TY - JOUR
T1 - Modulation of graft architectures for enhancing hydrophobic interaction of biomolecules with thermoresponsive polymer-grafted surfaces
AU - Idota, Naokazu
AU - Kikuchi, Akihiko
AU - Kobayashi, Jun
AU - Sakai, Kiyotaka
AU - Okano, Teruo
PY - 2012/11/1
Y1 - 2012/11/1
N2 - This paper describes the effects of graft architecture of poly(N-isopropylacrylamide) (PIPAAm) brush surfaces on thermoresponsive aqueous wettability changes and the temperature-dependent hydrophobic interaction of steroids in silica capillaries (I.D.: 50 μm). PIPAAm brushes were grafted onto glass substrates by surface-initiated atom transfer radical polymerization (ATRP) that is one of the living radical polymerization techniques. Increases in the graft density and chain length of PIPAAm brushes increased the hydration of polymer brushes, resulting in the increased hydrophilic properties of the surface below the transition temperature of PIPAAm at 32 °C. More hydrophobic surface properties were also observed on surfaces modified with the block copolymers of IPAAm and n-butyl methacrylate (BMA) than that with IPAAm homopolymer-grafted surfaces over the transition temperature. Using PBMA-b-PIPAAm-grafted silica capillaries, the baseline separation of steroids was successfully achieved by only changing temperature. The incorporation of hydrophobic PBMA chains in grafted PIPAAm enhanced the hydrophobic interaction with testosterone above the transition temperature. The surface modification of hydrophobicity-enhanced thermoresponsive polymers is a promising method for the preparation of thermoresponsive biointerfaces that can effectively modulated their biomolecule and cell adsorption with the wide dynamic range of hydrophilic/hydrophobic property change across the transition temperature.
AB - This paper describes the effects of graft architecture of poly(N-isopropylacrylamide) (PIPAAm) brush surfaces on thermoresponsive aqueous wettability changes and the temperature-dependent hydrophobic interaction of steroids in silica capillaries (I.D.: 50 μm). PIPAAm brushes were grafted onto glass substrates by surface-initiated atom transfer radical polymerization (ATRP) that is one of the living radical polymerization techniques. Increases in the graft density and chain length of PIPAAm brushes increased the hydration of polymer brushes, resulting in the increased hydrophilic properties of the surface below the transition temperature of PIPAAm at 32 °C. More hydrophobic surface properties were also observed on surfaces modified with the block copolymers of IPAAm and n-butyl methacrylate (BMA) than that with IPAAm homopolymer-grafted surfaces over the transition temperature. Using PBMA-b-PIPAAm-grafted silica capillaries, the baseline separation of steroids was successfully achieved by only changing temperature. The incorporation of hydrophobic PBMA chains in grafted PIPAAm enhanced the hydrophobic interaction with testosterone above the transition temperature. The surface modification of hydrophobicity-enhanced thermoresponsive polymers is a promising method for the preparation of thermoresponsive biointerfaces that can effectively modulated their biomolecule and cell adsorption with the wide dynamic range of hydrophilic/hydrophobic property change across the transition temperature.
KW - Atom transfer radical polymerization
KW - Block copolymer
KW - Capillary
KW - Initiator density
KW - N-Isopropylacrylamide
KW - Separation
KW - Wettability
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U2 - 10.1016/j.colsurfb.2011.10.033
DO - 10.1016/j.colsurfb.2011.10.033
M3 - Article
C2 - 22143027
AN - SCOPUS:84863857771
VL - 99
SP - 95
EP - 101
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
SN - 0927-7765
ER -