PolyAlign: A Versatile LC-MS Data Alignment Tool for Landmark-Selected and -Automated Use
Figure 5
An example of alignment of two LC-MALDI maps. (a) shows two maps before alignment. The reference map is shown in red and the target in green. The target map is going to be warped. The arrows highlight two peptide peaks in the left-hand map in different locations. The other with approx 1280 Da and retention time window of 2465–2535 (reference, red) and 2670–2730 (target, green) seconds. The other peak with approx 1500 Da and retention time window around 2720–2810 (reference, red) and 2920–3030 (target, green) seconds. All the peaks of the target map are returned to the corresponding retention time values of the reference map in (b), and the exactly overlapping peaks turn to yellow. Since the data is from serum digest of two different individuals there is, and should be, orphan peaks that only appear in one or the other sample. Notice the longer retention time window of the higher-intensity peaks.
