Ion mobility spectrometry (IMS) is a rapid, orthogonal, gas phase separation technique that provides another dimension of separation within an LC timeframe, allowing compounds to be differentiated based on size, shape, and charge. In addition, precursor ions (with isotopes), fragment ion information, and Collision Cross Section (CCS) values can be acquired in a single acquisition.
In food and environmental analysis one of the major challenges is the variety of sample matrices encountered and overcoming the subsequent analytical matrix effects. One of those matrix effects is the presence of components in the matrix that can interfere with the confirmation and identification of target compounds and unknowns. Typically mass spectra are generated by integrating chromatographic peaks using a variety of peak detection algorithms, then extracting a representative spectrum at the retention time corresponding to the maximum intensity of the peak. Complex mixed mass spectra are often generated when matrix components co-elute with the compound of interest. To attempt to overcome this, background subtraction routines are often used with varying success, depending on the complexity of the sample.
Figure 1 shows the conventional retention time aligned precursor and fragment ion spectra for thiabendazole (m/z 202) generated using 3D peak detection algorithm within UNIFI Software, which typically generates cleaner spectra compared to other available peak detection algorithms. Many other ions can be seen in the spectrum, particularly above the ion corresponding to thiabendazole (m/z 202).
