/\\/\\ Oligo melting point calculation question /\\/\\

Paul St. Amand PST at KSU.KSU.Edu
Wed Aug 2 18:30:55 EST 1995


In Maniatis the formula for calculating the Tm of an oligo is:

Tm = 81.5 + 16.6 (log10 [Na+]) + 0.41 (%G+C) - (600/length)

Why does this formula only consider Na+ ions? Wouldn't other monovalent
cations also have the same or similar effects? Should the concentration of
ALL monovalent cations (or multi-valent cations for that matter) be
included? For example, our PCRs include both Na and K salts. I guess that
the original work on this only examined Na ions (Bolton and McCarthy 1962.
PNAS 48:1390).

Paul C. St. Amand    (PST at KSU.KSU.Edu)
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