Effects of bioinspired leaf vein structure on biological properties of UV laser patterned titanium alloy

Abstract

Inspired by nature, a UV laser was used to fabricate the grid and leaf vein structure on titanium alloy and polydimethylsiloxane (PDMS) coated samples, respectively. The suitable laser parameters were selected by analyzing the processing technology. The osteogenic ability of different samples and the proliferation behavior of cells on their surfaces were analyzed through cell free in vitro mineralization and cell experiments, respectively. The results show that laser patterning enhances the hydrophilicity of titanium alloy, while the -CH3 functional group in PDMS makes the sample hydrophobic. Therefore, the leaf vein structure sample appears wettability gradient by combining laser processing with PDMS material. According to the cell proliferation data, the cells maintain a good proliferation state on the four groups of samples, indicating that the samples have no cytotoxic effect. The cells are more likely to form focal adhesions and show spindle stretching on the laser patterned samples because they have more adhesion sites. For leaf vein structure, cells tend to adhere, diffuse, fuse, and proliferate in and near the leaf vein pattern. Laser patterning produces different wettability and surface morphology regions on the sample surface, and the resulting regional differentiation can be used to control the directional adhesion and growth of cells.