Conversion factor

[mk12]

I have free base as standard and hydrochloride salt as my sample...How I should calculate my % recovery..what will be the conversion factors..how to calculate that..thanks in advance

[JGK]

factor =MW of salt/Mw of free base, this will produce a factor >1

Multiply your results by this factor to obtain the salt concentration from the measured free base concentration.

or (preferably)

Convert you STD concs to equivalent salt concs (factor =MW of free base/Mw of salt, this will produce a factor <1), by multiplying the free base conc by the factor.

Tip: if you do the adjustment at the Stock STD prep, you only need to do one calculation (calculate all other STD concs as normal from the "adjusted" Stock STD conc)