How can I use ion mobility data to improve my compound identifications?
Ion mobility data provides us with an extra dimension to help differentiate, and identify, our compound ions. In Progenesis QI, each compound ion in a sample that was run using Waters ion mobility technology has an associated collisional cross section ("CCS") value. This value is derived from the length of time the ion takes to cross the drift cell and is represented in square ångströms (Å2), with the colliding molecule being the drift cell's N2.
During identification in Progenesis QI, each ion's CCS value can be compared against the value held in a supplementary database file — the additional properties file — to provide an extra measure of confidence in your compounds' possible identifications. You can also build up this database of known CCS values based on empirical data from your own samples, for use in future experiments.