Solid Phase Mesh Enhanced Sorption from Headspace (SPMESH) Coupled to DART-MS for Rapid Quantification of Trace-Level Volatiles

Abstract

Quantitation of trace-level (μg/L to ng/L) volatile compounds is routinely performed in a broad range of applications, including analyses of odorants, pesticide residues, or toxins in foodstuffs and related matrices. Conventional analyses based on gas chromatography-mass spectrometry (GC-MS) are limited by low throughput, and ambient approaches to sample introduction have typically had poor sensitivity. We prepared polydimethylsiloxane-coated stainless steel meshes for extraction and preconcentration of volatiles (Solid Phase Mesh Enhanced Sorption from Headspace, SPMESH), which could then be analyzed by Direct Analysis in Real Time (DART)-MS. The SPMESH cards were characterized by electron microscopy, and figures of merit for the approach were determined using two representative volatiles: 2-isobutyl-3-methoxypyrazine (IBMP) and linalool. Using DART-MS/MS and isotopically labeled internal standards, we achieved detection limits of 21 ng/L and 71 μg/L for IBMP and linalool in water. Good accuracy and precision could also be achieved for IBMP spikes in grape macerate, although accuracy for linalool was compromised by the presence of interferences. Detection limits could be further improved by an order of magnitude through the use of high resolution (HR) MS. Because extraction can be performed inexpensively in parallel and because it requires short data acquisition times (<1 min), SPMESH-DART-MS may be appropriate for high throughput trace level volatile analyses.

High‐throughput quantification of drugs of abuse in biofluids via 96‐solid‐phase microextraction–transmission mode and direct analysis in real time mass spectrometry

“…AIMS techniques are generally regarded as methods that offer limited quantitative abilities, but over the last few years there has been a rise in publications reporting otherwise, particularly for DART applications . As mentioned in the introduction, and as shown by Pérez et al sample‐preparation devices that have been normalized (i.e.…”

“…TM device with a defined geometry and coated area) are one of the crucial components for guaranteeing reproducible quantitative results. Several articles published by the groups of Pawliszyn and Sacks have documented how coupling SPME‐TM to DART‐MS can provide analysts with reasonable quantitative results.…”

Development, Optimization and Applications of Thin Film Solid Phase Microextraction (TF-SPME) Devices for Thermal Desorption: A Comprehensive Review

“…It should be noted that alternative forms of TD for TF-SPME devices have been recently reported. These methods use "transmission mode" devices consisting of a coated mesh-like surface to enrich analytes and subsequently both desorb and ionize in one step using ambient ionization methods [37][38][39]. Direct analysis in real time (DART), an ambient ion source that has been shown to be well suited for onsite analysis [40], can be simply coupled to TF-SPME (coated mesh-like geometry) by positioning the device in-between the ion source and the mass spectrometer (MS).…”

“…Direct analysis in real time (DART), an ambient ion source that has been shown to be well suited for onsite analysis [40], can be simply coupled to TF-SPME (coated mesh-like geometry) by positioning the device in-between the ion source and the mass spectrometer (MS). In this way, a stream of heated plasma (most often helium) desorbs the TF-S4PME transmission device while also ionizing analytes at the same time [37,38]. Another ambient ionization source, dielectric barrier discharge ionization (DBDI), has also been proven to be well suited for the analysis of illicit drugs using TF-SPME devices [39].…”

“…These studies [34,66] compared the performance of TF-SPME to fiber SPME with the same stationary phase, revealing enhanced extraction efficiency and capacity for the TF-SPME devices. In 2016, another study investigated the fragrance of various essential volatile compounds from grapes, including linalool and 3-isobutyl-2-methoxypyrazine (IBMP), which were measured using PDMS-based TF-SPME devices [38]. This novel solid-phase mesh-enhanced sorption from headspace (SPMESH) method developed by Jastrzembski and colleagues resulted in greater throughput and enhanced limits of quantitation (ppb) during the analysis of volatile compounds (such as odorants) compared to other traditional methods.…”