Single molecule studies, nanoaperture-enhanced fluorescence

Moreover, the studies on nanoaperture-enhanced fluorescence point out that for a properly tailored aperture, count rates per molecule greater than a few hundred thousands photons per second were readily obtained, whereas for a single molecule in open solution, fluorescence saturation prevents the count rate from exceeding a few tens of kilocounts per second. This allows for fast and reliable screening for single molecules. 

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