The STREAM (suppressor treatment reusing eluent after measurement) is applied since quite some time. The suppressor rinsing with suppressed eluent is advantageous over ultrapure water rinsing: a smaller water dip, faster MSM equilibration, and the avoidance of an additional water supply are just a few. Injecting samples containing iron in the matrix under sulfuric acid regeneration yields reduced peak areas and broader peaks for phosphate. Switching to a regenerant based on sulfuric and oxalic acid allows full regeneration of the MSM. The overlay above shows three subsequently taken chromatograms after more than 300 injections of 10 mg/L iron(II) onto one single MSM chamber. No difference in peak shape or peak area is observed.
