Posted by
James Pawley on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Fluorophore-bleaching-by-excitation-light-sources-tp592521p592532.html
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>I don't understand this. The only explanation I can think of is that
>that the excitation wavelengths are _not_ the same in the two
>cases.(if they were and the power is the same the photon flux is the
>same). Any other comments/views?
>
>Regards.
>
>Gerard Whoriskey wrote:
>>Commercial interest.
>>
>>We have recently had preliminary feedback from a number of
>>independent sources that show much reduced bleaching when a sample
>>is excited using an LED source rather than a Hg bulb. These tests,
>>carried out with identical powers in the excitation bandpass
>>region, showed that imaging could be carried out for up to three
>>times longer.
>>On live tests cells were seen to be still living happily after
>>being exposed for twice the time it took to kill the cells under Hg
>>excitation. We are still gathering information on this and intend
>>to publish in due course.
Need to check that both systems have UV absorption filters or
optics... If you have quartz optics, and no UV filter, then you are
relying on the blocking in the barrier filter, which is not always
enough.
LEDs have no UV but Hg does.
Jim Pawley
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