title: Control over binding stoichiometry and specificity in the supramolecular immobilization of cytochrome c on a molecular printboard.
abstract: Here, the stepwise assembly of an electroactive bionanostructure on a molecular printboard is described. The system consists of a cyclodextrin receptor monolayer (molecular printboard) on glass, a divalent linker, streptavidin (SAv), and biotinylated cytochrome c (cyt c). The divalent linker consists of a biotin moiety for binding to SAv and two adamantyl moieties for supramolecular host-guest interaction at the cyclodextrin molecular printboard. The binding of biotinylated cyt c onto a SAv layer bound to preadsorbed linker appeared to be highly specific. The coverages of cyt c as assessed by UV-vis spectroscopy and scanning electrochemical microscopy (SECM) appeared to be identical indicating that all cyt c units remained active. Moreover, the coverage values corresponded well with an estimate based on steric requirements, and the binding stoichiometry was therefore found to be by two biotin moieties of cyt c per one SAv molecule.
authors.affiliation: Molecular Nanofabrication group, MESA+ Institute for Nanotechnology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
authors.forename: Manon J W
authors.initials: MJ
authors.lastname: Ludden
authors.forename: Jatin K
authors.initials: JK
authors.lastname: Sinha
authors.forename: Gunther
authors.initials: G
authors.lastname: Wittstock
authors.forename: David N
authors.initials: DN
authors.lastname: Reinhoudt
authors.forename: Jurriaan
authors.initials: J
authors.lastname: Huskens
mesh_terms: D000327:Adsorption; D001665:Binding Sites; D001710:Biotin / Q000737:chemistry; D045304:Cytochromes c / Q000737:chemistry*; D004563:Electrochemistry; D004800:Enzymes, Immobilized / Q000737:chemistry*; D005898:Glass / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D046911:Macromolecular Substances / Q000737:chemistry; D008855:Microscopy, Electron, Scanning / Q000379:methods; D008958:Models, Molecular; D015394:Molecular Structure; D013056:Spectrophotometry, Ultraviolet / Q000379:methods; D019809:Streptavidin / Q000737:chemistry*; D013499:Surface Properties; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D004800:Enzymes, Immobilized; D046911:Macromolecular Substances; D047392:beta-Cyclodextrins; D001710:Biotin; D006046:Gold; D045304:Cytochromes c; D019809:Streptavidin