Ultrahigh-Performance Supercritical Fluid Chromatography–Multimodal Ionization–Tandem Mass Spectrometry as a Universal Tool for the Analysis of Small Molecules in Complex Plant Extracts

Abstract

Complex analysis of plant extracts usually requires a combination of several analytical approaches. Therefore, in this study, we developed a holistic two-injection approach for plant extract analysis, which is carried out within one instrument without the need for any manual intervention during the analysis. Ultrahigh-performance supercritical fluid chromatography (UHPSFC) was employed for the analysis of 17 volatile terpenes on a porous graphitic carbon column within 7.5 min, followed by analysis on short diol column where flavonoids, phenolic acids, and terpenoic acids were analyzed within 15.5 min. A multimodal ionization source combining electrospray and atmospheric pressure chemical ionization (ESCi) was selected for mass spectrometry detection as a simultaneous ionization of both lipophilic and polar compounds was required. The quantitative aspects of the final UHPSFC-ESI/ESCi-MS/MS twoinjection approach were determined, and it was applied to the analysis of Eucalyptus sp. extracts prepared by supercritical fluid extraction. Current methods reported in the literature typically require a labor-intensive combination of liquid and gas chromatography for the complex analysis of plant extracts. We present for the first time a new UHPSFC approach requiring only a single instrument that provides an alternative approach to the analysis of complex plant extracts.

Comprehensive two-step supercritical fluid extraction for green isolation of volatiles and phenolic compounds from plant material

“…Two ultra-high performance supercritical fluid chromatography-tandem mass spectrometry (UHPSFC-MS/MS) methods published by Plachká et al 33 were used and are briefly summarized here. All experiments were carried out using an Acquity UPC 2 supercritical fluid chromatography system (Waters, Milford, MA, USA) with a binary pump, an autosampler, a column thermostat, a BPR, and a PDA detector.…”

Waveform Optimization for the In Vitro Detection of Caffeic Acid by Fast-Scan Cyclic Voltammetry

“…Because of its importance, various instrumental methods are available for detecting caffeic acid including ultraviolet–visible (UV–vis), fluorescence, and Raman spectroscopies, chromatography, and electrophoresis. − The presence of the catechol moiety within caffeic acid makes it electrochemically active, capable of undergoing a two electron, two proton reduction into caffeic acid o-quinone as shown in Scheme . Indeed, there have been several publications in recent years demonstrating cyclic, square wave, and differential pulse voltammetric approaches capable of measuring caffeic acid, with a focus on chemically modified and nanodecorated macroelectrodes. ,− Several recent works have also published comparisons of analytical figures of merit across these various approaches, highlighting nM detection limits or lower available for caffeic acid detection. ,,,− …”