Chemical warfare agents (CWAs) are unarguably one of the most feared toxic substances produced by mankind. Their inception in conventional warfare can be traced as far back as the Middle Ages but their full breakthrough as central players in bellic conflicts was not realized until World War I. Since then, more modern CWAs along with efficient methods for their manufacture have emerged and violently shaped the way modern warfare and diplomatic relations are conducted. Owing to their mass destruction ability, counter methods to mitigate their impact appeared almost immediately on par with their development. These efforts have focused on their efficient destruction, development of medical countermeasures and their detection by modern analytical chemistry methods. The following review seeks to provide the reader with a broad introduction on their direct detection by gas chromatography-mass spectrometry (GC-MS) and the various sample derivatization methods available for the analysis of their degradation products. The review concentrates on three of the main CWA classes and includes the nerve agents, the blistering agents and lastly, the incapacitating agents. Each section begins with a brief introduction of the CWA along with discussions of reports dealing with their detection in the intact form by GC-MS. Furthermore, as products arising from their degradation carry as much importance as the agents themselves in the field of forensic analysis, the available derivatization methods of these species are presented for each CWA highlighting some examples from our lab in the Forensic Science Center at the Lawrence Livermore National Laboratory.
Knowledge about the mechanisms involved in the structural development of solid materials at the atomic level is essential for designing rational synthesis protocols for these compounds, which may be used to improve desired technical properties, such as light emission, conductivity, magnetism, porosity or particle size, and may allow the tailored design of solid materials to generate the aforementioned properties. Recent technological advancements have allowed the combination of synchrotron-based in situ X-ray diffraction (XRD) with in situ optical spectroscopy techniques, providing researchers with remarkable opportunities to directly investigate structural changes during synthesis reactions. Among the various available methods to measure optical properties, in situ luminescence, UV/Vis absorption, and light transmission spectroscopies are highlighted here, with in situ luminescence being subdivided into in situ luminescence analysis of coordination sensors (ILACS) and time-resolved laser fluorescence spectroscopy (TRLFS). This article consists of a review of 122 references exploring various aspects of in situ analyses, with particular emphasis on the use of XRD-combined techniques in the study of metal-ligand exchange processes during the formation, phase transitions and decomposition of solid materials, including complexes, coordination polymers, metal-organic frameworks, nanoparticles and polyoxo- or chalcogenide metallates. We will then conclude with an exploration of future trends in this exciting research field.
A better elucidation of molecular mechanisms underlying drug-membrane interaction is of great importance for drug research and development. To date, different biochemical and biophysical methods have been developed to study biological membranes at molecular level. This review focuses on the recent applications and achievements of modern analytical techniques in the study of drug interactions with lipid membranes, including chromatography, spectrometry, calorimetry, and acoustic sensing. The merits and limitations of these techniques were compared and critically discussed. Moreover, various types of biomimetic model membranes including liposomes, lipid monolayers, and supported lipid monolayers/bilayers were described. General mechanisms underlying drug-membrane interaction process were also briefly introduced.
