Selected laser methods for surface structuring of biocompatible diamond-like carbon layers

Abstract

Laser based surface structuring methods are among the fastest growing techniques and displace other surface treatments for applications such as marking, change of topography and microstructure. Such changes may lead to controlled modification of material properties, including their biocompatibility. The paper presents two laser techniques — picosecond Direct Laser Writing (DLW) and multi-beam Direct Laser Interference Lithography (DLIL). The purpose of the research was to create different shapes and dimensions of 2D and 3D periodical microstructures on the surface of thin diamond like carbon (DLC) coatings on different substrates. Resulting structures were further tested to find the influence of laser processing on the interaction of created scaffolds with the living cells in the direction of improvement of their directional growth and adhesion. The use of two different patterning methods (DLW and DLIL) allowed creation of structures with periods ranging between sub-microns to tens of microns, with different pattern resolutions, shapes (linear, dotted, crossed, hierarchical) and depths. Preliminary analyses have shown the possibility of high degree of control and improvement in the directional growth of smooth muscle cells and the proliferation of the endothelial cells, cultivated on migration channels created at DLC layers.