The Effect of Plasma Treatment on the Mechanical and Biological Properties of Polyurethane Artificial Blood Vessel

Abstract

In recent years, the incidence of cardiovascular disease has increased annually, and the demand for artificial blood vessels has been increasing. Due to the formation of thrombosis and stenosis after implantation, the application of many materials in the human body has been inhibited. Therefore, the choice of surface modification process is very important. In this paper, small-diameter polyurethane artificial blood vessels were prepared through electrospinning, and their surfaces were treated with plasma to improve their biological properties. The samples before and after plasma treatment were characterized by SEM, contact angle, XPS, and tensile testing; meanwhile, the cell compatibility and blood compatibility were evaluated. The results show that there are no significant changes to the fiber morphology or diameter distribution on the surface of the sample before and after plasma treatment. Plasma treatment can increase the proportion of oxygen-containing functional groups on the surface of the sample and improve its wettability, thereby increasing the infiltration ability of cells and promoting cell proliferation. Plasma treatment can reduce the risk of hemolysis, and does not cause platelet adhesion. Due to the etching effect of plasma, the mechanical properties of the samples decreased with the extension of plasma treatment time, which should be used as a basis to balance the mechanical property and biological property of artificial blood vessels. But on the whole, plasma treatment has positive significance for improving the comprehensive performance of samples.

Keywords: artificial blood vessels; biocompatibility; electrospinning; mechanical properties; plasma treatment; polyurethane.

Figure 1

Fiber morphology and measured results of fiber diameter on the surface of the samples with plasma processed for different time periods—(a,b) 0 s, (c,d) 30 s, (e,f) 60 s, (g,h) 90 s, (i,j) 120 s.

Figure 1

Fiber morphology and measured results of fiber diameter on the surface of the samples with plasma processed for different time periods—(a,b) 0 s, (c,d) 30 s, (e,f) 60 s, (g,h) 90 s, (i,j) 120 s.

Figure 2

Water contact angle of PU samples after different periods of plasma treatment; (a) instantaneous photos, (b) measured results of contact angle.

Figure 3

(a) XPS spectrum of untreated samples (0 s) and treated with plasma for 120 s; (a) full spectrum (CPS, Count Per Second), (b) peak fitting results.

Figure 4

Tensile test results, (a) stress–strain curve, (b) Young’s modulus and ultimate tensile strength (the bar chart represents the Young’s modulus, and the scatter chart represents the tensile strength).

Figure 5

Results of cell proliferation assay (* p < 0.05, ** p < 0.01). (a) Relative Growth Rate (RGR); the surface morphology of each sample after co-culture for (b) 0 s, (c) 30 s, (d) 60 s, (e) 90 s, (f) 120 s.

Figure 6

Hemolysis test results of samples (* p < 0.05).

Figure 7

Results of platelet adhesion test. Samples were treated for (a) 0 s, (b) 30 s, (c) 60 s, (d) 90 s, (e) 120 s.