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Nguyen, Son N.

Publications and source records attributed to Nguyen, Son N..

Techniques for controlling distance between a sample and sample probe while such probe liberates analyte from a sample region for analysis with a mass spectrometer

A system includes a mass spectrometer and associated sample interfacing equipment. The sample interfacing equipment includes a platform structured to support a sample thereon, a fluid source, a high voltage source, a dispensing probe electrically coupled to the high voltage source and defining a fluid dispensing passage therethrough, a collection probe defining a collection passage therethrough, a sensing arrangement coupled to the dispensing probe, and control logic responsive to the sensing arrangement to control distance between the dispensing probe and the sample. The dispensing probe facilitates formation of one or more ionized sample analytes when dispensing the fluid through the dispensing passage proximate to the sample on the platform. The collecting probe receives at least some of the one or more ionized sample analytes to pass through the collection passage into the mass spectrometer for analysis.

47 OTHER INSTRUMENTATION↗

Towards High-Resolution Tissue Imaging Using Nanospray Desorption Electrospray Ionization Mass Spectrometry Coupled to Shear Force Microscopy

Constant mode ambient mass spectrometry imaging (MSI) of tissue sections with high lateral resolution of better than 10 μm was performed by combining shear force microscopy with nanospray desorption electrospray ionization (nano-DESI). Shear force microscopy enabled precise control of the distance between the sample and nano-DESI probe during MSI experiments and provided information on sample topography. Proof-of-concept experiments were performed using lung and brain tissue sections representing spongy and dense tissues, respectively. Topography images obtained using shear force microscopy were comparable to the results obtained using contact profilometry over the same region of the tissue section. Variations in tissue height were found to be dependent on the tissue type and were in the range of 0–5 μm for lung tissue and 0–3 μm for brain tissue sections. Ion images of phospholipids obtained in this study are in good agreement with literature data. Normalization of nano-DESI MSI images to the signal of the internal standard added to the extraction solvent allowed us to construct high-resolution ion images free of matrix effects. .

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Lipidomics reveals dramatic lipid compositional changes in the maturing postnatal lung

Lung immaturity is a major cause of morbidity and mortality in premature infants. Understanding the molecular mechanisms driving normal lung development could provide insights on how to ameliorate disrupted development. While transcriptomic and proteomic analyses of normal lung development have been previously reported, characterization of changes in the lipidome is lacking. Lipids play significant roles in the lung, such as dipalmitoylcholine in pulmonary surfactant; however, many of the roles of specific lipid species in normal lung development, as well as in disease states, are not well defined. In this study, we used liquid chromatography-mass spectrometry (LC-MS/MS) to investigate the murine lipidome during normal postnatal lung development. Lipidomics analysis of lungs from post-natal day 7, day 14 and 6-8 week mice (adult) identified 928 unique lipids across 21 lipid subclasses, with dramatic alterations in the lipidome across developmental stages. Our data confirmed previously recognized aspects of post-natal lung development and revealed several insights, including in sphingolipid-mediated apoptosis, inflammation and energy storage/usage. Complementary proteomics, metabolomics and chemical imaging corroborated these observations. Finally, this multi-omic view provides a unique resource and deeper insight into normal pulmonary development.

59 BASIC BIOLOGICAL SCIENCES↗

Enabling Re-executable Workflows with Near-realtime Visualization, Provenance Capture and Advanced Querying for Mass Spectrometry Data

Mass spectrometry imaging (MSI) enables simultaneous spatially-resolved analysis of numerous ionizable molecules on a sample surface. The current analysis pipeline involves analyzing the data coming off the instrument using a tool called MSI Quickview and saving the results onto a storage drive before moving on to the next experiment. While this works well for single datasets, there is a demand for more scalable, flexible workflows that are re-executable across datasets, support extensive querying and ease collaboration. Here, we present a workflow that moves data analysis from a mere desktop application for single experiments to a more general capability

Re-executable workflow↗