Regulating Supramolecular Assembly and Disassembly of Chitosan toward Efficiently Antibacterial Lubricous and Biodegradable Hydrogel Urinary Catheters

Urinary catheters serve as critical medical devices in clinical practice. However, the currently used urinary catheters lack efficient antibacterial and lubricating properties, often leading to discomfort with patients and even severe urinary infections. Herein, a new strategy of supramolecular assembly and disassembly of chitosan (Cs) is developed that enables efficient antibacterial lubricous and biodegradable hydrogel urinary catheters. Sodium lauryl sulfonate (SLS) is employed to induce supramolecular assembly on the surface of Cs film strips in an aqueous solution, resulting in the formation of hollow hydrogel catheters of Cs@SLS. Subsequent disassembly in a strong alkaline solution eliminates the SLS component, yielding neat Cs hydrogel catheters. The mechanical strength of these catheters reaches 16 MPa, exceeding that of similar devices made of plastics. The Cs hydrogel catheters are endowed with high antibacterial activity, capable of inhibiting the growth of Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and Proteus mirabilis(P. mirabilis) on its surface, while these bacteria are found to proliferate rapidly on plastic catheters within 24 h. They also demonstrate excellent lubricity, with a friction coefficient approaching zero, and thus about 13 times lower than that of plastic catheters. In vivo tests further confirm the biodegradability of the catheters, highlighting their strong potential for clinical applications.