Antibacterial modification of an injectable, biodegradable, non-cytotoxic block copolymer-based physical gel with body temperature-stimulated sol-gel transition and controlled drug release

Xiaowen Wang, Huawen Hu, Wenyi Wang, Ka I. Lee, Chang Gao, Liang He, Yuanfeng Wang, Chuilin Lai, Bin Fei, John Haozhong Xin

Research output: Journal article publicationJournal articleAcademic researchpeer-review

10 Citations (Scopus)

Abstract

Biomaterials are being extensively used in various biomedical fields; however, they are readily infected with microorganisms, thus posing a serious threat to the public health care. We herein presented a facile route to the antibacterial modification of an important A-B-A type biomaterial using poly (ethylene glycol) methyl ether (mPEG)- poly(ε-caprolactone) (PCL)-mPEG as a typical model. Inexpensive, commercial bis(2-hydroxyethyl) methylammonium chloride (DMA) was adopted as an antibacterial unit. The effective synthesis of the antibacterial copolymer mPEG-PCL-~~~-PCL-mPEG (where ~~~ denotes the segment with DMA units) was well confirmed by FTIR and1H NMR spectra. At an appropriate modification extent, the DMA unit could render the copolymer mPEG-PCL-~~~-PCL-mPEG highly antibacterial, but did not largely alter its fascinating intrinsic properties including the thermosensitivity (e.g., the body temperature-induced sol-gel transition), non-cytotoxicity, and controlled drug release. A detailed study on the sol-gel-sol transition behavior of different copolymers showed that an appropriate extent of modification with DMA retained a sol-gel-sol transition, despite the fact that a too high extent caused a loss of sol-gel-sol transition. The hydrophilic and hydrophobic balance between mPEG and PCL was most likely broken upon a high extent of quaternization due to a large disturbance effect of DMA units at a large quantity (as evidenced by the heavily depressed PCL segment crystallinity), and thus the micelle aggregation mechanism for the gel formation could not work anymore, along with the loss of the thermosensitivity. The work presented here is highly expected to be generalized for synthesis of various block copolymers with immunity to microorganisms. Light may also be shed on understanding the phase transition behavior of various multiblock copolymers.
Original languageEnglish
Pages (from-to)342-351
Number of pages10
JournalColloids and Surfaces B: Biointerfaces
Volume143
DOIs
Publication statusPublished - 1 Jul 2016

Keywords

  • Amphiphilic balance
  • Antibacterial modification
  • Crystallinity
  • MPEG-PCL-DMA-PCL-mPEG block copolymers
  • Sol-gel-sol transition

ASJC Scopus subject areas

  • Biotechnology
  • Surfaces and Interfaces
  • Physical and Theoretical Chemistry
  • Colloid and Surface Chemistry

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