Membrane-protein binding measured with solution-phase plasmonic nanocube sensors
1] Howard Hughes Medical Institute, University of California, Berkeley, California, USA.  Department of Chemistry, University of California, Berkeley, California, USA.  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
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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Available from: Andrea Armani
- "In waveguide interferometer sensors, where the detection signal is typically a change in optical power, an increase in power results in an improved signal-to-noise ratio . In surface plasmon or resonant cavity based sensors, an increase in power corresponds to a narrower resonance linewidth, improving the resolution of the measurement . Therefore, it is critical that the surface functionalization does not decrease the optical power confined within the device. "
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