Evaluation of critical instrument parameters for the transfer of LC-MS quantification methods between LC-MS/MS and Orbitrap MS

Sammanfattning: Transferring analytical methods is crucial in chemical laboratories. The need for the transfer may arise for different reasons such as sharing data between different laboratories, replacement or upgrade of analytical instrument, or limited instruments available etc. The performance and sensitivity of different instruments may vary. Three LC-MS instruments of two different manufacturers were used to identify critical parameters that might affect signal intensity. The instruments included in this study were two tandem mass spectrometers (Waters Acquity® TQD MS and Waters Xevo® TQSμ MS) and an orbitrap mass spectrometer (Thermo Scientific Q Exactive Focus). The capillary and cone voltages of selected model compounds were optimized prior to linearity study. The linearity study was performed in order to examine the dynamic range of the instruments. Limits of detection and quantitation were also evaluated. Different instrument settings were tested in order to evaluate and compare the impact of different MS parameters on the signal intensity of the selected model compounds. Thermo Scientific Q Exactive Focus was observed to be less sensitive to different settings. An existing analytical method for fluoxetine (ESI+) and bisphenol A (ESI-) was transferred from Waters Xevo® TQSμ MS to Thermo Scientific Q Exactive Focus; the performance of Waters Xevo® TQSμ MS and Waters Acquity® TQD MS was compared by using the same analytical method on both instruments. The results showed that LOD and LOQ were higher for Waters Acquity® TQD MS than for Waters Xevo® TQSμ MS. Additionally, the method transfer resulted in similar LOD and LOQ values for fluoxetine and bisphenol A on Waters Xevo® TQS micro MS and Thermo Scientific Q Exactive Focus. In case high sensitivity is not a requirement of an analysis, a set of standard settings as the ones used in this study may be sufficient during a method transfer between Waters Acquity® TQD MS and Thermo Scientific Q Exactive Focus.