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Caffeine, MRFA, and Ultramark 1621 Stock Solutions
140
LTQ XL Getting Started
Thermo Electron Corporation
Caffeine, MRFA, and
Ultramark 1621 Stock
Solutions
For tuning and calibrating the ESI system, you use a solution of caffeine,
MRFA, and Ultramark 1621 in an acetonitrile:methanol:water solution
containing 1% acetic acid. You prepare the calibration solution from each of
the following:
• Caffeine stock solution
• MRFA stock solution
• Ultramark 1621 stock solution
Note
Vials of caffeine, MRFA, and Ultramark 1621 are included in the
API accessory kit. These compounds are available from Sigma Chemical
Co. The Sigma caffeine Product Number is C6035 (Caffeine Solution,
drug standard 1mg/mL
±
5% in methanol). The Sigma MRFA Product
Number is M1170 (MRFA=Met-Arg-Phe-Ala acetate salt). To order
more of these compounds from Sigma, write or call:
Sigma Chemical Company
P. O. Box 14508
St. Louis, Missouri, USA 63178-9916
(800) 325-3010 (in the USA)
(905) 829-9500 (in Canada)
(314) 771-3750 (outside the USA or Canada)
www.sigmaaldrich.com