This application note describes the analysis of the three pharmaceutical drugs using four sample extraction protocols; protein precipitation, Oasis MCX and Oasis PRiME MCX (3-step) and Oasis PRiME MCX (4-step) to compare analyte recovery and matrix effects including phospholipid removal.
Oasis PRiME MCX (3-step) and Oasis PRiME MCX (4-step) sample preparation protocols remove 98% of phospholipids compared to protein precipitation, while, providing reproducible results and cleaner extracts (less than -10% matrix effects). This is an improvement on the Oasis MCX sample extraction protocol which only removes 86.6% of the phospholipids but has comparable precision and % recovery with -17.2% matrix effects.
Even though protein precipitation is an inexpensive form of sample preparation, the matrix effects indicate that inefficiencies (poor recovery and high matrix effects) of the sample clean-up which may lead to poor robustness of the bioanalytical method.
The μElution format with the Oasis PRiME MCX Protocols enable a faster workflow, through the use of a simplified protocol and direct injection of the plasma extract without the need for evaporation or reconstitution. This SPE format and extraction protocol can be easily automated using a liquid handling robot to improve laboratory workflow, eliminate transcription errors, and allow for sample tracking capabilities.