Data Analyses @MassHunter Quantitative Software

[SN1985]

Hello Everyone,

I am a newbie to Chromatography - Mass Spectrometry field and have started processing data using Agilent MassHunter Quantitative Software. I have three queries.
1. I have found out there are 4 options to get the calibration curve where i. origin = ignore, ii. origin = include, iii. origin = force and iv. origin = offset. My question is what is/are the criteria to pass the calibration curve?
2. Is there any contribution of the relative response of qualifier(s) of the target and ISTD in the quantitation process?
3. Is there a way to manually enter the relative response of qualifier(s) in the quantitation method if it doesn't get picked up automatically from the data file?

Thanks in advance!

[millerk8561]

1. I have found out there are 4 options to get the calibration curve where i. origin = ignore, ii. origin = include, iii. origin = force and iv. origin = offset. My question is what is/are the criteria to pass the calibration curve?

Inclusion/Exclusion of the origin, to quote my favorite Agilent instructor, is "dependent upon your regulatory environment." For example, PFAS testing EPA Method 537.1 I believe requires you to force through zero and DoD/QSM 5.3 guidelines for PFAS testing say the opposite (ignore origin). I would defer to the judgment of your Laboratory Director if there's no explicit guidelines, because different schools of thought exist (with the worst of them being "whatever makes it pass" ). Also, pass/fail is regulatory environment and Laboratory QA dependent, with varying rules about dropping calibration curve points, what constitutes a passing r^2 value, etc.

[James_Ball]

Hello Everyone,

I am a newbie to Chromatography - Mass Spectrometry field and have started processing data using Agilent MassHunter Quantitative Software. I have three queries.
1. I have found out there are 4 options to get the calibration curve where i. origin = ignore, ii. origin = include, iii. origin = force and iv. origin = offset. My question is what is/are the criteria to pass the calibration curve?

As above, too many different regulatory agencies to give a definite answer. If not in a regulated field, then what gives the best fit to the curve and quants back closest to the true value of each standard.

2. Is there any contribution of the relative response of qualifier(s) of the target and ISTD in the quantitation process?

No. Qualifiers are qualitative only, used to assess if the peak is truly what it is.

3. Is there a way to manually enter the relative response of qualifier(s) in the quantitation method if it doesn't get picked up automatically from the data file?

Yes. In the area where you can manually add a qualifier, there is a ratio or % field that you can manually enter the relative abundance % match criteria, both the expected % and the amount of error allowed for a positive match.

Thanks in advance!