Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
600313 | Colloids and Surfaces B: Biointerfaces | 2013 | 10 Pages |
Various thermo-responsive polymeric surfaces were evaluated in terms of cell adhesion/detachment and surface analysis. Three kinds of thermo-responsive poly(N-isopropylacrylamide) (PIPAAm) surfaces were prepared by an electron beam irradiation (PIPAAm-EB), a reversible addition fragmentation polymerization (PIPAAm-RAFT), and a redox polymerization (PIPAAm-Redox). Although cell adhesion and detachment on surfaces of PIPAAm-EB and PIPAAm-RAFT were able to be modulated by altering their surface characters with changing the amounts of polymers, the adhesion and detachment were hardly controlled on PIPAAm-Redox surfaces, even though the amounts of polymers on the surface were able to be modulated. Atomic force microscopy (AFM) probed the interactions between AFM tip and the polymeric surface for further investigating a different conformation of polymeric surface. The modification of AFM tip surface coated with octadecyltrichlorosilane was found to change the interaction between the thermo-responsive surface and the tip. Adhesion force analysis clearly showed changes in the hydrophilic/hydrophobic characters of three kinds of thermo-responsive surfaces immediately after a change in temperature. From the kinetics study of AFM, PIPAAm-EB and PIPAAm-RAFT surfaces became hydrophilic less than 30 min after temperature decrease, but PIPAAm-Redox surfaces required 120 min to become hydrophilic after temperature reduction. These results indicated that a faster conformational change triggered cell detachment and a slow conformation change hardly affected cell detachment. Therefore, polymeric conformation on solid substrate was an important factor for modulating cell adhesion and detachment.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► We synthesize various thermo-responsive surfaces. ► We examine cell adhesion and detachment on thermo-responsive surfaces. ► We evaluate the property of thermo-responsive surfaces by atomic force microscopy. ► The cell detachment strongly depends on the conformation of surface.