Direct plasma sample injection in multiple-component LC-MS-MS assays for high-throughput pharmacokinetic screening

Area of Science:

• Analytical Chemistry
• Pharmacokinetics
• Drug Discovery

Background:

• High-throughput drug screening relies on simultaneous dosing and multi-component analysis (N-in-1 approach) using LC-MS-MS.
• Traditional plasma sample extraction is a bottleneck, limiting assay throughput in drug screening.
• N-in-1 LC-MS-MS assays require high sensitivity and excellent chromatographic separation to minimize interference and suppression effects.

Purpose of the Study:

• To develop a high-throughput on-line extraction technique for multiple-component LC-MS-MS assays.
• To enable direct plasma sample injection, bypassing traditional extraction limitations.
• To meet the high sensitivity and chromatographic separation requirements for N-in-1 LC-MS-MS assays in pharmacokinetic screening.

Main Methods:

• Development of a high-flow column-switching technique for on-line extraction.
• Direct injection of plasma samples containing multiple drug candidates onto an extraction column.
• Utilized turbulent-flow conditions for faster, more rugged extraction with reduced carryover.
• Elution of extracted analytes onto an analytical column for LC-MS-MS analysis via column switching.

Main Results:

• The turbulent-flow column-switching technique achieved high sensitivity and excellent chromatographic separation.
• Performance metrics (separation efficiency, dynamic range, accuracy, precision) were comparable to solid-phase extraction.
• Demonstrated reduced carryover and increased ruggedness compared to laminar-flow conditions.

Conclusions:

• The developed direct plasma injection method effectively addresses throughput limitations in N-in-1 LC-MS-MS assays.
• This turbulent-flow column-switching technique is suitable for high-throughput pharmacokinetic screening.
• The method successfully meets the stringent requirements for sensitivity and separation in complex biological matrices.