COLL 457 |
| Yukio Nagasaki1, Katsumi Uchida1, Miki Kato1, Tadahito Takahashi1, Hidenori Otsuka2, and Kazunori Kataoka3. (1) Department of Materials Science, Tokyo University of Science, Yamazaki 2641, Noda, 278-8510, Japan, (2) Artificial Organ Materials Research Group, Biomaterials Center, National Institute for Materials Science, 1-1 Namiki, Tsukuba, 305-0044, Japan, (3) Department of Materials Science, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan |
| PEG tethered chains surface was constructed on the gold surface using heterobifunctional poly(ethylene glycol), heteroPEG, which possessed an acetal group at one end and a mercapto group at the other end (alpha-acetal-omega-mercapto-PEG). The density of PEG tethered chains on the surface substantially increased with repetitive conjugation/rinsing cycle of PEG on the sensor chip, allowing to dramatically reduce the nonspecific protein adsorption on the sensor surface. Notably, the successive PEGylation with longer, and then shorter PEG, e.g. treatment with shorter PEG (2kDa) of the preconstructed longer PEG (5kDa) tethered chains surface, resulted in almost complete prevention of nonspecific protein adsorption. The acetal group at the distal end of the tethered PEG was converted to aldehyde group by the acid treatment, followed by the installation of biocytin hydrazide thorough Schiff base formation. SPR sensing of streptavidin was done with very high S/N ratio even in the protein medium by using biotinylated-PEG (5kDa) immobilized chip with filler layer of short 2kDa PEG. |
|
“Smart” Polymers on Surfaces and Colloids
2:00 PM-4:40 PM, Wednesday, March 31, 2004 Marriott -- Grand Ballroom J, Oral
Division of Colloid and Surface Chemistry |