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How to Eliminate LC-MS Interference Peaks and Chemical Background: Improving the Limit of Quantitation for THC-COOH in Hair

  • Duration: 1 hr
  • Date:MAY.16.2018 1:00 PM - 02:00 PM

Price: $0.00

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Visit Sciex Diagnostics to learn more about efficiency, automation, usability, and optimized workflows.

This webinar program is brought to you by Sciex Diagnostics. The contents of this program were developed by Sciex Diagnostics, independently of AACC.  


With its high specificity and sensitivity, laboratorians know liquid chromatography-tandem mass spectrometry (LC-MS/MS) as the gold standard for quantifying small molecule drugs and drug metabolites. However, alternative matrices like hair and oral fluid present unique challenges. These can include interference peaks and chemical background that limits the ability to measure low concentrations. Even high-resolution mass spectrometry may face limitations, such as when interferences have the same mass as the target compound.

To deal with these problems, clinical laboratories are now using multistage fragmentation (MRM3) to improve sensitivity. This presentation will explain how MRM3 quantitation can improve the limit of quantitation down to 0.1 pg/mg of the metabolite 11-nor-9-Carboxy-THC in hair.


  • How you can reduce LC-MS/MS for sample prep with alternative matrices such as THC-COOH in hair
  • How MRM3 increases efficiencies in chromatography
  • How reducing the Limit of Quantification (LOQ) using MRM3 can improve chromatography quantification of THC-COOH 


Holly McCall_Sciex May 16_2018_Webinar

Holly McCall, PhD
Application Support Scientist, SCIEX



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