Re: Fluorophore bleaching by excitation light sources

Posted by Knecht, David on
URL: http://confocal-microscopy-list.275.s1.nabble.com/Fluorophore-bleaching-by-excitation-light-sources-tp592521p592524.html

Search the CONFOCAL archive at http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal I have used the CoolLED system, and it is not operating in strobe mode.  It is continuous illumination.  The UV question is interesting.  Is there an easy way to test if there is UV leaking through the epi filter set with the mercury burner?  Dave

On Mar 12, 2008, at 4:27 PM, Stanislav Vitha wrote:

Search the CONFOCAL archive at
http://listserv.acsu.buffalo.edu/cgi-bin/wa?S1=confocal

Regarding the difference between LED illumination and Hg lamp -
Perhaps if the illumination is not continuous but is set up for strobe
operation of the LED, this could allow dark state relaxation an prolong
the life of the fluorophore (I am not sure the same would apply to the
life of the cell). - The time between light pulses should be more than one
microscecond.
reference:   
Gerald Donnert, Christian Eggeling & Stefan W Hell: Major signal increase
in fluorescence microscopy through dark-state relaxation. Nature Methods -
4, 81 - 86 (2007)


Stan Vitha

Dr. David Knecht    

Department of Molecular and Cell Biology

Co-head Flow Cytometry and Confocal Microscopy Facility

U-3125

91 N. Eagleville Rd.

University of Connecticut

Storrs, CT 06269

860-486-2200

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