Membrane-protein binding measured with solution-phase plasmonic nanocube sensors

1] Howard Hughes Medical Institute, University of California, Berkeley, California, USA. [2] Department of Chemistry, University of California, Berkeley, California, USA. [3] Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA.
Nature Methods (Impact Factor: 32.07). 10/2012; 9(12). DOI: 10.1038/nmeth.2211
Source: PubMed


We describe a solution-phase sensor of lipid-protein binding based on localized surface plasmon resonance (LSPR) of silver nanocubes. When silica-coated nanocubes are mixed in a suspension of lipid vesicles, supported membranes spontaneously assemble on their surfaces. Using a standard laboratory spectrophotometer, we calibrated the LSPR peak shift due to protein binding to the membrane surface and then characterized the lipid-binding specificity of a pleckstrin homology domain protein.

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