Rational Design of Polyphosphorylcholine‐Based Micelles for Superior Anti‐Biofilm Activity

Abstract

AbstractIt's a great challenge to completely eradicate the bacteria in biofilms by antimicrobials, since the cells are wrapped in the dense extracellular polymeric substances. Herein, in order to deliver antibacterial agents into staphylococcal biofilms and to kill the bacteria in the biofilms, an amphiphilic polymer with tertiary amine groups, poly(2‐methacryloyloyethyl phosphorylcholine)‐b‐poly {α‐[4‐(diethylamino)methyl‐1,2,3‐triazol]‐caprolactone‐co‐caprolactone} (PMPC‐PDCL) is synthesized, and its micelles are used as carriers for a model antimicrobial triclosan (TCS) to research the effect of polymeric components on antibiofilm. Polycaprolactone‐b‐poly(2‐methacryloyloxyethyl phosphorylcholine) (PMPC‐PCL) and poly(ethylene glycol)‐b‐polycaprolactone (PEG‐PCL) are designed as contrast materials. The results demonstrate that PMPC‐PDCL micelles possess the highest drug loading, and the accumulative TCS release rate of PMPC‐PDCL/TCS micelles at pH 5.5+lipase is highest. The minimum bactericidal concentration value of PMPC‐PDCL/TCS micelles is 64 µg mL−1. According to the confocal laser scanning microscopy, the penetration effect of PMPC‐PDCL micelles is the best, followed by PMPC‐PCL and PEG‐PCL micelles. PMPC‐PDCL/TCS micelles display excellent anti‐biofilm both on account of their outstanding penetration effect and drug release behavior in acidic and lipase environments. Thus, PMPC‐PDCL micelles can be used as carriers to deliver the antibacterial agents into biofilms, which has important significance to cure diseases caused by bacterial infection.