Molecular Networking (MN) is a computational strategy that may help visualization and interpretation of the complex data arising from MS analysis.
MN is able to identify potential similarities among all MS/MS spectra within
the dataset and to propagate annotation to unknown but related molecules
(Wang et al., 2016). This approach exploits the assumption that structurally
related molecules produce similar fragmentation patterns, and therefore they
should be related within a network (Quinn et al., 2017). In MN, MS/MS data
are represented in a graphical form, where each node represents an ion with
an associated fragmentation spectrum; the links among the nodes indicate
similarities of the spectra. By propagation of the structural information within
the network, unknown but structurally related molecules can be highlighted
and successful dereplication can be obtained (Yang et al., 2013); this may
be particularly useful for metabolite and NPS identification.
MN has been implemented In different fields, particularly metabolomics And
drug discovery (Quinn et al., 2017); MN In forensic toxicology was previously
used by Allard et al. (2019) For the retrospective analysis Of routine
cases involving biological sample analysis. Yu et al. (2019) also used MN
analysis For the detection Of designer drugs such As NBOMe derivatives And
they showed that unknown compounds could be recognized As NBOMe-related
substances by MN.
In the present work the Global Natural Products Social platform (GNPS) was
exploited to analyze HRMS/MS data obtained from the analysis of seizures
collected by the Italian Department of Scientific Investigation of Carabinieri
(RIS). The potential of MN to highlight And support the identification of
unknown NPS belonging to chemical classes such as fentanyls And synthetic
cannabinoids has been demonstrated.