Citrate-Eluting Braided-Electrospinning Degradable Polyurethane Stents for Enhanced Drainage and Anti-Encrustation

Ureteral stents are essential for postoperative management of ureterostenosis but often cause complications due to their nondegradable nature and propensity for encrustation. This study develops a biodegradable composite stent integrating a braided polycaprolactone (PCL)/polylactide (PLA) stent with an electrospinning degradable polyurethane (DPU) membrane loaded with potassium sodium hydrogen citrate (PSHC). Thermal treatment of the PCL/PLA stent induces melt-bonding, forming a film that enhances the radial compressive resistance. Subsequent electrospinning of DPU further improves the compressive resistance and hydrophilicity. The resulting DPU fibrous membrane composite braided ureteral stent (PFBUS) exhibits superior urinary drainage with a 30-fold higher flow rate at 50% compression versus commercial PU stents. Incorporation of PSHC conferred anti-encrustation properties through localized drug release. Comprehensive in vitro and in vivo evaluations confirmed the biocompatibility. This multifunctional design simultaneously addresses mechanical integrity, drainage optimization, and sustained anti-encrustation within a fully biodegradable platform, eliminating secondary removal surgery and advancing clinical ureteral stent applications.