Development of 3D-Printed Sulfated Chitosan Modified Bioresorbable Stents for Coronary Artery Disease

Abstract

Bioresorbable polymeric stents have attracted great interest for coronary artery disease because they can provide mechanical support first and then disappear within a desired time period. The conventional manufacturing process is laser cutting, and generally they are fabricated from tubular prototypes produced by injection molding or melt extrusion. The aim of this study is to fabricate and characterize a novel bioresorbable polymeric stent for treatment of coronary artery disease. Polycaprolactone (PCL) is investigated as suitable material for biomedical stents. A rotary 3D printing method is developed to fabricate the polymeric stents. Surface modification of polymeric stent is performed by immobilization of 2-N, 6-O-sulfated chitosan (26SCS). Physical and chemical characterization results showed that the surface microstructure of 3D-pinted PCL stents can be influenced by 26SCS modification, but no significant difference was observed for their mechanical behavior. Biocompatibility assessment results indicated that PCL and S-PCL stents possess good compatibility with blood and cells, and 26SCS modification can enhance cell proliferation. These results suggest that 3D printed PCL stent can be a potential candidate for coronary artery disease by modification of sulfated chitosan (CS).

Keywords: 3D printing; biocompatibility; bioresorbable stent; mechanical property; sulfated chitosan.

FIGURE 1

3D-printing trajectory strategy (A), 3D printer machine (B), machine methodology (C), and 3D-printed PCL stents (D).

FIGURE 2

Schematic reaction of 2-N, 6-O-sulfated chitosan (A) and aminolysis reaction of sulfated chitosan with PCL stents (B). * means the repetition of molecular structure.

FIGURE 3

SEM images of PCL stent (A–C) and S-PCL stent (D–F) with different magnifications.

FIGURE 4

Lateral crush resistance test (A), force–displacement curve (B), and stress–strain curve (C).

FIGURE 5

Degradation behavior of S-PCL stents.

FIGURE 6

Hemolytic percentage of RBCs incubated with PCL and S-PCL stent extracts at different time points.

FIGURE 7

Morphology of RBCs in extracts of PCL and S-PCL stent and PBS solution.

FIGURE 8

Effect of PCL and S-PCL stent on APTT and PT compared to PBS control.

FIGURE 9

Cell viability with different percentages of PCL and S-PCL stent extracts.

FIGURE 10

Live/Dead staining images of L929 cells seeded on the PCL and S-PCL stents after 1 and 7 days.

FIGURE 11

Cytoskeleton fluorescence staining images of L929 cells seeded on PCL and S-PCL stents after 1 and 7 days.

FIGURE 12

Cell proliferation on PCL and S-PCL stents compared to PBS control.