Slippery dopamine–fluoropolymer hybrid surface for improving biliary stent longevity

Biliary obstruction leads to bile retention and triggers a cascade of pathological events. Bile accumulation induces cholestasis and inflammation, progressing to hepatocellular injury, fibrosis, and ultimately liver failure. To restore bile flow, biliary stents are a necessary option due to their immediate patency. However, their high susceptibility to foreign body reaction (FBR) associated fibrosis, biofilm formation, and biliary sludge accumulation leads to frequent occlusion. To address this limitation, we developed the Enhanced Longevity by anti-fouling Functional coating for Stent (ELFS), a lubricant-infused coating that prevents stent occlusion. ELFS can be readily fabricated via a simple dip-coating solution process and employ a polydopamine (PDA) adhesion layer. Intravital imaging in mice confirmed that ELFS suppressed the FBR by blocking early neutrophil adhesion, which in turn prevented downstream immune-fibrotic cascades. At 3 h, neutrophil recruitment in the non-coated group was >20-fold higher than in ELFS-coated groups. Additionally, ELFS-coated stents remained free of biofilm for over six months in mice and maintained full open for two months in a rabbit common bile duct model. In contrast, non-coated stents resulted in complete occlusion, bile duct dilation (over 4 times), hepatomegaly (over 2 times), and fibrosis.