LC-MS/MS is an important technique for small molecules bioanalysis in DMPK studies. Although LC-MS/MS produces highly sensitive, specific and reproducible data, throughput can be a limitation and this can lead to a bottleneck in the PK screening process.
To address this challenge, Cyprotex have developed and evaluated the use of Ultra-fast Separation Chromatography to improve the efficiency of sample analysis in small molecule PK studies. This efficiency was achieved by optimising the speed of the chromatographic separation without compromising retention and resolution. Separation is achieved using a linear gradient elution on short chromatographic columns of conventional selectivity mounted close to the MS ion source to minimise post column band broadening. Using this rapid separation method, it was possible to reduce the chromatographic run time from 108 sec to 30 sec equating to a potential 3.6-fold increase in throughput. Plasma and blood samples from a pharmacokinetic study were analysed by the rapid separation method and compared to conventional column technology. From the resulting PK profile, parameters such as clearance, volume of distribution, AUC, half-life, Cmax, tmax, bioavailability were determined.
Prior to sample analysis, the column performance was assessed using a set of 5 standard compounds. The developed rapid separation method achieved consistent results with all data quality parameters being met. After qualification of the method, PK study samples were analysed to examine chromatographic quality and potential ion suppression/enhancement in biological matrices. The biological samples were prepared by protein precipitation. Spiked quality control sample precision and accuracy were demonstrated at low, medium and high concentrations and linearity was demonstrated (r2 =0.99) over the calibration range. The pharmacokinetic parameters exhibited excellent agreement between the rapid separation method and conventional separation method for both the plasma and the blood samples.
This research was presented as a poster at the European Bioanalysis Forum (EBF) in November 2022 in Barcelona. Read our poster to learn more about this research.