Experimental research on laser interference micro/nano fabrication of hydrophobic modification of stent surface.

Coronary artery disease (CAD) has become one of the important causes of human death, and coronary stent implantation is one of the most effective methods for the treatment of CAD. But the current clinical treatment has a high long-term restenosis rate and is easy to form late stent thrombosis. In order to solve these problems, coronary artery stent surface was directly modified by laser interference lithography and the highly ordered concave structures were fabricated. The morphology and contact angle (CA) of the microstructure were measured with scanning electron microscopy (SEM) and CA system. The water repellent property of the stent was also evaluated by the method of contacting the water drop with the stent and then separating. The result showed that the close-packed concave structure with the period of about 12.194 μm can be fabricated on the stent surface under special parameters (laser energy density of 3.5 J/cm-2, incident angles of 3°, exposure time of 80 s) by the three-beam laser interference of 1064 nm and the form structure has good water repellency with contact angle of 120°.