Publications

Sprayed liquid-gas extraction of semi-volatile organophosphate Malathion from air and contaminated surfaces

Abstract

In this study, a new air sampling method termed sprayed liquid–gas extraction (SLGE) was developed for semi-volatile organic compounds. Water droplets with an average diameter of less than 10 μm were created, using a flow blurring nebulizer from distilled water and the gas-phase sample. This allowed the fast, simple and highly-efficient enrichment of trace levels of the widely used organophosphate insecticide malathion, which is also an accepted simulant for the potent nerve-agent VX.

Sprayed liquid-gas extraction in combination with ion mobility spectrometry: a novel approach for the fast determination of semi-volatile compounds in air and from contaminated surfaces

Abstract
We developed a fast, simple and highly-efficient enrichment procedure for trace levels of semi volatile organic compounds from air and surfaces and combined it with ion mobility spectrometry as field-deployable and rapid analytical technique. Our new technique, the sprayed liquid-gas extraction, was developed and optimized to allow the enrichment of semi volatile organic compounds. The air sample is pumped through a flow blurring nebulizer together with water. The sprayed liquid is collected and the organic compounds are transferred from the water phase to n-hexane via a miniscale liquid-liquid extraction. 50 μL of the n-hexane extract is applied to a fiber tape. After the n-hexane has evaporated, the fiber tape is transferred to the thermodesorber unit of a GDA-X ion mobility spectrometer (Airsense, Schwerin, Germany). The whole sampling and the sample preparation procedure takes no longer than 15 min and only requires 2.5 mL organic solvent. The method was optimized for Malathion, a widely used organophosphate insecticide and an accepted simulant for the nerve-agent, VX. Malathion provides defined ion mobility spectra in both, the positive and negative mode. The positive spectra show one major peak with a reduced mobility of 1.197 cm2 Vs−1 and an additional peak at 1.449 cm2 Vs−1 with lower intensity. A major product ion peak of 1.720 cm2 Vs−1 can be detected in negative mode together with an additional peak of low intensity at 1.403 cm2 Vs−1. The detection limit of the ion mobility spectrometer is approximately 20 ng absolute.

Robotic and autonomous countermeasures

Security and defence discussions are now filled with speculation about robot weapons and artificial intelligence (AI). The problem is, security cannot be built on robotic weapons, autonomous systems or AI alone. Autonomous systems are more like operating platforms and firing systems than weapons per se. For example, electro-optical weapons, firearms, missiles, and nuclear weapons are defined by their impact. Robotised features simply increase that impact.

To continue reading please click on the link below.

Inter-laboratory exercise with an aim to compare methods for 90Sr and 239,240Pu determination in environmental soil samples

Abstract
In order to deliver reliable results for a multitude of different scenarios, e.g. emergency preparedness, environmental monitoring, nuclear decommissioning and waste management, there is a constant process of method development in the field of radioanalytical chemistry. This work presents the results of a method comparison exercise aimed at quantifying 90Sr and 239,240Pu in environmental soil samples, with the intention of evaluating the performance and applicability of different methods. From the methods examined in this work, recommendations are given in order to find a radioanalytical measurement procedure, for 90Sr and 239,240Pu analysis, which is fit-forpurpose for a particular scenario.

A rapid and non-invasive method to determine toxic levels of alcohols and γ-hydroxybutyric acid in saliva samples by gas chromatography-differential mobility spectrometry

Work over the first eighteen months of the project has identified metabolomic markers of exposure to pesticides and toxic alcohols. A publication by Prof Thomas's Loughborough group reported identification of the toxic alcohols methanol, ethylene glycol, and 1,3-propandiol, and their metabolites, as well as ethanol in human saliva.

Mental health surveillance after the terrorist attacks in Paris

The terror events in Paris in November, 2015, and elsewhere remind us of the substantial consequences that violent events can have for a population's mental health. Although effective approaches exist for treating these consequences, no systematic attempts have been made to identify populations at risk early on to expeditiously mitigate them. Social media could help identify populations in need during and after disasters.