title: Material- and feature-dependent effects on cell adhesion to micro injection moulded medical polymers.
abstract: Two polymers, polymethylmethacrylate (PMMA) and cyclic olefin copolymer (COC), containing a range of nano- to micron- roughness surfaces (Ra 0.01, 0.1, 0.4, 1.0, 2.0, 3.2 and 5.0μm) were fabricated using electrical discharge machining (EDM) and replicated using micro injection moulding (μIM). Polymer samples were characterized using optical profilometry, atomic force microscopy (AFM) and water surface contact angle. Cell adhesion tests were carried out using bacterial Pseudomonas fluorescens and mammalian Madin-Darby Canine Kidney (MDCK) cells to determine the effect of surface hydrophobicity, surface roughness and stiffness. It is found that there are features which gave insignificant differences (feature-dependent effect) in cell adhesion, albeit a significant difference in the physicochemical properties (material-dependent effect) of substrata. In bacterial cell adhesion, the strongest feature-dependence is found at Ra 0.4μm surfaces, with material-dependent effects strongest at Ra 0.01μm. Ra 0.1μm surfaces exhibited strongest feature-dependent effects and Ra 5.0μm has strongest material-dependent effects on mammalian cell adhesion. Bacterial cell adhesion is found to be favourable to hydrophobic surfaces (COC), with the lowest adhesion at Ra 0.4μm for both materials. Mammalian cell adhesion is lowest in Ra 0.1μm and highest in Ra 1.0μm, and generally favours hydrophilic surfaces (PMMA). These findings can be used as a basis for developing medical implants or microfluidic devices using micro injection moulding for diagnostic purposes, by tuning the cell adhesion on different areas containing different surface roughnesses on the diagnostic microfluidic devices or medical implants.
authors.affiliation: University College Dublin, College of Engineering and Architecture, School of Mechanical and Materials Engineering, Ireland.
authors.forename: Seong Ying
authors.initials: SY
authors.lastname: Choi
authors.affiliation: University College Dublin, College of Engineering and Architecture, School of Chemical and Bioprocess Engineering, Ireland.
authors.forename: Olivier
authors.initials: O
authors.lastname: Habimana
authors.affiliation: University College Dublin, College of Science, School of Biology and Environmental Science, Ireland.
authors.forename: Peter
authors.initials: P
authors.lastname: Flood
authors.affiliation: University College Dublin, College of Science, School of Biology and Environmental Science, Ireland.
authors.forename: Emmanuel G
authors.initials: EG
authors.lastname: Reynaud
authors.affiliation: University College Dublin, School of Physics and Conway Institute of Biomolecular and Biomedical Research, Ireland.
authors.forename: Brian J
authors.initials: BJ
authors.lastname: Rodriguez
authors.affiliation: University College Dublin, College of Engineering and Architecture, School of Mechanical and Materials Engineering, Ireland.
authors.forename: Nan
authors.initials: N
authors.lastname: Zhang
authors.affiliation: University College Dublin, College of Engineering and Architecture, School of Chemical and Bioprocess Engineering, Ireland.
authors.forename: Eoin
authors.initials: E
authors.lastname: Casey
authors.affiliation: University College Dublin, College of Engineering and Architecture, School of Mechanical and Materials Engineering, Ireland. Electronic address: michael.gilchrist@ucd.ie.
authors.forename: Michael D
authors.initials: MD
authors.lastname: Gilchrist
mesh_terms: D000818:Animals; D001422:Bacterial Adhesion / Q000187:drug effects; D002448:Cell Adhesion / Q000187:drug effects; D002460:Cell Line; D004285:Dogs; D057927:Hydrophobic and Hydrophilic Interactions; D018625:Microscopy, Atomic Force; D011108:Polymers / Q000737:chemistry* / Q000494:pharmacology; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011551:Pseudomonas fluorescens / Q000187:drug effects / Q000502:physiology; D013499:Surface Properties
chemical_list: D011108:Polymers; D019904:Polymethyl Methacrylate
keywords: Cyclic olefin copolymer (COC); Interface; Madin-Darby Canine Kidney (MDCK) cells; Polymethylmethacrylate (PMMA); Pseudomonas fluorescens; Surface topography