Custom field with standard average area

I would like to create a custom field that would use the average of standards area... Empower already has this field? Or I would need to create it? If yes, how I create it?

Answers

  • Hi... PLEASE check why you are looking for this field. If it is to calculate a Response factor for doing quantitation, PLEASE DON"T use custom fields for this. Empower already has that capability, to average the response of all Stds of the same AMOUNT, or of the same level, and calculate, through a calibration curve, the amount in you samples.
  • No, It is not for regular calculations, I use it in routine. Now I have two active ingredients and I will need to calculate the sum of it areas in the sample (unknown) divided by the average of standards area... It is for method validation purpose (sorry for my bad english : ) )
  • HeatherLongden
    edited January 2019
    I still believe you can leverage the regular quantitation process to do this... 
    Dividing the areas in the sample by the average of the stds is exactly what quantitation does. Adding two peaks together ( to treat them as one group peak) is also a std Empower functionality.
  • You say you have 2 peaks of interest and multiple injections which you want to average.  Maybe it would help if you outline the mathematical calculation for us and include some example data? That will help identify if it matches a built-in field and exactly which field it is versus requiring a custom field and the help you might need creating it.
  • Average of standard areas is already done as part of the Amount Empower field. You just have to set up your sample types and labels/component editor as appropriate. Is your calculation of the type (Peak Area Sample/Average Peak Area of Bracketing Standards)?
  • Ok, maybe I just do not know where it's at empower:
    I have two peaks that I'm already treating as a group peak, let's say P1 (peak 1) + P2 (peak 2) = G1 (group peak). I need this simple answer: G1area in unknown samples / G1 area in standard samples.
    I do not think this is the answer returned by Amount column. I'm checking calculations in an excel sheet.
    Where in Empower help can I see what calculations does each field?
  • Amount will do what you are looking for but you need to adjust the "Source of Calibration X Value" option in the Named or Group Peaks tab of the processing method. Set it to User Entered, Curve or Sum Peaks for quantitation then in your sample set make sure the standard is set to Inject Standard and your sample is set to Inject Samples. Label the Standard as S, the sample as U then directly under your sample, enter Clear Calibration, then Calibrate (with the label reference for Calibrate set to S) then select Quantitate and have the label reference for that as U. Then process your sample set and you will get an amount value for G1 which is the same as what you are looking for. 
  • If Dilution, Sampleweight and STD amount are all set to one, the regular Empower quantitation of AMOUNT is simply a ratio of the areas.