Kinetics of eukaryote cells adhesion under shear flow detachment on the PLD deposited surfaces

摘要

Hybryd PLD method was used for deposition high quality thin Ti,TiN,Ti(C,N)and DLC coatings.The kinetic energy of the evaporated particles was controlled by application of variation of different reactive and non reactive atmospheres during deposition.The purpose was to improve adhesion by building a bridge between the real ceramic coating and the substrate.A new layer composition layout was proposed by application of a buffer,starting layer.Advanced HRTEM investigation based on high resolution transmission electron microscopy was used to reveal structure dependence on specific atmosphere in the reactive chamber.New experimental technique to examine the crystallographic orientation based on X-ray texture tomography was applied to estimate contribution of the atmosphere to crystal orientation.Using Dictyostelium discoideum cells as a model organism for specific and nonspecific adhesion,kinetics of shear flow-induced cell detachment was studied.For a given cell,detachment occurs for critical stress values caused by the applied hydrodynamic pressure above a threshold.Cells are then removed from the substrate with an apparent first-order rate reaction that strongly depends on the stress.The threshold stress depends on cell size and physicochemical properties of the substrate,but it is not affected by depolymerization of the actin and tubulin cytoskeleton.