UPLC I-Class FTN vs. Fixed Loop injection

<p>Hi,</p><p></p><p>What are the the major differences between the I-Class Sample Manager with FTN (flow through needle) and FL (fixed loop) injection? What are the cons and pros in different situations?</p><p></p><p>Hope someone can enlighten me.</p><p></p><p>Kind regards</p><p>Rasmus</p>


  • Hi Rasmus

    The I-Class FL is configured with a fixed loop injector like the "original" ACQUITY system, but with a lot of improvements. The FTN is a flow through needle injector design, like the one in the ACQUITY H-Class system, but again with improvements. The FL has a slightly lower total system volume (95 ul versus 100 ul for the FTN). The carryover specs for the FTN is slightly lower than than the FL (0.001% vs 0.002%).

    The FL has 3 different injection modes the FTN only 1.

    System bandspreading is <7ul for FL and <9ul for FTN.

    Shortest cycle time with the FL.

    If you plan to use 1mm ID columns the FL is better because of the lower volume.

    So all in all it depends much on your applications which version to choose.

    Hope this helps a little.

    best regards


  • Hi Rune,

    Thanks for the information, it was helpfull.

    I have a few more questions. What about sample comsumption. Are there any differences between FTN and FL regarding this?

    My experience with the original AQUITY system is that it uses a relatively large amount of sample pr. injection (depending on the Full Loop overfill factor). I use 10 µl full loop injection.

    Do you know which system is most suited for injecting different sample amouts? For instance when you are switching between two methods with 5 and 10 µl injection. This must be PLNO on the Fixed Loop sample manager? But how is this handled on the FTN system?

    Thanks again.

    Kind regards


  • Hi Rasmus

    This is one thing I forgot to mention as a difference so good that you brought this up. The FTN only uses (draws) the amount you have specified, so no sample loss. The FL again is the same as the "original" ACQUITY it works with an overfill factor for full loop and also a needle overfill volume for PLUNO injections, so it will waste some sample.

    In your case I would recommend the FTN version of the I-Class.

    Best regards


  • Hi Rune,

    Thanks a lot for your help.