Implementation of ETD Reactions in a Linear Quadrupole Collision Cell Utilizing a Static DC Gradient for Dual Ion Trapping

摘要

The presented experimental mode of operation uses the partial overlap in a Z-shaped trapping potential for ion/ion reactions in a linear quadrupole trap. Cations and anions could be detected which shows that dual trapping can be achieved with the presented implementation of this method. The measured fragmentation efficiencies are similar to those measured in the LTQ linear trap using charge sign-independent trapping. Also, the obtained fragmentation patterns look very similar to those measured with the default method. Thus, we can rule out the possibility of collision-induced dissociation, which would generate a very different fragmentation pattern. The presented mode of operation shows a similar performance to the charge sign-independent trapping method in the LTQ. But the technical complexity is lower because the presented method requires neither an additional RF generator for the end lens nor a segmented ion trap. In comparison to passing reactions, the reaction rate is much higher because much higher anion densities can be achieved. Furthermore, both ion populations are thermalized which also increases the reaction rate.