Preparation of Dipyridamole/Polyurethane Core–Shell Nanofibers by Coaxial Electrospinning for Controlled-Release Antiplatelet Application

Abstract

To improve the hemocompatibility of blood-compatible materials, antiplatelet drug dipyridamole (DIP) was encapsulated in polyurethane (PU) to form core-shell nanofibers by coaxial electrospinning method. PU solution and DIP/polycaprolactone compound solution served as shell and core fluid, respectively. Uniform fibers without beads, were fabricated and a clear core-shell structure was generated. The diameter of nanofibers and core structure increased with an increase in the flow rate of the core solution. X-Ray diffraction and differential scanning calorimeter showed that the whole system formed solid dispersion and DIP was dispersed in polymer matrix in an amorphous state. In vitro drug release test demonstrated that releasing curve had two phases consisting of initial burst release and sustained release governed by diffusion mechanism. A more flat curve occurred when the diameter of PU shell increased. In this case, the PU shell served as a barrier restricted DIP release from core drug reservoir. In vitro platelet adhesion test demonstrated that the DIP had maintained its antiplatelet effect after coaxial electrospinning process and could present distinguished antiplatelet activity after 7th and 30th days. Finally, DIP loaded core-shell nanofiber mats with good hemocompatibility, were conveniently fabricated by coaxial electrospinning, which has great potential in the field of tissue engineering vascular graft.

Fabrication and Characterization of Flexible Medical-Grade TPU Filament for Fused Deposition Modeling 3DP Technology

“…Tensile strength of injection-molded S-TPU samples was 26 ± 2 MPa, which was close to values determined for commercially available medical-grade PURs, like Carbothane ® (39–67 MPa) and Desmopan ® (25–50 MPa) [47,48,49,50,51], as well in the range of elastic TPU filament NinjaFlex ® (26 MPa) [52]. Noted elongation at the break of obtained S-TPUs was of 706 ± 29% and higher than Tecoflex ® (365 ± 25%–400 ± 38% [53,54], the medical-grade PUR for biomedical applications and NinjaFlex ® filament (660%) [52].…”

3D-printed Bioresorbable Stent Coated with Dipyridamole-Loaded Nanofiber for Restenosis Prevention and Endothelialization

“…[ 21 ] developed a nanofibrous scaffold with a higher DP content (10%), which inhibited SMC proliferation and showed no adverse effect on endothelial cells. A similar concentration of DP in the solution was also used to prepare drug-loaded nanofibers to achieve the antiplatelet effect[ 28 , 29 ]. Here, DP was dissolved in PDLLA/HFIP solution at a concentration of 10% to PDLLA.…”

Preparation and Characterization of Porous Core-Shell Fibers for Slow Release of Tea Polyphenols

“…Drugs can be encapsulated into the core phase by using this technique. With increased efficiency and encapsulation rate, the burst release can be reduced, and drug bioactivity can be protected [ 2 , 3 ]. The current method may find wide applications for controlled release of proteins and tissue [ 4 ].…”