Negative peaks in my dialysates interfere with my analysis
Negative peaks appear in the chromatograms of brain dialysates. They overlap with relevant analyte peaks.
Dialysates usually contain relatively high concentrations of ions such as potassium, sodium, chloride, magnesium. These ions may appear as negative peaks in a chromatogram.
Adding a chelating agent such as EDTA affects the chromatographic behavior of some of these ions. Alternatively, the ion pair (OSA) concentration or pH can be changed to get rid of shouldering or overlapping peaks.