Protein interactions with model chromatographic stationary phases constructed using self-assembled monolayers.
Model surfaces representative of chromatographic stationary phases were developed by immobilising an homologous series (C2-C18) of n-alkylthiols, mixed monolayers of C4/C18 and thioalkanes with alcohol, carboxylic acid, amino and sulphonic acid terminal groups onto a flat, silver-coated glass surface using self-assembled monolayer (SAM) chemistry. The processes of adsorption and desorption of serum albumins onto the monolayer surfaces was monitored in real-time using surface plasmon resonance (SPR). Alkyl-terminated SAMs all showed a strong adsorption of bovine serum albumin which was largely independent of alkyl chain length, the ratio of mixed C4/C18 SAMs or the solution pH/ionic strength. The adsorption of human serum albumin to carboxylic and amine terminated SAMs was shown to be predominantly via non-electrostatic interactions (hydrophobic or hydrogen bonding). However, sulphonic acid terminated SAMs showed almost exclusively electrostatic interactions with human serum albumin. This preliminary work using self-assembled monolayer chemistry confirms the usefulness of well characterised SAMs surfaces for investigating protein adsorption and desorption onto/from model chromatography surfaces and gives some guidance for selecting appropriate functionalities to develop better surfaces for chromatography and electrophoresis.
Barrett
David A
DA
School of Pharmacy, University of Nottingham, University Park, Nottingham NG7 2RD, UK. david.barrett@nottingham.ac.uk
Power
Gillian M
GM
Hussain
Maruf A
MA
Pitfield
Ian D
ID
Shaw
P Nicholas
PN
Davies
Martyn C
MC
D000478:Alkylation; D000818:Animals; D002417:Cattle; D002845:Chromatography / Q000295:instrumentation*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D009994:Osmolar Concentration; D011485:Protein Binding; D012709:Serum Albumin / Q000737:chemistry* / Q000378:metabolism*; D013438:Sulfhydryl Compounds / Q000737:chemistry / Q000378:metabolism; D020349:Surface Plasmon Resonance
D012709:Serum Albumin; D013438:Sulfhydryl Compounds