Zero-mode waveguides for single-molecule analysis at high concentrations.

M J Levene; J Korlach; S W Turner; M Foquet; H G Craighead; W W Webb

doi:10.1126/science.1079700

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Zero-mode waveguides for single-molecule analysis at high concentrations.

M J Levene·J Korlach·S W Turner·M Foquet·H G Craighead·W W Webb

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Abstract

Optical approaches for observing the dynamics of single molecules have required pico- to nanomolar concentrations of fluorophore in order to isolate individual molecules. However, many biologically relevant processes occur at micromolar ligand concentrations, necessitating a reduction in the conventional observation volume by three orders of magnitude. We show that arrays of zero-mode waveguides consisting of subwavelength holes in a metal film provide a simple and highly parallel means for studying single-molecule dynamics at micromolar concentrations with microsecond temporal resolution. We present observations of DNA polymerase activity as an example of the effectiveness of zero-mode waveguides for performing single-molecule experiments at high concentrations.

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Biochemistry Computer Simulation Coumarins DNA DNA-Directed DNA Polymerase Deoxycytosine Nucleotides Diffusion Enzymes, Immobilized Finite Element Analysis Fluorescence Fluorescent Dyes Ligands Light Nanotechnology Optics and Photonics Spectrometry, Fluorescence Journal Article Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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M J Levene, J Korlach, S W Turner, M Foquet, H G Craighead, W W Webb. 2003-01-31. Zero-mode waveguides for single-molecule analysis at high concentrations.. https://doi.org/10.1126/science.1079700

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