column efficiency test solution

[bloodstone001]

Hi, friends!
I want to draft a SOP of column effiency test. I know some chemicals like uracil,naphthalene and fluorene are the most common materials to implement this test, but have no idea about their solution concentration and injecting volumn. So I need your help.

[Veronika R. Meyer]

For reversed-phase columns I recommend the parabens: a mixture of methylparaben, ethylparaben, propylparaben, and butylparaben in water/methanol or water/acetonitrile. The solvent for these solutes should have a lower percentage of methanol than the mobile phase has. The composition of the mobile phase needs to be adapted to the properties of the column, i.e. the parabens should be eluted within 10 minutes or so and the first peak should be retarded (k not smaller than 1). So when you have found out the best composition of the mobile phase (water/methanol or water/acetonitrile) you prepare the real test solution with less methanol or water than the mobile phase has.
The concentration and the injection volume depends on the dimensions of the column and the properties of the detector used. With a UV detector you should get peaks not larger than approx. 0.5 AU. The volume is e.g. 10 ul for a column with i.d. 4.6 mm or less for a thinner column.
This is a very general test for the quality of the column packing. There are more sophisticated tests which give information about the acidic, basic, or polar selectivity, see e.g. Claessens, Trends Anal. Chem. 20 (2001) p. 563.
Veronika

[michaelcarolus]

We perform column efficiency on all our new columns as per suppliers method. eg. Waters, Phenomenex. We compare our results to that of the supplier. (coa supplied with each column). If there is a significant difference between our result and the suppliers result the column is returned to the supplier. Request the info you need from the manufacturer.

Hope this helps.
Mike

[tom jupille]

I'll add a comment that (I think) both of the previous posts took for granted that everyone knows, and that is that any efficiency test of this type may not indicate how the column will perform in any specific method. If you know what method the column will be used with, the best test is a check sample ("system suitability sample") for your method.

If the column is intentended for "general purpose" use, then ignore the preceding statement.