In discovery bioanalysis, the lab is often blind to analyte structure. To proceed quickly and intelligently, we start with a default protein precipitation LC-MS/MS method that is applicable to the vast majority of small molecule compounds, eliminating the need for method development or qualification. Features of the methodology include:
Assay range of 1–5000 ng/mL (default; can be modified as required)
Front and back calibration standards consisting of nine different concentrations
Sample aliquot volume default of 10 µL of biofluid (particularly important for serial mouse sampling)
Addition of gradient selection based on retention time
The use of bracketing calibration standards is crucial in discovery to control potential divergence (drift) that can occur due to buildup of matrix components or dosing vehicle. This effort is further aided by our use of small sample volumes, which minimize these adverse effects, plus our use of the latest technologies, such as UPLC and Tandem MS (MS/MS), to achieve appropriate sensitivity even with such small sample aliquots.