posted on 2022-01-05, 19:03authored byJade Chaker, David Møbjerg Kristensen, Thorhallur Ingi Halldorsson, Sjurdur Frodi Olsen, Christine Monfort, Cécile Chevrier, Bernard Jégou, Arthur David
Sample preparation of biological
samples can have a substantial
impact on the coverage of small molecules detectable using liquid
chromatography–high-resolution mass spectrometry (LC-HRMS).
This initial step is particularly critical for the detection of externally
derived chemicals and their metabolites (internal chemical exposome)
generally present at trace levels. Hence, our objective was to investigate
how blood sample preparation methods affect the detection of low-abundant
chemicals and to propose alternative methods to improve the coverage
of the internal chemical exposome. We performed a comprehensive evaluation
of 12 sample preparation methods (SPM) using phospholipid and protein
removal plates (PLR), solid phase extraction plates (SPE), supported
liquid extraction cartridge (SLE), and conventionally used protein
precipitation (PPT). We implemented new quantitative and qualitative
criteria for nontargeted analyses (detection frequency, recoveries,
repeatability, matrix effect, low-level spiking significance, method
detection limits, throughput, and ease of use) to amply characterize
these SPM in a step-by-step-type approach. As a final step, PPT and
one PLR plate were applied to cohort plasma and serum samples injected
in triplicate to monitor batch repeatability, and annotation was performed
on the related data sets to compare the respective impacts of these
SPM. We demonstrate that sample preparation significantly affects
both the range of observable compounds and the level at which they
can be observed (only 43%–54% of total features are overlapping
between the two SPM). We propose to use PPT and PLR on the same samples
by implementing a simple analytical workflow as their complementarity
would allow the broadening of the visible chemical space.