Methods for determining instrument linearity and quantification

A method of mass spectrometry quantitation, comprising:

• (a) providing N isomeric analytes, wherein N is an integer from 2 to 6 inclusive;
• (b) running the N isomeric analytes in two analysis runs;
• wherein a first analysis run is performed using a first series of concentrations of the N isomeric analytes and a second analysis run is performed using a second series of concentrations of the N isomeric analytes interleaved in concentration with the first series of concentrations of the N isomeric analytes;
• (c) determining an instrument response versus concentrations of the N isomeric analytes;
• and,
• (d) quantifying an isomer based on the response versus concentrations of the N isomeric analytes.

A kit for determining mass spectrometer linearity, comprising:

• (a) providing N isomeric analytes, wherein N is an integer from 2 to 6 inclusive;
• (b) running the N isomeric analytes in two analysis runs;
• wherein a first analysis run is performed using a first series of concentrations of the N isomeric analytes and a second analysis run is performed using a second series of concentrations of the N isomeric analytes interleaved in concentration with the first series of concentrations of the N isomeric analytes;
• and,
• (c) determining an instrument linearity indicator value from a plot of mass spectrometry response versus concentrations of the N isomeric analytes, wherein the instrument linearity indicator value denotes a critical operating linearity characteristic of a mass spectrometer.