Hello,
 
In reply to Tim Boblitt concerning the relative merits of an argon laser as
compared to a Krypton/argon laser I'd like to add the following points.
 
We are running a BioRad MRC 600 presently with a Krypton/Argon laser, but
previously we had an Argon ion laser for about 12 months while our
krypton/argon laser was being repaired.
 
The krypton/argon laser is intended for dual labelling, or in fact triple
labelling as there are 3 main lines at 488nm (blue), 568nm (yellow) and
647nm (red). The argon ion laser only has the main blue 488nm line. The
extra lines allows one to optimally excite two different fluorophores (eg
fluorescein & rhodamine) and then collect the two different emissions (red
and green). Thus one can perform very good separation of the two
fluorophores when doing dual labelling.
 
Now for the down side. The krypton/argon laser is much more difficult to
keep running properly, and even if it does run optimally the life time of
the krypton/argon is much shorter than the argon ion laser. We have had a
lot of trouble with the krypton/argon on our MRC600 but BioRad now claims
that problems with the krypton/argon laser have been ironed out - we'll wait
and see on that one!
 
If you are doing double/triple labelling then the krypton/argon laser is the
way to go, but expect to have some hassles!
 
Hope this is of some help,
 
Bye, Alan Hibbs
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Dr. Alan R. Hibbs                              FAX: 07 362 0104
Queensland Institute of Medical Research     Phone: 07 362 0416
PO Royal Brisbane Hospital                   email: [log in to unmask]
Herston, Brisbane, Qld., 4029
AUSTRALIA
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