As part of the explosion of knowledge and potential applications to human health that the “omics” revolution has provided us, the realization that sole focus upon any one area of study therein will not lead to a full capitalization upon the potential opportunities that omics present us with.
In the field of metabolomics, as with other disciplines, the need to understand biological processes at ever increasing levels of detail, often from complex matrices, and to do so faster, with greater precision and specificity, has driven significant research effort into the design and development of suitable sample introduction methods into today’s most advanced analytical instrumentation.
The present study is one example of such an effort, wherein the authors developed and studied a direct infusion probe method of sample introduction for mass spectrometric analysis of intracellular metabolism of insulin secreting INS-1 cells and the effect of glucose exposure thereon. The results support exploration of the potential widespread applicability of this approach to chemically complex samples comprised of low number of cells and small sample volumes. Link to the study in Analytical Chemistry, below.
Catia Marques, Liangwen Liu, Kyle D. Duncan, and Ingela Lanekoff
September 7, 2022
Targeted and nontargeted metabolomics has the potential to evaluate and detect global metabolite changes in biological systems. Direct infusion mass spectrometric analysis enables detection of all ionizable small molecules, thus simultaneously providing information on both metabolites and lipids in chemically complex samples. However, to unravel the heterogeneity of the metabolic status of cells in culture and tissue a low number of cells per sample should be analyzed with high sensitivity, which requires low sample volumes. Here, we present the design and characterization of the direct infusion probe, DIP. The DIP is simple to build and position directly in front of a mass spectrometer for rapid metabolomics of chemically complex biological samples using pneumatically assisted electrospray ionization at 1 μL/min flow rate. The resulting data is acquired in a square wave profile with minimal carryover between samples that enhances throughput and enables several minutes of uniform MS signal from 5 μL sample volumes. The DIP was applied to study the intracellular metabolism of insulin secreting INS-1 cells and the results show that exposure to 20 mM glucose for 15 min significantly alters the abundance of several small metabolites, amino acids, and lipids.
Innovative Research Product used in study: Innovative Grade US Origin Rat Sprague Dawley Brain