HPLC retention time question

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Hi,

I'm wondering if there is an equation that ties in dimensions of a reverse phased column being, 15cm x 0.46 cm , retention time of Uracil being 1.5 minutes and the flow rate being 1.0mL/min? If there even is an equation.

I basically need a tm value for uracil for the equation:

K=(tr-tm)/tm

Unless i'm barking up the wrong tree, but I believe this is the way to carry on with the question to calculate the retention time from a concentration point on a graph. The lack of tm is the only thing stopping me from carrying on.

Any guidance would be great! :)
That's easy. In (most) reversed-phase systems, uracil is unretained and is therefore used as a marker for tm. So in your equation, tr = tm and therefore, K = 0

Note that LC terminology is not hugely consistent. tm is often symbolized as t0. Your K is often symbolized as k'
-- Tom Jupille
LC Resources / Separation Science Associates
tjupille@lcresources.com
+ 1 (925) 297-5374
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