Protein, cell and bacterial response to atmospheric pressure plasma grafted hyaluronic acid on poly(methylmethacrylate)
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Hyaluronic acid (HA) has been immobilised on poly(methyl methacrylate) (PMMA) surfaces using a novel dielectric barrier discharge (DBD) plasma process for the purposes of repelling protein, cellular and bacterial adhesion in the context of improving the performance of ophthalmic devices. Grafting was achieved by the following steps: (1) treatment of the PMMA with a DBD plasma operating at atmospheric pressure, (2) amine functionalisation of the activated polymer surface by exposure to a 3-aminopropyltrimethoxysilane (APTMS) linker molecule and (3) reaction of HA with the surface bound amine. The mechanism and effectiveness of the grafting process was verified by surface analysis. XPS data indicates that the APTMS linker molecule binds to PMMA via the Si–O chemistry and has the required pendant amine moiety. The carboxylic acid moiety on HA then binds with this –NH2 group via standard carbodiimide chemistry. ToF-SIMS confirms the presence of a coherent HA layer the microstructure of which is verified by AFM. The plasma grafted HA coating surfaces showed a pronounced decrease in protein and cellular adhesion when tested with bovine serum albumin and human corneal epithelial cells, respectively. The ability of these coatings to resist bacterial adhesion was established using Staphylococcus aureus NTC8325. Interestingly, the coatings did not repel bacterial adhesion, indicating that the mechanism of adhesion of bacterial cells is different to that for the surface interactions of mammalian cells. It is proposed that this difference is a consequence of the specific HA conformation that occurs under the conditions employed here. Hence, it is apparent that the microstructure/architecture of the HA coatings is an important factor in fabricating surfaces intended to repel proteins, mammalian and bacterial cells.
KeywordsPMMA Hyaluronic Acid Dielectric Barrier Discharge Bacterial Adhesion Dielectric Barrier Discharge Plasma
The authors wish to thank Professor Rachel Williams, University of Liverpool for the provision of the corneal epithelial cell line (Dr. K. Araki-Sasaki’s Kagoshima, Japan). Financial support from the Department for Employment and Learning, Northern Ireland under the Cross Border Research and Development Funding Programme - Strengthening the All-island Research Base for Functional Biomaterials (DEL-UU-05) is acknowledged.
- 10.D’Sa RA, Burke GA, Meenan BJ. Lens epithelial cell response to atmospheric pressure plasma modified poly (methylmethacrylate) surfaces. J Mater Sci. 2010;21(5):1703–12.Google Scholar
- 13.Laurent TC, Fraser JR. Hyaluronan. FASEB J. 1992;6(7):2397–404.Google Scholar
- 14.Fraser JR, Laurent TC. Hyaluronan. In: Comper WD, editor. Extracellular matrix, vol. 2., Molecular Components and Interactions. Amsterdam: Harwood Academic Publishers; 1996. p. 141–99.Google Scholar
- 15.Laurent TC. Structure of hyaluronic acid. In: Balasz E, editor. Chemistry and molecular biology of the intracellular matrix. London: Academic Press; 1970. p. 709–32.Google Scholar
- 28.Cui N-Y, Upadhyay DJ, Anderson CA, Meenan BJ, Brown NM. Surface oxidation of a Melinex 800 PET polymer material modified by an atmospheric dielectric barrier discharge studied using X-ray photoelectron spectroscopy and contact angle measurement. Appl Surf Sci. 2007;253(8):3865–71.CrossRefGoogle Scholar
- 30.Chastain J. Handbook of X-ray photoelectron spectroscopy. Minnesota: Perkin-Elmer Corporation; 1992.Google Scholar
- 31.Araki-Sasaki K, Ohashi Y, Sasabe T, Hayashi K, Watanabe H, Tano Y, et al. An SV40-immortalized human corneal epithelial cell line and its characterization. IOVS. 1995;36(3):614–21.Google Scholar
- 35.Bierbaum K, Kinzler M, Wöll C, Grunze M, Hähner G, Heid S, et al. A near edge X-ray absorption fine structure spectroscopy and X-ray photoelectron spectroscopy study of the film properties of self-assembled monolayers of organosilanes on oxidized Si (100). Langmuir. 1995;11(2):512–8.CrossRefGoogle Scholar