Fig. 4.
Amlodipine (AML) related clusters. The molecular networking and subsequent node validation process resulted in the AML-related clusters in (a). The structures for those metabolites that could be annotated by matching product ions to literature data are shown (solid boxes) and the annotation of a AML metabolite based on spectral homology and mass differences is also presented (dashed box), where mtb is short for metabolite, Glc for glucuronide, and Ox for oxidized. In total, 7 urine extracts contained one or more AML metabolites, here represented in five clusters based on the presence/absence of AML metabolites. Spectral occurrences were obtained from the molecular network, b presents the total number of AML-related spectra in each urine extract that was included in the cluster, c presents the total number of acquired MS2 spectra for each AML related metabolite, d total over 1 × 106 occurrences for each AML metabolite, and e shows the intensities (cts) for each AML related metabolite extracted from the LC–MS full scans using accurate mass and retention time information obtained during the node validation process, including the accurate mass for the parent drug amlodipine. An arrow is drawn to connect the annotated oxidized amlodipine (AML-OX) COOH metabolite with the corresponding peak in plot C