The nano LockSpray interface facilitates acquisition of exact mass data on electrospray time-of-flight instruments using lock mass correction whilst avoiding many of the problems associated with post-column teeing in of a reference material.
Current practice for obtaining exact mass data from a time of flight instrument is to
add a reference compound (lock mass) to the LC eluent prior to entry into the mass
spectrometer which can then be used to correct for drifts in the mass scale. There are inherent problems with this approach which can lead to poor exact mass capability:
suppression of the analyte by the reference or vice versa; mass interferences between
the analyte and reference; clustering of the analyte and reference, and variation in the reference signal strength with changes in LC gradient. In addition, the process of teeing in the reference can in some cases affect chromatographic performance.
Nano LockSpray provides the capability to introduce the reference flow through a different electrospray probe from that of the analyte and using an oscillating baffle allows analysis of each spray independently, thus avoiding the problems outlined above.