| Autor: |
Yates ND; Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom., Dowsett MR; Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom., Bentley P; Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom., Dickenson-Fogg JA; Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom., Pratt A; Department of Physics, University of York, Heslington, York, YO10 5DD, United Kingdom., Blanford CF; School of Materials, University of Manchester, Oxford Road, Manchester, M13 9PL, United Kingdom.; Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester, M1 7DN, United Kingdom., Fascione MA; Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom., Parkin A; Department of Chemistry, University of York, Heslington, York, YO10 5DD, United Kingdom. |
| Abstrakt: |
We report a diazonium electro-grafting method for the covalent modification of conducting surfaces with aldehyde-reactive hydroxylamine functionalities that facilitate the wiring of redox-active (bio)molecules to electrode surfaces. Hydroxylamine near-monolayer formation is achieved via a phthalimide-protection and hydrazine-deprotection strategy that overcomes the multilayer formation that typically complicates diazonium surface modification. This surface modification strategy is characterized using electrochemistry (electrochemical impedance spectroscopy and cyclic voltammetry), X-ray photoelectron spectroscopy, and quartz crystal microbalance with dissipation monitoring. Thus-modified glassy carbon, boron-doped diamond, and gold surfaces are all shown to ligate to small molecule aldehydes, yielding surface coverages of 150-170, 40, and 100 pmol cm -2 , respectively. Bioconjugation is demonstrated via the coupling of a dilute (50 μM) solution of periodate-oxidized horseradish peroxidase enzyme to a functionalized gold surface under biocompatible conditions (H 2 O solvent, pH 4.5, 25 °C). |
