Research on DMSO composite modification technology and anticoagulation properties of microtextured vascular stents

Medically implantable metallic stents serve as a crucial interventional treatment for vascular stenosis; however, in-stent restenosis persists at a rate of 15%–30% following implantation, substantially compromising therapeutic outcomes. In this study, a composite surface modification strategy combining U-shaped microtextures and dimethyl sulfoxide (DMSO) molecular modification was developed to fabricate novel anticoagulant stents capable of suppressing thrombus regeneration. TC4 titanium alloy (Ti–6Al–4V) vascular stents containing microtextures on the inner surface were prepared by pulsed laser etching, continuous laser welding, and infrared laser engraving. In contrast, the DMSO molecular coating was prepared by the composite chemical modification technique to obtain modified vascular stents with hydrophobic properties, and the exposure of the two CH₃ groups was the reason for the enhanced hydrophobic properties. The results of flow cytometry tests using fluorescein isothiocyanate (FITC)-CD41 antibody and PE-CD62P staining showed that the platelet activation rate on the surface of the microtextured composite DMSO-modified stents was significantly reduced, the CD62P expression rate decreased to 7.74%, and the amount of platelet adhesion was reduced considerably. Hemodynamic analysis demonstrated that, compared to smooth stents, the microtextured stent exhibited reduced shear stress oscillation amplitude along the blood flow wall. The low-shear–stress area (< 0.5 Pa) measured 33.855 mm², a 17.5% reduction, accompanied by effective inhibition of platelet activation.