Trying to develop the HILIC-RID method for sugar analyte but getting very different results between two-run of the same sample. Tried 60 minute washing between two-run. The mobile phase is 75:25 ACN: water.
In HPLC analyses, all the solvents must be LC/MS grade. If you use reagent grade with purity less than 99.99%, then you may have impurities affecting your chromatography.
In any case, it seems that the first run did not go well regardless of the type of acetonitrile used. It seems that the washing between the two runs optimized the apparatus conditions to the following running.