Abstract: A targeted quantitation system for mass spectrometry may acquire, while operating in a watch mode, a watch mode mass spectrum including mass peaks for ions produced from a plurality of internal standard variants added to a sample comprising a target analyte. Each internal standard variant included in the plurality of internal standard variants includes a unique isotopologue of the target analyte and is added to the sample in a unique amount. The targeted quantitation system may generate a calibration curve based on the watch mode mass spectrum. The targeted quantitation system may acquire, while operating in a quantitation mode, a quantitation mode mass spectrum including mass peaks for ions produced from the target analyte included in the sample. The targeted quantitation system may determine a concentration of the target analyte included in the sample based on the calibration curve and the second mass spectrum.

Abstract: A targeted quantitation system for mass spectrometry may acquire, while operating in a watch mode, a watch mode mass spectrum including mass peaks for ions produced from a plurality of internal standard variants added to a sample comprising a target analyte. Each internal standard variant included in the plurality of internal standard variants includes a unique isotopologue of the target analyte and is added to the sample in a unique amount. The targeted quantitation system may generate a calibration curve based on the watch mode mass spectrum. The targeted quantitation system may acquire, while operating in a quantitation mode, a quantitation mode mass spectrum including mass peaks for ions produced from the target analyte included in the sample. The targeted quantitation system may determine a concentration of the target analyte included in the sample based on the calibration curve and the second mass spectrum.