Tuning the density of poly(ethylene glycol) chains to control mammalian cell and bacterial attachment

Ahmed Al-Ani, Hitesh Pingle, Nicholas P. Reynolds, Peng Yuan Wang, Peter Kingshott

Research output: Contribution to journalArticle

5 Citations (Scopus)

Abstract

Surface modification of biomaterials with polymer chains has attracted great attention because of their ability to control biointerfacial interactions such as protein adsorption, cell attachment and bacterial biofilm formation. The aim of this study was to control the immobilisation of biomolecules on silicon wafers using poly(ethylene glycol)(PEG) chains by a “grafting to” technique. In particular, to control the polymer chain graft density in order to capture proteins and preserve their activity in cell culture as well as find the optimal density that would totally prevent bacterial attachment. The PEG graft density was varied by changing the polymer solubility using an increasing salt concentration. The silicon substrates were initially modified with aminopropyl-triethoxysilane (APTES), where the surface density of amine groups was optimised using different concentrations. The results showed under specific conditions, the PEG density was highest with grafting under “cloud point” conditions. The modified surfaces were characterised with X-ray photoelectron spectroscopy (XPS), ellipsometry, atomic force microscopy (AFM) and water contact angle measurements. In addition, all modified surfaces were tested with protein solutions and in cell (mesenchymal stem cells and MG63 osteoblast-like cells) and bacterial (Pseudomonas aeruginosa) attachment assays. Overall, the lowest protein adsorption was observed on the highest polymer graft density, bacterial adhesion was very low on all modified surfaces, and it can be seen that the attachment of mammalian cells gradually increased as the PEG grafting density decreased, reaching the maximum attachment at medium PEG densities. The results demonstrate that, at certain PEG surface coverages, mammalian cell attachment can be tuned with the potential to optimise their behaviour with controlled serum protein adsorption.

Original languageEnglish
Article number343
JournalPolymers
Volume9
Issue number8
DOIs
Publication statusPublished - Aug 5 2017
Externally publishedYes

Fingerprint

Polyethylene glycols
Tuning
Cells
Proteins
Polymers
Adsorption
Grafts
Graft copolymers
Osteoblasts
Ellipsometry
Biofilms
Biocompatible Materials
Biomolecules
Silicon
Angle measurement
Stem cells
Silicon wafers
Cell culture
Biomaterials
Contact angle

Keywords

  • Biofilm formation
  • Cell attachment
  • PEG
  • Protein adsorption
  • Surface modification

ASJC Scopus subject areas

  • Chemistry(all)
  • Polymers and Plastics

Cite this

Tuning the density of poly(ethylene glycol) chains to control mammalian cell and bacterial attachment. / Al-Ani, Ahmed; Pingle, Hitesh; Reynolds, Nicholas P.; Wang, Peng Yuan; Kingshott, Peter.

In: Polymers, Vol. 9, No. 8, 343, 05.08.2017.

Research output: Contribution to journalArticle

Al-Ani, Ahmed ; Pingle, Hitesh ; Reynolds, Nicholas P. ; Wang, Peng Yuan ; Kingshott, Peter. / Tuning the density of poly(ethylene glycol) chains to control mammalian cell and bacterial attachment. In: Polymers. 2017 ; Vol. 9, No. 8.
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