title: Phosphorylcholine-containing polyurethanes for the control of protein adsorption and cell attachment via photoimmobilized laminin oligopeptides.
abstract: In this study, we synthesized a biomaterial whose surface inhibits non-specific protein and cell attachment. The polymer was designed to mimic the external cell plasma membrane properties through the introduction of particular chemical constituents of the cell membrane: phospholipid polar headgroups. This was done by copolymerizing phosphorylcholine (PC) groups into a polyurethane polymer backbone (PCPUR). Peptides known to induce specific cell attachment were subsequently bound to the surface of this copolymer in a photoadressible manner to obtain surfaces that allowed the attachment of cells in a specific pattern. Two polymers with different phosphorylcholine concentrations were synthesized and their bulk and surface properties were characterized through differential scanning calorimetry, wettability measurements, angle-resolved X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry. Protein and lipid adsorption investigation using optical waveguide light mode spectroscopy showed that the irreversible adsorption of both proteins and lipids is drastically reduced as a result of simultaneous contributions of the PC groups, molecular mobility and strong hydrophilicity of the polymers. Consequently, this leads to a marked reduction in the cellular attachment response, which further decreases with increasing PC concentration. Finally, when the polymer surface was photo-derivatized, attachment of the neural NG108-15 cell line occurred only on the areas of the PCPUR where the laminin CDPGYIGSR peptide sequence was photoimmobilized. Cell attachment was nevertheless found to be non-specific with respect to the peptide sequence used and reasons for such results are therefore discussed.
authors.affiliation: Laboratory for Surface Science and Technology, Swiss Federal Institute of Technology Zürich.
authors.forename: L
authors.initials: L
authors.lastname: Ruiz
authors.forename: E
authors.initials: E
authors.lastname: Fine
authors.forename: J
authors.initials: J
authors.lastname: Vörös
authors.forename: S A
authors.initials: SA
authors.lastname: Makohliso
authors.forename: D
authors.initials: D
authors.lastname: Léonard
authors.forename: D S
authors.initials: DS
authors.lastname: Johnston
authors.forename: M
authors.initials: M
authors.lastname: Textor
authors.forename: H J
authors.initials: HJ
authors.lastname: Mathieu
mesh_terms: D000327:Adsorption; D000595:Amino Acid Sequence; D000818:Animals; D001672:Biocompatible Materials / Q000138:chemical synthesis* / Q000737:chemistry*; D002417:Cattle; D002448:Cell Adhesion; D002460:Cell Line; D006801:Humans; D066298:In Vitro Techniques; D007797:Laminin / Q000138:chemical synthesis / Q000737:chemistry; D050356:Lipid Metabolism; D008422:Materials Testing; D051379:Mice; D009842:Oligopeptides / Q000138:chemical synthesis / Q000737:chemistry; D010767:Phosphorylcholine / Q000138:chemical synthesis / Q000737:chemistry; D011140:Polyurethanes / Q000138:chemical synthesis* / Q000737:chemistry*; D011506:Proteins / Q000378:metabolism*; D051381:Rats; D013499:Surface Properties
chemical_list: D001672:Biocompatible Materials; D007797:Laminin; D009842:Oligopeptides; D011140:Polyurethanes; D011506:Proteins; D010767:Phosphorylcholine