ORIGINAL: EurekAlert
Berkeley Lab researchers embed artificial membranes with billions of nanoantennas for enhanced optical studies
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| Gold triangle nanoparticles paired tip-to-tip in a bow-tie formation, serve as optical antennas. When a protein (green) bound to a fluorescently labeled SOS-catalyst passes through the the gaps between opposing tips of the triangles (plasmonic hot spots) fluorescence is amplified. Credit: (Image by Groves, et. al., Berkeley Lab) Usage Restrictions: courtesy of Jay Groves, Berkeley Lab, UC Berkeley, HHMI |
At the heart of the immune system that protects our bodies from disease and foreign invaders is a vast and complex communications network involving millions of cells, sending and receiving chemical signals that can mean life or death. At the heart of this vast cellular signaling network are interactions between billions of proteins and other biomolecules. These interactions, in turn, are greatly influenced by the spatial patterning of signaling and receptor molecules. The ability to observe signaling spatial patterns in the immune and other cellular systems as they evolve, and to study the impact on molecular interactions and, ultimately, cellular communication, would be a critical tool in the fight against immunological and other disorders that lead to a broad range of health problems including cancer. Such a tool is now at hand.
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| An array of gold nanoparticles in the shape of triangles that are paired in a tip-to-tip formation, like a bow-tie, can serve as optical antennas, capturing and concentrating light waves into well-defined hot spots, where the plasmonic effect is greatly amplified. Credit: (Image by Groves, et. al., Berkeley Lab). Usage Restrictions: courtesy of Jay Groves, Berkeley Lab, UC Berkeley, HHMI. |
Researchers with the U.S. Department of Energy (DOE)'s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley, have developed the first practical application of optical nanoantennas in cell membrane biology. A scientific team led by chemist Jay Groves has developed a technique for lacing artificial lipid membranes with billions of gold "bowtie" nanoantennas. Through the phenomenon known as "plasmonics," these nanoantennas can boost the intensity of a fluorescent or Raman optical signal from a protein passing through a plasmonic "hot-spot" tens of thousands of times without the protein ever being touched.
"Our technique is minimally invasive since enhancement of optical signals is achieved without requiring the molecules to directly interact with the nanoantenna," Groves says. "This is an important improvement over methods that rely on adsorption of molecules directly onto antennas where their structure, orientation, and behavior can all be altered."
Groves holds joint appointments with Berkeley Lab's Physical Biosciences Division and UC Berkeley's Chemistry Department, and is also a Howard Hughes Medical Institute investigator. He is the corresponding author of a paper that reports these results in the journal NanoLetters. The paper is titled "Single Molecule Tracking on Supported Membranes with Arrays of Optical Nanoantennas." Co-authoring the paper were Theo Lohmuller, Lars Iversen, Mark Schmidt, Christopher Rhodes, Hsiung-Lin Tu and Wan-Chen Lin.
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| Jay Groves is a chemist who holds appointments with Berkeley Lab, UC Berkeley and HHMI. Credit: (Photo by Roy Kaltschmidt, Berkeley Lab). |
