As part of the kit lot verification process, we compare the calibrator for the new kit lot to a reference calibrator lot in order to assign a concentration to the new calibrator lot. We report the measured concentration for the new calibrator lot. For example, if there is a 10% difference between the new and the reference calibrator lots, then the stock concentration for the two calibrator lots would be different by 10% and the top of the standard curves would change accordingly. This means that when you measure the same sample/control across kit lots, you get a consistent measured concentration.

Each MSD toxicology assay kit is provided with a COA that includes the calibrator concentration specific to that kit and the representative standard curves.