\PROTOCOLS\HIS100.SAM

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MAKING 100 mM HISTIDINOL FOR

SELECTION OF MAMMALIAN CELL CULTURES

A. Make 100 mM Hepes in T.C. grade water, pH to 7.4 with NaOH.

B. Add L-Histidinol to Hepes (Sigma #H 6647) to 100 mM.

C. Readjust pH to 7.4 with NaOH.

D. Filter sterilize using 0.2 m vacuum unit.

E. Refrigerate the solution if it is to be used soon, or freeze aliquots for long-term (>2 week) storage.

F. Final concentration for selection 7-10 mM; for carrying cells post selection 5 mM.