A HPLC-DAD-MSD instrument is highly powerful in the characterization of unknown compounds. It separates molecules on a HPLC column, gives absorption spectra for each peak and a corresponding mass in positive and negative mode, mostly all within 10 min.
The instrument is specifically powerful in its fast switching between positive and negative mode, which gives the most quick insight into important characteristics of the molecule as functional groups. It requires chemical knowledge to interpret the combination of different spectra and confirmation using databases of known compounds, but for that interpretation you are at the right place here. In a second step, the compound can be further confirmed with high-resolution mass spectrometry, providing a mass accuracy < 1ppm and a bruto formula (like e.g. C8H10O3N).
