title: Immobilization of carbohydrate clusters on a quartz crystal microbalance sensor surface.
abstract: The immobilization of carbohydrates on gold surfaces is a prerequisite technology for carbohydrate-related studies, including those of carbohydrate-biomolecule interactions. Glycolipid domains in cell membranes, such as lipid rafts, are thought to play an important role in cell biology through their carbohydrate portions. To understand the recognition of glycolipid domains such as receptors for bacterial toxins and viruses, we immobilized clusters of carbohydrates on a gold surface by using polyamidoamine (PAMAM) dendrimers as a scaffold. The PAMAM dendrimers were adsorbed on the gold-coated surface of a quartz crystal microbalance (QCM) sensor and were observed by means of QCM with dissipation (QCM-D). After adsorption of the PAMAM dendrimers, lysoganglioside-GM(1) and 12-aminododecyl-N-acetylglucosaminide (GlcNAc-C12-NH(2)) were immobilized on the amino groups of PAMAM dendrimers by means of an NH(2) cross-linker. Immobilization of the carbohydrates was confirmed by observation of their specific interaction with anti-ganglioside GM(1) antibody or wheat germ agglutinin (WGA). Surfaces with different GlcNAc-C12-NH(2) cluster sizes and densities were prepared by varying the size of the PAMAM dendrimers or the concentration of GlcNAc-C12-NH(2) immobilized on the dendrimers, respectively. Analysis of the binding between the GlcNAc-C12-NH(2)-immobilized surface and WGA revealed that the size of the PAMAM dendrimers influenced the GlcNAc-C12-NH(2)-WGA interaction, with larger dendrimers resulting in higher WGA binding constants.
authors.affiliation: Japan Chemical Innovation Institute, 1-3-5 Jimbocho, Chiyoda-ku, Tokyo 101-0051, Japan.
authors.forename: Masayo
authors.initials: M
authors.lastname: Ogiso
authors.forename: Koji
authors.initials: K
authors.lastname: Matsuoka
authors.forename: Tomoko
authors.initials: T
authors.lastname: Okada
authors.forename: Tomoko
authors.initials: T
authors.lastname: Imai
authors.forename: Miki
authors.initials: M
authors.lastname: Itoh
authors.forename: Takeshi
authors.initials: T
authors.lastname: Imamura
authors.forename: Yoshimi
authors.initials: Y
authors.lastname: Haga
authors.forename: Kenichi
authors.initials: K
authors.lastname: Hatanaka
authors.forename: Norihiko
authors.initials: N
authors.lastname: Minoura
mesh_terms: D000327:Adsorption; D002241:Carbohydrates / Q000737:chemistry*; D050091:Dendrimers / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D015394:Molecular Structure; D011073:Polyamines / Q000737:chemistry; D058525:Quartz Crystal Microbalance Techniques; D013499:Surface Properties
chemical_list: D002241:Carbohydrates; D050091:Dendrimers; C531249:Poly(amidoamine); D011073:Polyamines; D006046:Gold