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Single molecule fluorescence

  1. Jun 9, 2010 #1

    I'm doing some calculations on fluorescence and I'm a little stuck on statistics.
    Let's say I need to measure 20 seconds to collect 10000 photons from a single molecule.
    Then I can say well I want to measure at most 1 second and therefore I need 20 molecules in order to collect 10000 photons in that second.

    Is this way of thinking reasonable? Or do I need to take into account some statistics with S/N ratio and say: Poisson distribution.

    I can't find any sources to found this reasoning.

    Thanks in advance,
  2. jcsd
  3. Jun 9, 2010 #2

    Andy Resnick

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  4. Jun 9, 2010 #3
    Ok. Let me make myself more clear.
    I know it's about high resolution that's the reason I use these.
    The problem is, the molecule can only emit for about 1 second and then it is destroyed.
    So I take more molecules, which results indeed in less spatial resolution, to collect the needed amount of photons in the range of the 'lifetime' of the molecules (1second).
    But what I was wondering, can I divide the time (t) it takes for 1 molecule to emit 'theoretically' the amount of photons by x molecules and say these molecules will emit the same amount of photons in t/x seconds.
    Or do I need to take some statistics into account before I can simply state this?
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