A method to enumerate labile hydrogens in all constituents of molecular ensemble of natural organic matter (NOM) based on our previously developed simple hydrogen/deuterium (H/D) exchange (electrospray ionization (ESI) ion source (Kostyukevich et al. Anal. Chem. 2013, 85, 5330) and ultra-high-resolution Fourier transform ion cyclotron resonance mass spectrometry is presented. The method was app...

Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) were the result of decades of research effort dedicated toward analyzing intact biomolecules. The practicality of these ionization methods fueled the explosion of mass spectrometry witnessed in the past decade. In fact, the widespread utility of ESI and MALDI led to the awarding of the 2002 Nobel prize in Chem...

Direct analysis of polyisoprenoids by electrospray ionization mass spectrometry (ESI-MS) often produces poor results requiring off-line time and sample-consuming derivatization techniques. We describe a simple ESI-MS approach for the direct analysis of polyisoprenoids using several dolichols and polyprenols with different chain sizes as proof-of-principle cases. Lithium iodide is used to promot...

The methods of extraction, separation and analysis of alkaloids and indole glucosinolates (GLs) ofIsatis tinctoria were reviewed. Different analytical approaches such as High-pressure Liquid Chromatography (HPLC), Liquid Chromatography with Electrospray Ionization Mass Spectrometry (LC/ESI/MS), Electrospray Ionization Time-Of-Flight Mass Spectrometry (ESI-TOF-MS), and Nuclear Magnetic Resonance...

It has always been assumed that electrical contact at the capillary outlet is a necessary requirement when coupling capillary electrophoresis (CE) with electrospray ionization mass spectrometry (ESI-MS). In this study, we used a pulled bare-capillary tip as the ESI emitter, but neither was it coated with any electrically conductive materials nor was a high external voltage applied on its outlet...

Salt removal is a prerequisite for electrospray ionization mass spectrometry (ESI-MS) analysis of biological samples. Rapid desalting and a low volume connection to an electrospray tip are required for time-resolved measurements. We have developed a microfabricated desalting device that meets both requirements, thus providing the foundational technology piece for transient ESI-MS measurements o...

The approach of two different ionization techniques including electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) was tested for the analysis of cholesteryl esters (CEs). The retention time (RT), signal intensity, protonated ion, and product ion of CEs were compared between ESI and APCI. RT of C...

BACKGROUND The efficacy of lumbar percutaneous epidural neuroplasty (PEN) as a minimally invasive technique has been relatively well investigated, but the clinical effectiveness of cervical PEN (C-PEN) has yet to be established. OBJECTIVE The purpose of this study was to compare clinical outcomes between C-PEN and cervical epidural steroid injection (C-ESI). STUDY DESIGN Randomized control ...

A chip-type design asymmetrical flow field-flow fractionation (AF4) channel has been developed for high-speed separation of proteins and top-down proteomic analysis using online coupled electrospray ionization mass spectrometry (ESI-MS). The new miniaturized AF4 channel was assembled by stacking multilayer thin stainless steel (SS, 1.5 mm each) plates embedded with an SS frit in such a way that...

Large penetration of Renewable Energy Sources (RES) impacts Energy Supply Industry (ESI) in many aspects leading to a fundamental change in electric power systems. It raises a number of technical challenges to the Transmission System Operators (TSOs), Distribution System Operators (DSOs) and Wind Turbine Generators (WTG) constructors. This paper aims to present in a thorough and coherent way th...