Preparation and property evaluation of biodegradable elastomeric PTMC/PLCL networks used as ureteral stents

Abstract

Ureteral stents have a wide range of applications in urology. In this study, we aimed to prepare poly(1,3-trimethylene carbonate)/poly(L-lactide-co-ε-caprolactone) (PTMC/PLCL) networks with pentaerythritol triacrylate (PETA) as a crosslinking agent by gamma irradiation under vacuum to resist creep, improve shape stability and prevent the migration of stent tube. 1H and 13C NMR spectra showed that PTMC and PLCL were successfully synthesized. FTIR indicated that the PTMC/PLCL networks were successfully prepared. Both the PLCL content and the irradiation dose had an effect on the degree of crosslinking. The gel fraction of the networks increased first and then decreased. The optimized conditions for cross-linking were 20% PLCL and at a standard sterilization dose of 25 kGy. The PTMC/PLCL(80/20) network had a gel fraction of 92.5%, a tensile strength of 32.7 MPa, and a tensile set value as low as 5%. Meanwhile, the cross-linking behavior followed the Chen-Liu-Tang equation rather than the Charlesby-Pinner equation. Porcine pancreatic lipase effectively accelerated the degradation of the network in vitro. Cytotoxicity analysis showed that the PTMC/PLCL network containing PETA had no adverse effects on the growth and proliferation of cells. Therefore, the inherent biocompatibility and biodegradability, good flexibility and elasticity, and neither migration nor early fracture allowed the PTMC/PLCL network to be used as a ureteral stent.