difference between full loop mode and PLNO

AureliaClementz
AureliaClementz
in Instrumentation and Mass Spectrometry
I have a question regarding the impact of use of full loop mode vs PLNO. My reverse-phase method was qualified in full loop-mode but in my lab the loops are qualified only in PLNO mode. That means I cannot use the method as qualified in my lab. However I believe what is important is the volume injected, right? in my lab we will inject 2 ul with a 10ul sample loop in PLNO mode, while in the QC lab they will inject 2ul with 2ul sample loop and full loop mode. Both loops were shown to be qualified to inject 2ul accurately. Are there any other important parameters that would have an influence on the method performance and generated results?

Answers

  • Jovvor
    Jovvor
    https://www.waters.com/webassets/cms/support/docs/715002108rA.pdf

    This document provides a good overview for the differences in injection modes.

    The volume injected for a full loop injection is never precise the volume of the loopsize.
    So when you have a method with PLNO and go to a system with a full loop method, it is possible you will inject more (or less) than the 2ul. It can be a 22% difference for smaller size loops... (as read in the document).

    I would not recommend going from PLNO to Full loop injections due to the possible volume difference.




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