Chromatography Forum

what is the difference between column equilibrat and column condition?

Equilibrate=Flow at initial conditions
Condition=Run the gradient

In my experience, condition usually refers to something that is done only once at the beginning of a procedure or set of samples to prepare a piece of equipment like a chromatographic column for use. Equilibration usually refers to a step that is performed repeatedly in between multiple runs in a set.

I doubt that either term is rigorously defined anywhere, so usage will vary. In any given case, the interpretation should be obvious from the context.

I'd agree with the previous posters that (usually) "equilibration" is something that's done for every run, and "conditioning" is done less frequently

I’d agree with AA (i.e. equilibration is an isocratic holdup, whilst conditioning of the column is exposing the column to the changes that will occur during the planed separation/elution – typically the gradient as programmed.
I also agree with Tom that no universal definition is established – as yet. But if one uses Empower, for instance, choosing one of these two functions will cause the execution of the actions as described above.
It should also be mentioned that if the instrument method is isocratic, isotherm etc. (i.e. no timed events) choosing the function “condition columnâ€

I agree. The reason i asked is that i noticed choosing equilibrate or condition in isocratic mode didn't make any difference.

Danko and all,

Just 1 point of note (of interest?) when using Empower. Selecting "condition column" runs the gradient table but does not run the pump event table. Also, neither equilibrate or condition collect any data. If you want to run the gradient table and events tables you choose "Inject Immediate Samples", this mode collects data, runs the tables but does not do a physical injection. Very useful for diagnosing pump and mobile phase problems.

I use Waters/Empower 2 – This is how I understand it:

Condition: To create the “conditionsâ€

[quote="Diagnostic.Lab"]I use Waters/Empower 2 – This is how I understand it:

Condition: To create the “conditionsâ€