The Construction of Alkaline Phosphatase‐Responsive Biomaterial and Its Application for In Vivo Urinary Tract Infection Therapy

Urinary tract infections caused by urinary catheter implantations are becoming more serious. Therefore, the construction of a responsive antibacterial biomaterial that can not only provide biocompatible conditions, but also effectively prevent the growth and metabolism of bacteria, is urgently needed. In this work, a benzophenone‐derived phosphatase light‐triggered antibacterial agent is designed and synthesized, which is tethered to the biological materials using a one‐step method for in vivo antibacterial therapy. This surface could kill gram‐positive bacteria (Staphylococcus aureus) and gram‐negative bacteria (Escherichia coli). More importantly, because this material exhibited a zwitterion structure, it does not damage blood cells and tissue cells. When the bacteria interact with this surface, the initial fouling of the bacteria is reduced by zwitterion hydration. When the bacteria actively accumulate and metabolize to produce a certain amount of alkaline phosphatase, the surface immediately started the sterilization performance, and the bactericidal effect is achieved by destroying the bacterial cell membrane. In summary, an antibacterial biomaterial that shows biocompatibility with mammalian cells is successfully constructed, providing new ideas for the development of intelligent urinary catheters. A simple process is designed to prepare a biocompatible antibacterial surface, which can inhibit the initial adhesion of bacteria and can convert to bactericidal surface once bacteria breed, since alkaline phosphatases secreted by the bacteria cut off phosphate structures. Moreover, an antibacterial model in the bladder of a rabbit is built, which lays a foundation for the clinical application.