title: Protein adsorption mechanisms determine the efficiency of thermally controlled cell adhesion on poly(N-isopropyl acrylamide) brushes.
abstract: This study investigated the impact of the protein adsorption mechanism(s) on the efficiency of thermally controlled cell adhesion and release from poly(N-isopropyl acrylamide) brushes. Large format polymer gradients were used to screen for grafting densities and substrate chemistries that alter both cell adhesion at 37 °C and rapid cell release at 25 °C. In particular, the grafting conditions investigated allowed protein adsorption to the underlying substrate, penetration of the brush only, or adsorption to the outer edge of the film. At an average molecular weight of 30 kDa (degree of polymerization N ∼ 270), the results show that robust protein adsorption to polymer brushes impairs rapid cell release below the lower critical solution temperature. Conversely, grafting conditions that permit protein penetration of the brush but block strong adsorption to the underlying substrate support cell adhesion above the transition temperature and ensure efficient cell recovery at lower temperature. These findings demonstrate the impact of protein adsorption mechanisms, surface chemistry, and polymer properties on thermally controlled cell capture and release.
authors.affiliation: Department of Chemical and Biomolecular Engineering, University of Illinois, 600 Mathews Avenue, Urbana, IL 61801, USA.
authors.forename: Sangwook
authors.initials: S
authors.lastname: Choi
authors.forename: Byung-Chan
authors.initials: BC
authors.lastname: Choi
authors.forename: Changying
authors.initials: C
authors.lastname: Xue
authors.forename: Deborah
authors.initials: D
authors.lastname: Leckband
mesh_terms: D000178:Acrylamides / Q000737:chemistry* / Q000378:metabolism; D000180:Acrylic Resins; D000327:Adsorption / Q000502:physiology; D000818:Animals; D002448:Cell Adhesion / Q000502:physiology; D006358:Hot Temperature; D051379:Mice; D041681:NIH 3T3 Cells; D011108:Polymers / Q000737:chemistry* / Q000378:metabolism; D011506:Proteins / Q000737:chemistry* / Q000378:metabolism
chemical_list: D000178:Acrylamides; D000180:Acrylic Resins; D011108:Polymers; D011506:Proteins; C052970:poly-N-isopropylacrylamide