TY - JOUR
T1 - Aldehyde-mediated protein-to-surface tethering via controlled diazonium electrode functionalization using protected hydroxylamines
AU - Yates, Nick
AU - Dowsett, Mark
AU - Bentley, Phillip
AU - Dickenson-Fogg, Jack
AU - Pratt, Andrew
AU - Blanford, Christopher
AU - Fascione, Martin Anthony
AU - Parkin, Alison
N1 - © 2019 American Chemical Society. This is an author-produced version of the published paper. Uploaded in accordance with the publisher’s self-archiving policy. Further copying may not be permitted; contact the publisher for details.
PY - 2019/11/13
Y1 - 2019/11/13
N2 - 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 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. Bio-conjugation is demonstrated via the coupling of a dilute (50 µM) solution of periodate-oxidized horseradish peroxidase enzyme to a functionalized gold surface under bio-compatible conditions (H2O solvent, pH 4.5, 25 °C).
AB - 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 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. Bio-conjugation is demonstrated via the coupling of a dilute (50 µM) solution of periodate-oxidized horseradish peroxidase enzyme to a functionalized gold surface under bio-compatible conditions (H2O solvent, pH 4.5, 25 °C).
U2 - 10.1021/acs.langmuir.9b01254
DO - 10.1021/acs.langmuir.9b01254
M3 - Article
SN - 0743-7463
JO - Langmuir
JF - Langmuir
ER -