Advances in chemistry applied to forensic science

Acts of terrorism, an increase in the use of firearms, drug abuse, the use of so-called date-rape drugs, and driving whilst under the influence of drugs, are just some of the subjects frequently in the news. In the absence of fingermarks and of material leading to the recovery of DNA, the forensic scientist has to rely upon chemical analysis of trace amounts of materials including explosives, drugs, toxicological specimens, firearms discharge residues, fibres, glass, paint, soil etc., in order to establish or eliminate links between suspect and victim and/or scene. This tutorial review describes analytical problems facing the forensic chemist, and the current methods and techniques employed to tackle them.     

聚离子液体材料在分离科学中的研究进展

离子液体作为新型离子化试剂,具有诸多优越的物理化学性质,比如:良好的溶解性、导电性、热稳定性、生物相容性及低蒸气压和不易燃等特点,近年来在分析化学领域得到广泛关注。聚离子液体材料结合了离子液体和聚合物的双重性质,已经成为分离科学研究的前沿领域。本文详细讨论了离子液体与目标物之间的多种作用机制,比如亲/疏水作用、氢键作用、离子交换、π - π 堆积及静电吸附作用等等,总结了聚离子液体材料在固相萃取、液相色谱、气相色谱、毛细管电泳及毛细管电色谱等领域的研究进展;最后,对聚离子液体材料的发展前景进行了展望。     

Advances in capillary electrochromatography and micro-high performance liquid chromatography monolithic columns for separation science

Over the last decade, monoliths or continuous beds have emerged as an alternative to traditional packed-bed columns for use in capillary electrochromatography (CEC) and micro-high performance liquid chromatography (micro-HPLC). Monolithic columns can be divided into two categories: silica-based monolithic columns and rigid organic polymer-based monolithic columns resulting from the polymerization of acrylamide, styrene, acrylate or methacrylate monomers. In this paper, the chemistry and most recent applications of these various types of monoliths in both CEC and micro-HPLC are presented.     

Advances in mass spectrometry applied to pharmaceutical metabolomics

Metabolomics, also referred to in the literature as metabonomics, is a relatively new systems biology tool for drug discovery and development and is increasingly being used to obtain a detailed picture of a drug’s effect on the body. Metabolomics is the qualitative assessment and relative or absolute quantitative measurement of the endogenous metabolome, defined as the complement of all native small molecules (metabolites less than 1,500 Da). A metabolomics study frequently involves the comparative analysis of sample sets from a normal state and a perturbed state, where the perturbation can be of any nature, such as genetic knockout, administration of a drug, or change in diet or lifestyle. Advances in mass spectrometry (MS) technologies including direct introduction or in-line chromatographic separation modes, ionization techniques, mass analyzers, and detection methods have provided powerful tools to assess the molecular changes in the metabolome. This review focuses on advances in MS pertaining to the analytical data generation for the main metabolomics methods, namely, fingerprinting, nontargeted, and targeted approaches, as they are applied to pharmaceutical drug discovery and development.     

Mass selective separation applied to radioisotopes of cesium

A technique that uses the intrinsic mass‐based separation capability of a quadrupole mass spectrometer has been used to resolve spectral radiometric interference of two isotopes of the same element. In this work the starting sample was a mixture of ¹³⁷Cs and ¹³⁴Cs and was (activity) dominated by ¹³⁷Cs. This methodology separated and ‘implanted’ ¹³⁴Cs that was later quantified for spectral features and activity with traditional radiometric techniques. This work demonstrated a ¹³⁴Cs/¹³⁷Cs activity ratio enhancement of >4 orders of magnitude and complete removal of ¹³⁷Cs spectral features from the implanted target mass (i.e. 134). Copyright © 2016 John Wiley & Sons, Ltd.     

Monolithic systems: from separation science to heterogeneous catalysis

Recent results that have been obtained in the ring-opening metathesis polymerization (ROMP)-based synthesis of monolithic supports are summarized. We have elaborated a synthetic concept that allows modifying monolithic supports in a way that they can be used both for applications in separation science, for SEC and as supports for catalytically active systems. In all cases, a tailor-made microstructure was accessible due to the controlled character of the transition-metal catalyzed polymerization. Taking advantage of the “living” catalytic sites, an “in situ” functionalization was accomplished by subsequently grafting a variety of functional monomers and catalyst precursors onto the rod. Their design and use as supports for high-performance separation devices (e.g. for ds-DNA) and catalytic supports (e.g. supported Grubbs-type catalysts) is summarized.     

