Real-Time Metabolomics on Living Microorganisms Using Ambient Electrospray Ionization Flow-Probe

Mass spectrometry sampling under ambient conditions with desorption electrospray ionization.

A new method of desorption ionization is described and applied to the ionization of various compounds, including peptides and proteins present on metal, polymer, and mineral surfaces. Desorption electrospray ionization (DESI) is carried out by directing electrosprayed charged droplets and ions of solvent onto the surface to be analyzed. The impact of the charged particles on the surface produce...

Monitoring Enzymatic Reactions in Real Time Using Venturi Easy Ambient Sonic-Spray Ionization Mass Spectrometry

We developed a technique to monitor spatially confined surface reactions with mass spectrometry under ambient conditions, without the need for voltage or organic solvents. Fused-silica capillaries immersed in an aqueous solution, positioned in close proximity to each other and the functionalized surface, created a laminar flow junction with a resulting reaction volume of ∼5 pL. The setup was op...

High-Resolution Accurate-Mass (HRAM) Phthalate Screening using Direct Analysis in Real Time (DART) Ambient Ionization

Real-time digitization of metabolomics patterns from a living system using mass spectrometry.

The real-time quantification of changes in intracellular metabolic activities has the potential to vastly improve upon traditional transcriptomics and metabolomics assays for the prediction of current and future cellular phenotypes. This is in part because intracellular processes reveal themselves as specific temporal patterns of variation in metabolite abundance that can be detected with exist...

On-line hollow-fiber flow field-flow fractionation-electrospray ionization/time-of-flight mass spectrometry of intact proteins.

Capabilities of mass spectrometry for the analysis of intact proteins can be increased through separation methods. Flow field-flow fractionation (FlFFF) is characterized by the particularly "soft" separation mechanism, which is ideally suited to maintain the native structure of intact proteins. This work describes the original on-line coupling between hollow-fiber FlFFF (HF FlFFF), the microcol...