Surface functionalization chemistries on highly sensitive silica-based sensor chips.
The surfaces of silica-based sensor chips, designed for evanescent-field-coupled waveguide-mode sensors, were functionalized using various surface chemistries. The immobilization of molecular entities on the functionalized silica surfaces was monitored using various microscopic techniques (scanning electron, fluorescence, and atomic force microscopies). Further, gold nanoparticle-based signal enhancement analyses were performed with protein conjugation on different functionalized surfaces using a waveguide-mode sensor. Based on these analyses, the sensor surfaces modified with glutaraldehyde (Glu) and carbonyldiimidazole were found to be good for molecules of different sizes. In addition, it can be inferred that the Glu-modified surface may be suitable for small molecules with diameters around 5 nm owing to its surface roughness. The modified surface with carbonyldiimidazole is suitable for the direct immobilization of larger molecules especially for biomolecular assemblies without intermediate chemical modifications.
Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Central 5, 1-1-1 Higashi, Tsukuba, Ibaraki 305-8565, Japan. gopi-subashchandrabose@aist.go.jp
Subash C B
SC
Gopinath
Koichi
K
Awazu
Makoto
M
Fujimaki
Kazufumi
K
Shimizu
Wataru
W
Mizutani
Kiyomi
K
Tsukagoshi
D005976:Glutaral / Q000737:chemistry*; D007093:Imidazoles / Q000737:chemistry*; D008856:Microscopy, Fluorescence; D010316:Particle Size; D040081:Protein Array Analysis / Q000295:instrumentation / Q000379:methods*; D012822:Silicon Dioxide / Q000737:chemistry*; D019809:Streptavidin / Q000032:analysis*; D013499:Surface Properties
D007093:Imidazoles; C006900:N,N-carbonyldiimidazole; D012822:Silicon Dioxide; D019809:Streptavidin; D005976:Glutaral