The application of different sample preparation techniques to improve LC-MS based assay performance

Learn New Targeted Workflows to Overcome Challenges in Biomolecule Characterization Liquid chromatography coupled with mass spectrometry (LC-MS) is a highly specific, sensitive and rapid technique that can be used for the determination of low-level target analytes in complex matrices, such as biological fluids, food products and also environmental samples. Injection of neat matrices onto the LC-MS system is typically not practical as this would result in a plethora of issues including, but not limited to:

• Particulate build up on the column, resulting in increased back pressure
• Back pressure build up/blockage due to matrix components precipitated in the mobile phase
• Contamination of the column, resulting in poor peak shape and retention time shifts
• Contamination of the LC-MS instrumentation causing sensitivity and carryover issues
• Ion suppression issues associated with coelution of matrix components with the analyte of interest

These issues are highly undesirable, particularly in high throughput scenarios, as they result in significant reduction in chromatographic performance and column lifetime, more frequent instrument down-time and increased instrument maintenance and cleaning requirements, as well as impacting the quantitative robustness of the assay. This presentation will look at a range of sample preparation techniques, including protein precipitation, supported liquid extraction (SLE) and solid phase extraction (SPE), which will address the issues mentioned previously.

The presentation will provide an insight into the to understand how these different techniques work, and how they can be successfully applied to analysing biological fluids. Workflows will be presented that detail how to choose between the different approaches, and with SPE providing an understanding of which stationary phase to select, and how to optimise the methodology. Examples will be provided that demonstrate that a generic approach to method development can be successfully applied, based on an understanding of the physiochemical properties of the analytes.

Presenter: Matt James

Matt James is a Senior Research Scientist at Avantor Sciences. Matt gained his PhD at University of Bristol, working on the analysis of archaeological samples and also worked within the pharmaceutical industry for a year. Over the last 11 years, he has worked within the Technical Support, Applications and R&D teams within Hichrom, now part of Avantor. Recent focuses have been HPLC/UHPLC method transfer and translation, the use of solid core phases, development of next generation LC stationary phases and the development of LC methods for key applications, such as the analysis of nitrosamines by LC-MS/MS. Matt has co-authored seven peer reviewed articles and presented work at several conferences.