Triple quadrupole systems neutral loss scanning

The most common modes of operation for ms/ms systems include daughter scan, parent ion scan, neutral loss scan, and selected reaction monitoring. The mode chosen depends on the information required. Structural identification is generally obtained using daughter or parent ion scan. The mass analyzers commonly used in tandem systems include quadrupole, magnetic-sector, electric-sector, time-of-flight, and ion cyclotron resonance. Some instmments add a third analyzer such as the triple quadrupole ms (27). 

In neutral loss scan, all precursor ions, which lose a particular neutral particle (that otherwise cannot be detected in MS), are detected. Both mass analysers scan, but with a constant selected mass difference, which corresponds to the mass of the neutral particle lost. This analysis technique is particularly meaningful if molecules contain the same functional groups (e.g., metabolites as acids, glucuronides or sulfates). In this way, it is possible to identify the starting ions which are characterized by the loss of a common structural element. Both MS/MS scan techniques can be used for substance-class-specific detection in triple quadrupole systems. Ion trap systems allow the mapping of these processes by linking the scans between separate stages of MS in time. 

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