Introducing the MSQ
The Source–An Introduction to API Techniques ________________________________________________
The Source–An Introduction to API
Techniques
The source, or interface, performs four main functions:
Separates the analytes from the solvent and buffer systems used in LC
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Ionizes the analyte molecules
Allows efficient transfer of ions into the mass analyzer for detection
LC eluent enters the source through the orthogonal sample introduction
probe. The primary objective of an orthogonal probe is to direct any
involatile components present in the LC eluent, such as those from buffers,
ion-pairing agents, or matrices, away from the entrance orifice. Under
operating conditions, however, both the sample ions and the charged liquid
droplets (containing any involatile components, if they are present) are
deflected by the electric field towards the entrance orifice. This leads to a
gradual buildup of involatiles and a concomitant loss in sensitivity with
time. The self-cleaning source delivers a constant, low flow of solvent (the
cone wash™) to the edge of the inlet orifice, helping to prevent a buildup of
involatiles during an LC/MS run.
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___________________________ MSQ Hardware Manual ____________________________