USP columns

[Besma2]

HI everyone
my question concerns HPLC Columns propose in USP, is there a difference between aordinnaire (L1) C18 column and columns ( L1 endcapped , base deactivated )
thank you

[HPLCaddict]

Yes and no, there might be a difference. The designation "L1" applies to the whole plethora of C18 columns available. But not every of these columns is base-deactivated and endcapped. So "L1 endcapped, base deactivated" is only a subset of that vast array.
In other words, every "L1, endcapped, base-deactivated" column is also an ordinnaire "L1"-column, but not every "L1"-column is also endcapped and base-deactivated.

[Gerhard Kratz]

Excellent explanation HPLCaddict.

[Besma2]

thank you for your explanation