Interfacial energy-mediated stability of liquid barrier for sustainable and efficient anti-clogging of urinary catheter

Abstract

Catheter clogging by crystal biofilm always causes enormous economic burden and serious consequences. However, most researches mainly focus on anti-bacteria while neglecting the deposition of stone, which often protects encapsulated bacteria and accelerates catheter clogging. Inspired by Nepenthes pitcher, we herein present a bioinspired liquid barrier-infused coating (BLBC) with synergistically suppressing deposition of stone and bacteria, displaying a sustainable and effective anti-clogging capability. Taking infused ionic liquids (ILs) as the liquid barrier, the inhibition of stone deposition comes from reducing mineral nucleation and interfacial adhesion. Compared with traditional PVC, the BLBC shows excellent and universal anti-stone ability, displaying ca. 96.4 % reduction for CaCO₃ and ca. 96.2 % reduction for CaSO₄. Because Ca₃(PO₄)₂ always exists in the form of flocculent precipitation with low adhesion on most substrates, a high anti-stone result (ca. 44.5 % reduction) for Ca₃(PO₄)₂ can be kept. Moreover, the experiments and DFT results reveal that enhancing IL-substrate affinity and attenuating IL dissolution endows the BLBCs with the sustainable stability of IL layer, and subsequent the durability of anti-stone and anti-bacteria. Compared with commercial urinary catheter, the BLBC extends anti-crystal biofilm from one to five days in vitro model of flow cells, displaying a significant reduction for two main clogging minerals (i.e., ca. 97.7 % for Mg(NH₄)PO₄ and 89.9 % for Ca₃(PO₄)₂). Therefore, this study may provide a promising tactic to avert the clogging problem of urinary catheter.