experimental observations and provide fundamental knowledge on cell-substrate interactions which is important for tissue engineering.