TY - JOUR
T1 - Sum-frequency generation analyses of the structure of water at amphoteric SAM-liquid water interfaces
AU - Nomura, Kouji
AU - Nakaji-Hirabayashi, Tadashi
AU - Gemmei-Ide, Makoto
AU - Kitano, Hiromi
AU - Noguchi, Hidenori
AU - Uosaki, Kohei
N1 - Funding Information:
This research was supported by a Grant-in-Aid for Scientific Research ( 22350101 and 26288100 ) from the Japan Society for the Promotion of Science (JSPS) and a Grant-in-Aid ( 20106007 ) from the Ministry of Education, Culture, Sports, Science and Technology (MEXT) , Tokyo, Japan. K.N. is grateful for the internship program of the NIMS.
PY - 2014/9/1
Y1 - 2014/9/1
N2 - Surfaces of both a cover glass and the flat plane of a semi-cylindrical quartz prism were modified with a mixture of positively and negatively charged silane coupling reagents (3-aminopropyltriethoxysilane (APTES) and 3-(trihydroxysilyl)propylmethylphosphonate (THPMP), respectively). The glass surface modified with a self-assembled monolayer (SAM) prepared at a mixing ratio of APTES:THPMP=4:6 was electrically almost neutral and was resistant to non-specific adsorption of proteins, whereas fibroblasts gradually adhered to an amphoteric (mixed) SAM surface probably due to its stiffness, though the number of adhered cells was relatively small. Sum frequency generation (SFG) spectra indicated that total intensity of the OH stretching region (3000-3600cm-1) for the amphoteric SAM-modified quartz immersed in liquid water was smaller than those for the positively and negatively charged SAM-modified quartz prisms and a bare quartz prism in contact with liquid water. These results suggested that water molecules at the interface of water and an amphoteric SAM-modified quartz prism are not strongly oriented in comparison with those at the interface of a lopsidedly charged SAM-modified quartz prism and bare quartz. The importance of charge neutralization for the anti-biofouling properties of solid materials was strongly suggested.
AB - Surfaces of both a cover glass and the flat plane of a semi-cylindrical quartz prism were modified with a mixture of positively and negatively charged silane coupling reagents (3-aminopropyltriethoxysilane (APTES) and 3-(trihydroxysilyl)propylmethylphosphonate (THPMP), respectively). The glass surface modified with a self-assembled monolayer (SAM) prepared at a mixing ratio of APTES:THPMP=4:6 was electrically almost neutral and was resistant to non-specific adsorption of proteins, whereas fibroblasts gradually adhered to an amphoteric (mixed) SAM surface probably due to its stiffness, though the number of adhered cells was relatively small. Sum frequency generation (SFG) spectra indicated that total intensity of the OH stretching region (3000-3600cm-1) for the amphoteric SAM-modified quartz immersed in liquid water was smaller than those for the positively and negatively charged SAM-modified quartz prisms and a bare quartz prism in contact with liquid water. These results suggested that water molecules at the interface of water and an amphoteric SAM-modified quartz prism are not strongly oriented in comparison with those at the interface of a lopsidedly charged SAM-modified quartz prism and bare quartz. The importance of charge neutralization for the anti-biofouling properties of solid materials was strongly suggested.
KW - Amphoteric SAM
KW - Biocompatibility
KW - Orientation of water molecules
KW - Silane coupling reaction
KW - Sum frequency generation
UR - http://www.scopus.com/inward/record.url?scp=84905961511&partnerID=8YFLogxK
U2 - 10.1016/j.colsurfb.2014.04.025
DO - 10.1016/j.colsurfb.2014.04.025
M3 - 学術論文
C2 - 25001187
AN - SCOPUS:84905961511
SN - 0927-7765
VL - 121
SP - 264
EP - 269
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
ER -