Chromatography Forum

Dear Friends,

I would like to hear from anyone that has experience working separations at low pH (2-3) on Polaris A columns. No clear information is provided by the manufacturer as to the nature of the polar embedded phase, or its stability to buffers and low pH conditions.

I have had some bad experiences with similar columns containing "epoxide" phases, and before exposing the Polaris A columns to "harsh" conditions I would like to know more about their stability.

Please remember that ther are two types of Polaris columns, Polaris A and Polaris-ether. I am interested on the A type.

Thanks,

josebenjamin

josebenjamin

Polaris-A columns use an amide linker before the C18. It should be as robust as any other C18 column. According the the literature it is stable don to pH 1.5. I use one with ammonium acetate buffer and routinely get 700-1000 injections of reasonably "dirty" samples. I discard columns when I start to get peak splitting most likely due to accumulation of protein at the head of the column.