Chemical Fingerprinting of Olive Oils by Electrospray Ionization-Differential Mobility Analysis-Mass Spectrometry: A New Alternative to Food Authenticity Testing.

Recently, the olive oil industry has been the subject of harsh criticism for false labeling and even adulterating olive oils. This situation in which both the industry and the population are affected leads to an urgent need to increase controls to avoid fraudulent activities around this precious product. The aim of this work is to propose a new analytical platform by coupling electrospray ionization (ESI), differential mobility analysis (DMA), and mass spectrometry (MS) for the analysis of olive oils based on the information obtained from the chemical fingerprint (nontargeted analyses).

Tandem Ion Mobility Spectrometry for the Detection of Traces of Explosives in Cargo at Concentrations of Parts Per Quadrillion.

A tandem ion mobility spectrometer (IMS) built from two differential mobility analyzers (DMAs) is coupled at ambient pressure with a thermal fragmenter placed in between, such that the precursor ions selected in the first DMA are thermally decomposed at ambient pressure in the fragmenter and the product ions generated are filtered in the second DMA. A thermal desorber and a multicapillary gas chromatography (GC) column are coupled to a secondary electrospray (SESI) ion source, so the adsorption sampling filters are thermally desorbed and the liberated vapors are separated in the GC column, prior to their ionization and mobility/mobility classification. The new fragmenter allows the fragmentation of the five explosives studied: RDX, PETN, NG, EGDN, and TNT.

Rapid detection of explosive vapors by thermal desorption atmospheric pressure photoionization differential mobility analysis tandem mass spectrometry.

Rationale: The increased frequency in the number of international terror threats has led to a corresponding increase in demand for fast, sensitive and reliable screening methods suitable for the detection of airborne explosive vapors. We demonstrate herein a workflow suitable for the determination of nitrogen-based explosives at the picogram level in just minutes.

Methods: A method is described that combines Thermal Desorption (TD) sample introduction with Differential Mobility Analysis (DMA) Tandem Mass Spectrometry (MS/MS), enabling a sensitive and accurate workflow suitable for the rapid detection of trace nitroaromatic, nitroester and nitramine explosive vapors.

Planar Differential Mobility Analyzer with a Resolving Power of 110.

Planar differential mobility analyzers (DMAs) have previously achieved resolving powers of 60-80 in air or N at the mobility of the tetraheptylammonium ion (THA, ∼0.97 cm/V/s). For unclear reasons, this performance is considerably below the theoretical limit.

Ion Mobility Spectrometer-Fragmenter-Ion Mobility Spectrometer Analogue of a Triple Quadrupole for High-Resolution Ion Analysis at Atmospheric Pressure.

Two differential mobility analyzers (DMAs) acting as narrow band mobility filters are coupled in series, with a thermal fragmentation cell placed in between, such that parent ions selected in DMA are fragmented in the cell at atmospheric pressure, and their product ions are analyzed on DMA. Additional mass spectrometer analysis is performed for ion identification purposes. A key feature of the tandem DMA is the short residence time (∼0.

Mobility Peak Tailing Reduction in a Differential Mobility Analyzer (DMA) Coupled with a Mass Spectrometer and Several Ionization Sources.

The differential mobility analyzer (DMA) is a narrow-band linear ion mobility filter operating at atmospheric pressure. It combines in series with a quadrupole mass spectrometer (Q-MS) for mobility/mass analysis, greatly reducing chemical noise in selected ion monitoring. However, the large flow rate of drift gas (~1000 L/min) required by DMAs complicates the achievement of high gas purity.