Silk fibroin/dual drugs eluting polydioxanone monofilament braided ureteral stent with antibacterial and anti-stenotic functions.

Placement of ureteral stents is an effective method for treating ureteral stricture clinically. Long-term placement leads to calcium salt deposition, stones and infection issues. Hence, development of ureteral stents with antibacterial and anti-stenosis functions is of great significance. In this work, polydioxanone (PDO) monofilament was braided into a tubular stent and then coated with silk fibroin (SF) microspheres loading of rapamycin (RAPA) and paclitaxel (PTX), subsequently, SF-loaded moxifloxacin (MFX) film with a biomimetic lotus leaf structure was formed onto the inner layer of the stent, to obtain a composite ureteral stent with antibacterial and anti-stenosis functions. In vitro drug release studies revealed that RAPA and PTX exhibited a sustained release up to 168 h with the cumulative release rates of RAPA and PTX at 40.36 % and 38.21 %, respectively. The lotus leaf-structured SF film exhibited a micro-nano structure and a hydrophobic "lotus leaf effect". The biocompatibility and anti-fibroblast properties were evaluated in vitro and in vivo. A rat bladder model was selected to verify the anti-encrustation properties of the ureteral stent. The developed ureteral stent possesses fair biocompatibility, anti-fibrotic and anti-encrustation properties (p < 0.05), provides a potential application as a novel antibacterial and anti-stenotic stent in the treatment of ureteral stenosis.