Determination and characterization of organic explosives using porous graphitic carbon and liquid chromatography-atmospheric pressure chemical ionization mass spectrometry.

This review covers the latest developments and applications of nano-materials in stationary phase development for various modes of high-performance liquid chromatography. Specific attention is placed upon the development of new composite phases, including the synthetic and immobilisation strategies used, to produce either encapsulated nano-particles, or surface attached nano-particles, layers, coatings and other structures. The resultant chromatographic applications, where applicable, are discussed with comment upon enhanced selectivity and/or efficiency of the nano-particle modified phases, where such effects have been identified. In the main this review covers developments over the past five years and is structured according to the nature of the nano-particles themselves, including carbonaceous, metallic, inorganic, and organopolymer based materials.

Nano-particle modified stationary phases for high-performance liquid chromatography

A fast liquid chromatography quadrupole time-of-flight mass spectrometry (LC-QToF-MS) method for the identification of organic explosives and propellants

Carbonaceous nanomaterials (CNMs) are prevalent in many disciplines In separation science, CNMs have made great contributions to the innovation of stationary phases for various chromatographic technologies In this review article, we present an up-to-date overview of the development of stationary phases based on CNMs for high-performance liquid chromatography (HPLC) We devote a large part of this review to the accomplishments in the past five years with regard to retention and selectivity offered by new HPLC stationary phases modified with different types of CNMs, mainly including carbon nanotubes, fullerenes, nanographene and nanodiamonds We pay specific attention to the approaches to chemical immobilization involving different types of CNM in synthesizing stationary phases

Progress in stationary phases modified with carbonaceous nanomaterials for high-performance liquid chromatography

A new method has been developed to facilitate the use of fullerenes as stationary phases (SPs) in gas chromatography (GC). In this method, ionic liquids (ILs) are used as solvents to coat fullerenes (C60, amino-C60 and hydroxy-C60) onto GC columns. However, the ILs serve not just as coating solvents but also act synergistically with fullerenes to provide unique properties as stationary phases, namely dual modal characteristics. They act as non-polar SPs when separating non-polar analytes (aromatic hydrocarbon mixtures and alkane mixtures), and as polar SPs for polar analytes (e.g., alcohol mixtures). The polarity of the stationary phase can be adjusted by changing either the type of the IL and/or by adding either C60 (or its amino or hydroxy derivatives) to the IL. It was found that C60 and its derivatives produce not only a change in the polarity of the SP but also substantial enhancement in separation efficiencies for both non-polar and polar analytes. More importantly, when added to the IL SP, C60 improves separation efficiencies not just for non-polar analytes (aromatic hydrocarbon mixtures and alkane mixtures) but also for polar analytes (mixtures of ortho-, meta- and para-xylene and alcohol mixtures) as well. Moreover, C60SP provides higher efficiencies than amino-C60 and hydroxy-C60 for separation of polar analytes. This is rather surprising considering that not only are amino-C60 and hydroxy-C60 more polar than C60, but that the IL used to coat the amino- and hydroxy-C60 (i.e., N-ethylpyridinium trifluoroacetate, [EtPy+ CF3COO−]) is more polar than the IL used to coat the C60 (i.e., octylmethylimidazolium bis(trifluoromethyl)sulfonyl)amide], [OMIm+ (CF3SO2)2N−]). Moreover, compared to its amino and hydroxy derivatives, the concentration of C60 in the column was 10 times lower.

Fullerene-impregnated ionic liquid stationary phases for gas chromatography

Stationary Phases 45(1). Chromatographic Separation of High Energetic Materials with C60‐Fullerene Stationary Phase

On decrit une methode d'analyse en phase liquide a haute pression (HPLC) pour le RDX et le HMX avec une nouvelle phase stationnaire, le copoly(vinylthiazole-vinylimidazole). Les temps d'elution pour le RDX et le HMX avec cette phase stationnaire en utilisant du methanol/ eau (proportion 60/40 a 90/10) en tant que phase mobile donnent HMX > RDX, ce qui est tres different d'une phase RP-18 de type commercial. La selectivite chromatographique (valeurs α) entre RDX et HMX est de l'ordre de 2,40 a 2,55. Cet avantage peut etre utilise, lors de la synthese de HMX p. ex., pour detecter la presence de petites impuretes d'env. 1 ppm de RDX dans le HMX.

Cheng-Hau Wen

Papers

Stationary Phases 45(1). Chromatographic Separation of High Energetic Materials with C60‐Fullerene Stationary Phase

Stationary phases. Part 39(1): Trace analysis of RDX in HMX on a novel copoly(vinylthiazole‐vinylimidazole) stationary phase by HPLC