3D printed polycaprolactone/poly (L-lactide-co-ϵ-caprolactone) composite ureteral stent with biodegradable and antibacterial properties

The clinical application of biodegradable ureteral stents holds significant potential. There is an urgent need to develop new materials for ureteral stents to address the limitations related to performance degradation and antibacterial properties observed in current designs. Here, we developed a Polycaprolactone (PCL)/Poly (L-lactide-co-& varepsilon;-caprolactone) (PLCL) composite ureteral stent by three-dimensional (3D) printing, which exhibits biodegradable and antibacterial properties. Silver nanoparticles (AgNPs) were bonded to the surface of the stent through the polymerization of dopamine (PDA) and coating with type I collagen (Col I). The ureteral stent (PP-PDA-Ag-Col) had a densely spiraled structure and higher hydrophilicity. The release behavior of silver ions from the stent was found to be slow and continuous when coated with AgNPs, which can enable long-term antibacterial effects after being implanted in vivo. Additionally, in vitro degradation experiments demonstrated that the different ratios of ureteral stents degraded slowly in artificial urine over 6 weeks without compromising functionality. The stent exhibits excellent hemocompatibility and cell compatibility. The subcutaneous implantation experiment in Sprague-Dawley rats showed that the PP-PDA-Ag-Col stent degraded slowly in vivo and had good biocompatibility. The stent PCL5/PLCL5 was the most promising ureteral stent regarding antibacterial, mechanical properties, and degradation. The novel 3D-printed PP-PDA-Ag-Col stent exhibits biocompatibility for safe in vivo transplantation and antibacterial properties that reduce reliance on antibiotics. Additionally, its biodegradability eliminates the need for secondary surgical removal, making it a promising option for the clinical application of ureteral stents.