Chromatography Forum

Hello
I am having some problems with my RI detector. I do not perform standard HPLC analyses with my HPLC system, but do adsorption experiments with it. For this, I pack an HPLC empty column with adsorbent powder, inject my adsorptive solutions and then want to determine isotherms based on the resulting chromatogram. I used ultrapure water as the eluent. My samples are various sugars that were dissolved in ultrapure water.
My big problem now is that two peaks overlap in my chromatogram: the sugar peak and another peak. Since the eluent and the injection solvent are identical, I strongly suspect that the second peak is caused by dissolved gases in my sample.
Normally, such problems can be solved by the column packing or column length. But I don't have too much room for manoeuvre, because pressure problems arise if the columns are too long. (As I said, these are self-packed columns, which in any case cannot be packed perfectly homogeneously).
Does anyone have an idea how else I could get around/fix/solve this peak overlay? I am very grateful for any help!

If the problem *is* dissolved air (certainly possible), try degassing your water and also make up your standards in degassed water.
Another (less likely) possibility is temperature differences. Ideally your solvent and sample should be at the same temp.