Calorimetric methods applied to the investigation of divided systems in colloid science

A new batch titration microcalorimeter has been used for estimation of thermodynamic properties in various investigated colloidal systems. As examples, we present enthalpic and kinetic data obtained from this calorimetric device for four different processes widely encountered in colloid science:

Traditional Chinese medicine and separation science

Traditional Chinese medicines (TCMs) are getting more and more popular nowadays in the whole world for improving health condition of human beings as well as preventing and healing diseases. TCM is a multi-component system with components mostly unknown, and only a few compounds are responsible for the pharmaceutical and/or toxic effects. The large numbers of other components in the TCM make the screening and analysis of the bioactive components extremely difficult. So, separation and analysis of the desired chemical components in TCM are very important subjects for modernization research of TCM. Thus, many novel separation techniques with significant advantages over conventional methods were introduced and applied to separation and analysis of the chemical constituents in TCM. This review presents just a brief outline of the applications of different separation methods for the isolation and analysis of TCM constituents.     

木质纤维素类生物质组分分离研究进展

木质纤维素类材料在地球上大量存在,来源广泛. 对木质纤维素废料进行处理,可以废物回收,避免环境问题. 由于木质纤维素材料细胞壁较厚,细胞壁中含结晶结构,进行透射电子显微镜观察前需经过前处理. 对木质纤维素材料的样品前处理方法进行了详细说明,包括取材、固定、洗涤、脱水、包埋和渗透、切片及染色,可为其制备提供参考.     

基于微流控芯片的细胞外囊泡分离技术研究进展

细胞外囊泡（extracellular vesicles，EVs）是脂质双分子层包绕形成的半球状囊泡。研究表明EVs存在重要的生物学功能，同时EVs排放的数量、种类以及内含蛋白质、脂质或RNA等构成变化与疾病密切相关。EVs的研究将有助于理解其生物学功能和作用机制，同时也有望用于疾病的诊断和治疗，因此拥有巨大的临床应用前景。从复杂的体液样品中分离捕获EVs是实现基于EVs开展医学研究以及临床诊断的前提，但是目前绝大多数的EVs分离捕获仍然是采用传统分离手段，纯度低、效率差，迫切需要高效和高选择性的EVs分离手段。先进的微流控芯片技术具有微型化、集成化和自动化的优势，利用微流控芯片的EVs分离技术研究已成热点，本文围绕相关研究的最新进展进行了综述。     

树状大分子接枝型聚合物色谱分离材料研究进展

随着色谱固定相制备技术和材料科学领域的不断发展,目前已经有大量修饰方法和新型材料被用于固相萃取、高效液相色谱以及离子色谱聚合物固定相填料的功能化修饰。其中聚酰胺-胺(PAMAM)树状大分子由于其独特的结构和性质,在色谱分离材料结构完善和性能提升中也发挥了重要的作用。该文主要综述了PAMAM树状大分子在以聚合物为基质的色谱分离材料修饰中的应用,并对其今后的发展进行了展望。     

Inorganic monoliths in separation science: A review

The practical application of rigid, macro-porous organic polymer and silica based monolithic stationary phases as separation media has been described in the literature since 1992 and 1996, respectively. Today these materials are extensively used in chromatography and electrochromatography and several detailed reviews appear annually describing these materials, their synthesis and application. To compliment these publications, this review focuses upon the less commonly utilised materials for monolith synthesis, both those that have already been applied within separation science, and those that have found applications elsewhere, such as catalysis and water filtration, but have the clear potential to be explored as novel stationary phases in the near future. For the purpose of the review monoliths formed from these various alternative materials will be termed ‘Exotic Monoliths’, as these new substrates in many cases have only just begun to be explored for chromatographic separations, and in many instances have unusual and highly selective surface chemistries, which are attractive in terms of broadening the choice of monolithic materials for separation science. An extensive range of monolithic materials based on the following elements and their compounds (mostly oxides) are covered: Zr, Ti, Al, Hf, C, Au, Ag, Ce, Ge and hydroxyapatite, together with their relevant properties, methods of synthesis, and current and potential applications in separation science.