Carbon-on-metal films for surface plasmon resonance detection of DNA arrays.
Surface plasmon resonance (SPR) imaging affords label-free monitoring of biomolecule interactions in an array format. A surface plasmon conducting metal thin film is required for SPR measurements. Gold thin films are traditionally used in SPR experiments as they are readily functionalized with thiol-containing molecules through formation of a gold-sulfur bond. The lability of this gold-thiol linkage upon exposure to oxidizing conditions and ultraviolet light renders these surfaces incompatible with light-directed synthetic methods for fabricating DNA arrays. It is shown here that applying a thin carbon overlayer to the gold surface yields a chemically robust substrate that permits light-directed synthesis and also supports surface plasmons. DNA arrays fabricated on these carbon-metal substrates are used to analyze two classes of biomolecular interactions: DNA-DNA and DNA-protein. This new strategy allows the combinatorial study of binding interactions directly from native, unmodified biomolecules of interest and offers the possibility of discovering new ligands in complex mixtures such as cell lysates.
Lockett
Matthew R
MR
Department of Chemistry, Center for Nanotechnology, and Genome Center of Wisconsin, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA.
Weibel
Stephen C
SC
Phillips
Margaret F
MF
Shortreed
Michael R
MR
Sun
Bin
B
Corn
Robert M
RM
Hamers
Robert J
RJ
Cerrina
Franco
F
Smith
Lloyd M
LM
D002244:Carbon / Q000737:chemistry*; D004247:DNA / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D020411:Oligonucleotide Array Sequence Analysis; D010084:Oxidation-Reduction; D011485:Protein Binding; D011506:Proteins / Q000032:analysis*; D020349:Surface Plasmon Resonance / Q000379:methods*; D014466:Ultraviolet Rays
D011506:Proteins; D002244:Carbon; D006046:Gold; D004247:DNA