Force biphenyl column

Target analytes were analyzed using Agilent 1290 Infinity II LC System coupled to Agilent 6460 Triple Quadrupole mass spectrometer (Santa Clara, CA). Analytes were separated using methanol and a 0.1% aqueous solution of formic acid (Table S1) through a Force Biphenyl column (100 mm × 2.1 mm × 1.8 μm) (Thermo Fisher Scientific, Waltham, MA). Identification of analytes was based on retention time (±0.05 min), quantitative and qualitative m/z ion transitions (Table S2) in positive ionization mode, and a relative abundance of qualitative to quantitative ions (±20%). Analytes were quantified based on an isotopic dilution method of quantification. The calibrations curves were prepared by plotting concentration-dependent response factor of each analyte (peak area of analyte divided by peak area of internal standard) versus the response-dependent concentration factor (concentrations of analyte divided by the concentration of internal standard). The regression coefficients (r²) for five- to ten-point calibration standards calculated by linear regression were ≥0.99 for all analytes.

Target analytes were analyzed using Agilent 1290 Infinity II LC System coupled to Agilent 6460 Triple Quadrupole mass spectrometer (Santa Clara, CA). Analytes were separated using methanol and 0.1% aqueous solution of formic acid (Table S1) through a Force Biphenyl column (100 mm × 2.1 mm × 1.8 μm) (Thermo Fisher Scientific, Waltham, MA). Identification of analytes was based on retention time (±0.05 min), quantitative and qualitative m/z ion transitions (Table S2) in positive ionization mode, and a relative abundance of qualitative to quantitative ions (±20%). Analytes were quantified based on an isotopic dilution method of quantification. The calibrations curves were prepared by plotting concentration-dependent response factor of each analyte (peak area of analyte divided by peak area of internal standard) versus the response-dependent concentration factor (concentrations of analyte divided by the concentration of internal standard). The regression coefficients (r²) for five- to ten-point calibration standards calculated by linear or quadratic regression were ≥0.99 for all analytes.