question about MassLynx

<p>I'm glad Hoth asked the question about other communities. I have a question about MassLynx. I know this is not directly related to UPLC. I just hope if there is any one can give me some hint.</p><p style="height: 8pt"/><p>Is there any software compatible with MassLynx that can measure peak width (at a given peak height), peak symmetry, peak tailing factor, colum plate number, etc.? I don't have any internal standard to compare with.</p><p style="height: 8pt"/><p>Thank you.</p>

Answers

  • When I need to do this, I bring the data into Empower II. There may be other ways and other software but I am not aware of them.
  • Currently MassLynx can give you Kurtosis which is Assymetry but you cannot get plate count, peak resolution Ki alpha etc. With 627 and TargetLyxn you get a few functions that are close to interactive suitability

    Many users bring the data into Empower. We will keep asking some more users and add to the advice about Empower

    If we can find an answer we will certainly post.

    Liz

    Edited by: Elizabeth Hodgdon on Jan 27, 2009

  • I believe you can import the UV data to Empower, which has an optional module that can calculate those parameters. Please double check with Waters Tech Support or your local Waters representative. I am planning to control the UPLC with Empower for its superior UV data handling capability and send a contact closure signal to Synapt and MassLynx to collect MS data. In addition, the UV data is going to be sent to MassLynx from Empower through a eSAT/IN module (to be installed by Waters engineer this Thurs) to align with the MS data.

    Hope this may help.

  • To clarify further TargetLynx can give:

    Pk Kurtosis: degree of peak flatness. Pointed peaks have positive values, flat peaks have negative values, Guassian peaks have zero kurt.
    Pk Skew: degree of peak asymmetry. A positive value indicates a tail extending to positive values, a negative value indicates a tail extending to negative values.
    Pk Width: peak width (in seconds) at half height

    The method can be setup with predicted values and thresholds so that the peaks are flagged if they fall outside the expected ranges.
    Or these values can be measured in user-specified Ref samples, averaged, and then the software will compare the analyte peak quality with the Ref peak values

  • Greetings Cindy,

    I know that baseline peak width is available in QuanLynx. I have used this before to gain information on some of the questions you, also, seem to be trying to answer.

    Regards,

    pcb

  • Dear Cindy,

    There is a simple way to calculate the plate count in both QunLynx and TargetLynx. By using the formula fields (a simplified version of custom fields in Empower) one can calculate plate count N, according to:

    Theoritical plates: N = 5,54 * ( t / W 0.5)2

    waarin N = theoritical plates
    t = retention time of the component
    W 0.5 = width of peak at the position of 50% peak hight..

    Peak width can be measured at baseline and at half height.

    I have posted an example report of a small system suitability test.

    For more detail do not hesitate to contact me via email: marijn_van_hulle@waters.com.

    Regards,

    Marijn Van Hulle

    MS sales and applications specialist, Belgium