I haven't checked specifically for tyrosine, but Molecular Probes
(http://www.probes.com/) has about everything under the sun in terms of
fluorescent reagents.
Jack
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Jack Simpson, Ph.D.
Pharmakinetics Laboratories
302 West Fayette Street
Baltimore, MD 21201
410-385-4500, ext. 688
jsimpson@pharmakinetics.com
http://sx102a.niddk.nih.gov/mass/lnt/simpson.html
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