TY - JOUR
T1 - Photoinduced phospholipid polymer grafting on Parylene film
T2 - Advanced lubrication and antibiofouling properties
AU - Goda, Tatsuro
AU - Konno, Tomohiro
AU - Takai, Madoka
AU - Ishihara, Kazuhiko
N1 - Funding Information:
We express our gratitude to Dr. S. Takeuchi and Dr. H. Suzuki at the University of Tokyo for their help with the Parylene C coatings. We are indebted to Dr. T. Hanawa and Dr. Y. Iwasaki at the Tokyo Medical and Dental University for the ellipsometry support. One of the authors (T.G) wishes to express thanks for the support from a Grant for 21st Century COE Program for “Human-Friendly Materials based on Chemistry,” MEXT, Japan.
PY - 2007/1/15
Y1 - 2007/1/15
N2 - Poly(p-xylylene) (Parylene C) coatings have been applied in implantable electronic devices because of their electrical insulation and moisture barrier properties. To provide lubrication and an antibiofouling surface, a biomimetic phospholipid polymer - poly(2-methacryloyloxyethyl phosphorylcholine (MPC)) - was grafted from the surface using UV irradiation with benzophenone as an initiator. The poly(MPC) grafting on the Parylene C films was confirmed by attenuated total reflection-Fourier transfer inflated irradiation, X-ray photoelectron spectroscopy and ellipsometry. These analyses indicated that the Parylene C films were completely covered by the poly(MPC)-graft layer with an average thickness of 140 nm under dry condition. The atomic force microscope (AFM) images revealed that the poly(MPC)-graft chains extended under wet condition. However, they formed globular structures under dry condition. Water contact angle measurements revealed a decreased receding angle of 29.5° on the poly(MPC)-grafted surface with a high hysteresis of 41.4°. These results indicate that the poly(MPC)-graft chains gain mobility in a wet environment. The average kinetic friction coefficient of the poly(MPC)-grafted surface in water was 0.018, which was 90% lower than that of the original surface. The in vitro single protein adsorption reduced by over 70% due to the poly(MPC) grafting. The hydrated poly(MPC)-graft chains are considered to provide lubrication and antibiofouling properties. The surface zeta potential measurement clarified the electroneutrality of the poly(MPC)-grafted surface. We concluded that the poly(MPC) grafting from the Parylene C layer significantly improved its surface properties and, subsequently, its biological properties.
AB - Poly(p-xylylene) (Parylene C) coatings have been applied in implantable electronic devices because of their electrical insulation and moisture barrier properties. To provide lubrication and an antibiofouling surface, a biomimetic phospholipid polymer - poly(2-methacryloyloxyethyl phosphorylcholine (MPC)) - was grafted from the surface using UV irradiation with benzophenone as an initiator. The poly(MPC) grafting on the Parylene C films was confirmed by attenuated total reflection-Fourier transfer inflated irradiation, X-ray photoelectron spectroscopy and ellipsometry. These analyses indicated that the Parylene C films were completely covered by the poly(MPC)-graft layer with an average thickness of 140 nm under dry condition. The atomic force microscope (AFM) images revealed that the poly(MPC)-graft chains extended under wet condition. However, they formed globular structures under dry condition. Water contact angle measurements revealed a decreased receding angle of 29.5° on the poly(MPC)-grafted surface with a high hysteresis of 41.4°. These results indicate that the poly(MPC)-graft chains gain mobility in a wet environment. The average kinetic friction coefficient of the poly(MPC)-grafted surface in water was 0.018, which was 90% lower than that of the original surface. The in vitro single protein adsorption reduced by over 70% due to the poly(MPC) grafting. The hydrated poly(MPC)-graft chains are considered to provide lubrication and antibiofouling properties. The surface zeta potential measurement clarified the electroneutrality of the poly(MPC)-grafted surface. We concluded that the poly(MPC) grafting from the Parylene C layer significantly improved its surface properties and, subsequently, its biological properties.
KW - Lubrication
KW - Parylene
KW - Phosphorylcholine
KW - Photografting
KW - Protein adsorption
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U2 - 10.1016/j.colsurfb.2006.09.006
DO - 10.1016/j.colsurfb.2006.09.006
M3 - Article
C2 - 17137760
AN - SCOPUS:33845727524
SN - 0927-7765
VL - 54
SP - 67
EP - 73
JO - Colloids and Surfaces B: Biointerfaces
JF - Colloids and Surfaces B: Biointerfaces
IS - 1
ER -