Facile and rapid direct gold surface immobilization with controlled orientation for carbohydrates.
Effective surface immobilization is a prerequisite for numerous carbohydrate-related studies including carbohydrate-biomolecule interactions. In the present work, we report a simple and rapid modification technique for diverse carbohydrate types in which direct oriented immobilization onto a gold surface is accomplished by coupling the amine group of a thiol group-bearing aminophenyl disulfide as a new coupling reagent with an aldehyde group of the terminal reducing sugar in the carbohydrate. To demonstrate the generality of this proposed reductive amination method, we examined its use for three types of carbohydrates: glucose (monosaccharide), lactose (disaccharide), and GM1 pentasaccharide. Through successful mass identifications of the modified carbohydrates, direct binding assays on gold surface using surface plasmon resonance and electrochemical methods, and a terminal galactose-binding lectin assay using atomic force microscopy, we confirmed several advantages including direct and rapid one-step immobilization onto a gold surface and exposure of functional carbohydrate moieties through oriented modification of the terminal reducing sugar. Therefore, this facile modification and immobilization method can be successfully used for diverse biomimetic studies of carbohydrates, including carbohydrate-biomolecule interactions and carbohydrate sensor or array development for diagnosis and screening.
Seo
Jeong Hyun
JH
Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, Korea.
Adachi
Kyouichi
K
Lee
Bong Kuk
BK
Kang
Dong Gyun
DG
Kim
Yeon Kyu
YK
Kim
Kyoung Ro
KR
Lee
Hea Yeon
HY
Kawai
Tomoji
T
Cha
Hyung Joon
HJ
D002241:Carbohydrates / Q000737:chemistry*; D005663:Furans / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D020349:Surface Plasmon Resonance; D013499:Surface Properties; D013997:Time Factors
D002241:Carbohydrates; D005663:Furans; D006046:Gold