Rolling or Two-Stage Aggregation of Platelets on the Surface of Thin Ceramic Coatings under in Vitro Simulated Blood Flow Conditions

Abstract

The process of modern cardiovascular device fabrication should always be associated with an investigation of how surface properties modulate its hemocompatibility through plasma protein adsorption as well as blood morphotic element activation and adhesion. In this work, a package of novel assays was used to correlate the physicochemical properties of thin ceramic coatings with hemocompatibility under dynamic conditions. Different variants of carbon-based films were prepared on polymer substrates using the magnetron sputtering method. The microstructural, mechanical, and surface physicochemical tests were performed to characterize the coatings, followed by investigation of whole human blood quality changes under blood flow conditions using the “Impact R” test, tubes’ tester, and radial flow chamber assay. The applied methodology allowed us to determine that aggregate formation on hydrophobic and hydrophilic carbon-based coatings may follow one of the two different mechanisms dependent on the type and conformational changes of adsorbed blood plasma proteins.

Polyelectrolyte Multilayer Films Modification with Ag and rGO Influences Platelets Activation and Aggregate Formation under In Vitro Blood Flow

“…Wettability influences the time-dependent conformational changes in adsorbed proteins and mediate adsorption kinetics and binding strengths [ 29 ], as well as subsequent protein activity [ 30 , 31 ]. Results of plasma protein adsorption presented in this study agree with the previous work [ 32 ], where protein adsorption increased on surface with higher hydrophobicity. Moreover, this research has shown that an increase in wettability was positively correlated with changes of coating hemocompatibility under dynamic conditions.…”

“…Platelets that adhered to the hydrophilic PEM are easily detached from the surface under applied shear forces and less likely formed aggregates than on hydrophobic surface. In our previous work we have shown that the described effect is related to higher contribution of the von Willebrand factor in aggregate formation when blood gets into the contact with the hydrophilic surface [32]. In this study we have also observed the higher number of circulating aggregates in the presence of hydrophilic coatings that was correlated with a lower contribution of the P-selectin positive platelets.…”

Evaluating medical device and material thrombosis under flow: current and emerging technologies

“…191 Recently, the study of platelet aggregation on carbon-based ceramic coatings under blood flow revealed interesting insights into the different mechanisms of aggregate formation. 192 Platelet aggregation on hydrophobic carbon-coated surfaces at shear rates of 1800 s −1 was found to be dependent upon platelet activation. Under the same shear conditions, platelet aggregation on the more hydrophilic carbon-coatings were not shown to be reliant on the platelet activation state.…”

“…Under the same shear conditions, platelet aggregation on the more hydrophilic carbon-coatings were not shown to be reliant on the platelet activation state. 192 Some of the advantages provided by the cone-and-plate method includes the ability to impart uniform shear stress across the sample and over a wide range of shear conditions (up to order of 10 5 s −1 ), 162 and the ability to test different materials, with relatively small blood volumes with the potential for real-time outputs. 174,177 A similar set-up with parallel plate geometries exists, (not to be confused with parallel plate flow chambers as discussed in section 3.5) which utilises a flat, rotating plate instead of a cone geometry.…”

Bioactive Glass Coated Zirconia for Dental Implants: a review

“…Their biological inertness and electrical passivation have made ceramics a promising material in the medical equipment and medicine. In comparison with metallic implants, zirconia-based ceramics show minimum ion release and are biologically inert [14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32]. Modern Ti implant technologies are being introduced due to possible combination of immunologic and aesthetic aspects of Ti and Ti alloys.…”