Opportunities in phytochemistry, ecophysiology and wood research via laser ablation direct analysis in real time imaging-mass spectrometry.

Analysis of wood transects in a manner that preserves the spatial distribution of the metabolites present is highly desirable to among other things: (1) facilitate ecophysiology studies that reveal the association between chemical make-up and environmental factors or climatic events over time; and (2) investigate the mechanisms of the synthesis and trafficking of small molecules within specialised tissues. While a variety of techniques could be applied to achieve these goals, most remain challenging and impractical. Laser ablation direct analysis in real time imaging-mass spectrometry (LADI-MS) was successfully used to survey the chemical profile of wood, while also preserving the small-molecule spatial distributions.

A validated method for the quantification of mitragynine in sixteen commercially available Kratom (Mitragyna speciosa) products.

The recent rise in the recreational use of plant-based "legal highs" has prompted the development of methods for the identification of the bulk material, and quantification of their psychoactive components. One of these plants is Mitragyna speciosa, commonly referred to as Kratom. While traditional use of this plant was primarily for medicinal purposes, there has been a rise in its recreational use, and as a self-prescribed medication for opioid withdrawal.

Spatial distributions of furan and 5-hydroxymethylfurfural in unroasted and roasted Coffea arabica beans.

For the first time, the spatial distributions of the highly volatile compounds furan and 5-hydroxymethylfurfural (HMF) have been determined in cross sections of green and roasted Coffea arabica beans. The image maps were revealed by laser ablation DART imaging mass spectrometry (LADI-MS). The presence of these compounds was independently confirmed by GC-MS as well as argon DART-MS.

Utilizing Direct Analysis in Real Time-High Resolution Mass Spectrometry-Derived Dark Matter Spectra to Classify and Identify Unknown Synthetic Cathinones.

Herein we describe a new method of statistical analysis processing of direct analysis in real time-high resolution mass spectrometry-derived neutral loss spectra of synthetic cathinones. The dark matter observed under collision-induced dissociation conditions is rendered as "neutral loss spectra," and these are subsequently subjected to statistical analysis processing, specifically hierarchical clustering analysis. The resulting hierarchical clustering dendrogram provides a means by which to classify an unknown as a member of a subgroup of cathinones, based on structural similarity of its backbone to that of the scaffolds of the drugs represented in the training set.

A Rapid, High-Throughput Validated Method for the Quantification of Atropine in Datura stramonium Seeds Using Direct Analysis in Real Time-High Resolution Mass Spectrometry (DART-HRMS).

The utility of direct analysis in real time-high resolution mass spectrometry (DART-HRMS) for quantification of a variety of compounds has been explored, but the number of reports of validated methods using this technique is limited. Furthermore, despite the increasing use in crime labs of DART-HRMS for the detection and identification of drugs of abuse, very few published reports have appeared describing how the method can be exploited for the analysis of small molecules of interest within complex matrices such as plant tissues. Herein we describe the steps to be taken to establish a validated quantification method for psychoactive compounds within complex plant matrices through its application to the detection and quantification of atropine in Datura stramonium seeds.

Identification and classification of cathinone unknowns by statistical analysis processing of direct analysis in real time-high resolution mass spectrometry-derived "neutral loss" spectra.

An approach to the rapid determination of the structures of novel synthetic cathinone designer drugs, also known as bath salts, is reported. While cathinones fragment so extensively by electron impact mass spectrometry that their mass spectra often cannot be used to identify the structure, collision-induced dissociation (CID) direct analysis in real time-high resolution mass spectrometry (DART-HRMS) experiments furnished spectra that provided diagnostic fragmentation patterns for the analyzed cathinones. From this data, neutral loss spectra, which reflect the presence of specific chemical moieties, could be acquired.

Development of "Laser Ablation Direct Analysis in Real Time Imaging" Mass Spectrometry: Application to Spatial Distribution Mapping of Metabolites Along the Biosynthetic Cascade Leading to Synthesis of Atropine and Scopolamine in Plant Tissue.

Methods for the accomplishment of small-molecule imaging by mass spectrometry are challenged by the need for sample pretreatment steps, such as cryo-sectioning, dehydration, chemical fixation, or application of a matrix or solvent, that must be performed to obtain interpretable spatial distribution data. Furthermore, these steps along with requirements of the mass analyzer such as high vacuum, can severely limit the range of sample types that can be analyzed by this powerful method. Here, we report the development of a laser ablation-direct analysis in real time imaging mass spectrometry approach which couples a 213 nm Nd:YAG solid state UV laser to a direct analysis in a real time ion source and high-resolution time-of-flight mass spectrometer.

Mechanosensitivity below Ground: Touch-Sensitive Smell-Producing Roots in the Shy Plant Mimosa pudica.

The roots of the shy plant Mimosa pudica emit a cocktail of small organic and inorganic sulfur compounds and reactive intermediates into the environment, including SO2, methanesulfinic acid, pyruvic acid, lactic acid, ethanesulfinic acid, propanesulfenic acid, 2-aminothiophenol, S-propyl propane 1-thiosulfinate, phenothiazine, and thioformaldehyde, an elusive and highly unstable compound that, to our knowledge, has never before been reported to be emitted by a plant. When soil around the roots is dislodged or when seedling roots are touched, an odor is detected. The perceived odor corresponds to the emission of higher amounts of propanesulfenic acid, 2-aminothiophenol, S-propyl propane 1-thiosulfinate, and phenothiazine.