Liquid Extraction Surface Analysis Mass Spectrometry (LESA-MS): Examples of a New Surface Probing Technique for Clinical and Pre-Clinical Applications

Executive Summary:

  • LESA and LESAplus liquid chromatography provide novel surface analysis tools for the spatial resolution of analytes from a wide variety of surfaces.
  • Whole body or organ sections in particular can be probed for small molecules, lipids and proteins with a resolution of 400 – 1000μm.
  • Commercial solution allows for automated processing of samples (Advion TriVersa NanoMate® LESA®).

Optimization and Application of Direct Infusion Nanoelectrospray HRMS Method for Large-Scale Urinary Metabolic Phenotyping in Molecular Epidemiology

ABSTRACT: Large-scale metabolic profiling requires the development of novel economical high-throughput analytical methods to facilitate characterization of systemic metabolic variation in population phenotypes. We report a fit-forpurpose direct infusion nanoelectrospray high-resolution mass spectrometry (DI-nESI-HRMS) method with time-of-flight detection for rapid targeted parallel analysis of over 40 urinary metabolites. The newly developed 2 min infusion method requires <10 μL of urine sample and generates high-resolution MS profiles in both positive and negative polarities, enabling further data mining and relative quantification of hundreds of metabolites. Here we present optimization of the DI-nESI-HRMS method in a detailed step-by-step guide and provide a workflow with rigorous quality assessment for large-scale studies.

From the Journal of Proteome Research, Published February 2017

TriVersa NanoMate® LESA® with ESI chip® technology

The TriVersa NanoMate® LESA® is the latest in chip-based electrospray ionization technology from Advion. It combines the benefits of liquid chromatography, mass spectrometry, chip-based infusion, fraction collection and direct surface analysis into one integrated ion source platform. It allows scientists to obtain more information from complex samples than LC/MS alone.

Liquid Extraction Surface Analysis Mass Spectrometry Method for Identifying the Presence and Severity of Nonalcoholic Fatty Liver Disease

The early stages of nonalcoholic fatty liver disease (NAFLD) are characterized by the accumulation of fat in the liver (steatosis). This can lead to cell injury and inflammation resulting in nonalcoholic steatohepatitis (NASH). To determine whether lipid profiling of liver tissue can identify metabolic signatures associated with disease presence and severity, we explored liquid extraction surface analysis mass spectrometry (LESA−MS, Advion TriVersa NanoMate with LESA PLUS) as a novel sampling tool. Using LESA−MS, lipids were extracted directly from the surface of ultrathin slices of liver tissue prior to detection by high-resolution mass spectrometry (MS).

We compared the data obtained by LESA− MS to that from liquid chromatography (LC)− MS and matrix-assisted laser desorption ionization MS. Advantages of LESA− MS include rapid analysis, minimal sample preparation, and high lipid coverage.

Furthermore, since tissue slices are routinely used for diagnostics in clinical settings, LESA− MS is ideally placed to complement traditional histology. Overall LESA− MS is found to be a robust, fast, and discriminating approach for determining NAFLD presence and severity in clinical samples.

Shotgun Lipidomics Analysis

Infusion based lipidomics analysis (shotgun Lipidomics) is an analysis strategy that involves the liquid extraction of lipids from samples such as blood, tissue homogenates or dried blood spots. This approach is suitable for a wide range of biomedical questions of lipid differentiation and lipid flux in the field of metabolic disease, neurological disorders, cancers or eye diseases. See how utilizing the Advion TriVersa NanoMate® can be used for high throughput shotgun Lipidomics analysis.