FIA Flow Rate Regime

As mentioned, NBS measurement is performed without any LC separation (FIA). The injected plug is moved to the ionization source of the instrument thanks to a carrier flow supplied by an LC-pump. The duty time for acquiring the measurement is dependent on the injected volume, the flow rate, and the dispersion induced by the tubing and the dead volumes downstream the injection valve. 

I TIC from Sample 1 (050518-2) of UnBut 3.wiff (Turbo Spray) 

With some instruments this is good compromise for having a good yield at the ionization source, while for some others the source is more consistent in the attained sensitivity regardless of the flow rate regime. 

In the case of a flow rate programming, it is of paramount importance to have consistency in the appearance and duration times, e.g., starting and ending times of the plug peaks should be reproducible. Lack of it should lead to corrupted results especially in those cases where cycling between the different scanning acquisitions is performed in subsequent periods and not in simultaneous mode (see rationale in the caption of Fig. 15). 

TOTAL ION ELUTION PROFILE OF A CONTROL BLOOD SPOT Full Scan Acquisition of Acylcamitines and Amino Acids 

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