Even the simple UF clean-up procedure considerably reduced
the background noise to the levels of the chromatogram baseline
(min 20–195); it also reduced the height of most of the peaks.
Nevertheless, in most of the cases, the background noise reduction
was higher than those of the peak height, allowing the acquisition of more accurate ultraviolet and mass spectra. Alternatively, when
peak signal intensity diminished too much, membranes with 50 or
100 kDa MMCO can be used, but when the background noise
remained quite high, membranes with 3 kDa MMCO are recommended.
In this way, some peaks (mostly from the first half of the
chromatogram) were best identified in the chromatogram of the
GSE-W, whereas others were best identified in the chromatograms
of the 10 or 3 kDa MMCO permeates (GSE-UF10 or GSE-UF3)