Recent advances in capillary separations for proteomics

The sequencing of several organisms' genomes, including the human's one, has opened the way for the so-called postgenomic era, which is now routinely coined as "proteomics". The most basic task in proteomics remains the detection and identification of proteins from a biological sample, and the most traditional way to achieve this goal consists of protein separations performed by two-dimensional polyacrylamide gel electrophoresis (2-D PAGE). Still, the 2-D PAGE-mass spectrometry (MS) approach remains lacking in proteome coverage (for proteins having extreme isoelectric points or molecular masses as well as for membrane proteins), dynamic range, sensitivity, and throughput. Consequently, considerable efforts have been devoted to the development of non-gel-based proteome separation technologies in an effort to alleviate the shortcomings in 2-D PAGE while reserving the ability to resolve complex protein and peptide mixtures prior to MS analysis. This review focuses on the most recent advances in capillary-based separation techniques, including capillary liquid chromatography, capillary electrophoresis, and capillary electrokinetic chromatography, and combinations of multiples of these mechanisms, along with the coupling of these techniques to MS. Developments in capillary separations capable of providing extremely high resolving power and selective analyte enrichment are particularly highlighted for their roles within the broader context of a state-of-the-art integrated proteome effort. Miniaturized and integrated multidimensional peptide/protein separations using microfluidics are further summarized for their potential applications in high-throughput protein profiling toward biomarker discovery and clinical diagnosis.     

核酸适配体亲和色谱的研究进展

核酸适配体亲和色谱是将核酸适配体作为色谱固定相上的亲和配体的一种新型色谱技术。核酸适配体是一种可以特异性地识别目标物的寡聚核苷酸,与免疫抗体相比,核酸适配体在筛选制备、稳定性及应用等方面都显示出独特的优点。本文介绍了核酸适配体亲和色谱在小分子、蛋白质和细胞的分离和分析中的应用,对核酸适配体亲和色谱的研究现状和发展前景进行了综述。     

Recent advances in affinity capillary electrophoresis

Use of the specificity of (bio)interactions can effectively overcome the selectivity limitation faced in capillary electrophoresis (CE), and the resulting technique usually is referred to as affinity capillary electrophoresis (ACE). Despite the high selectivity of ACE, several important problems still need to be addressed. A major issue in all CE separations, including ACE, is the concentration detection limit. Using UV detection, this is usually in the order of 10(-6) M whereas laser-induced fluorescence (LIF) detection can provide detection limits down to the sub-10(-10) M range. However, a marked disadvantage of LIF is that labeling of the analytes is usually required, which might change the interaction behavior of the solutes under investigation. Additionally, labeling reactions at sub-10(-10) M concentration levels are certainly not trivial and often difficult to perform quantitatively. Alternative and universal detection approaches, particularly mass spectrometric (MS) detection, look very promising but (A) CE-MS techniques are still far from routine application. Important future progress in sensitive detection strategies is likely to increase the use of ACE in the future.     

Recent advances in the formation of ultrathin polymeric membranes for gas separations

During the past 20 years membrane systems have been applied to a limited number of commercial gas separations. To further advance membrane-based gas separations, current research efforts focus on optimization of (i) membrane materials, (ii) membrane structures and (iii) membrane system design. In this overview, recent developments in the formation of high-performance gas separation membranes are discussed. The gas separation properties of state-of-the-art integrally skinned asymmetric membranes and thin-film composite membranes are summarized. Future directions for the preparation of advanced gas separation membranes are highlighted.     

Recent advances in new-type molecular switches

Molecular switches that can undergo reversible switching between two or more different states in response to external stimuli have been used in the fabrication of various optoelectronic devices and smart materials for many decades, and also found many applications in sensing, molecular self-assembly and photo-controlled biological systems. Recently, mechanically interlocked molecules, such as rotaxanes and catenanes, and molecular rotary motors based on overcrowded alkenes have emerged as two new kinds of molecular switches. Some novel applications of above-mentioned molecular switches have been discovered. In this mini review, we mainly highlight noticeable achievements over the past decade in this field, and summarize the applications of new types of molecular switches, for instance, controlling the chiral space to regulate catalytic reaction as organocatalysts, controlling molecular motions, synthesizing a peptide in a sequence-specific manner and modulating the wettability of the self-assembled monolayers.     

Recent advances in peptide and peptidomimetic stereoisomer separations by capillary electromigration techniques

As the stereochemistry of peptides determines their physicochemical properties and biological activities, analytical methods able to discriminate between peptide stereoisomers are important especially with regard to pharmaceutical peptides and peptidomimetics. The present review summarizes recent developments in peptide and peptidomimetic stereoisomer separations by capillary electromigration techniques. The majority of separations were performed by CE while only few reports have been published on the subject of electrochromatography. In addition to systematic studies on the applicability of certain buffer additives and the evaluation of specific experimental conditions, there have been attempts to understand the mechanistic aspects of peptide stereoisomer separations as well as to analyze the structure of peptide-CD complexes.     

Recent advances in photofunctional polymorphs of molecular materials

Crystalline polymorph is an intriguing phenomenon that the presence of multiple packing and aggregate architectures of the same molecular system.In this review,we focus on the recent progress in various feasible methods of molecule-based crystalline polymorphism growth,their adjustable photofunctional properties and multifunctional applications,which will help to illustrate the structure-property relationship.     

Recent advances in photofunctional polymorphs of molecular materials

Recently, molecule-based luminescent materials have been drawing extensive attention due to their desirable properties and promising applications in the fields of sensors, lighting display, and cell imaging. Crystalline polymorph is an intriguing phenomenon that the presence of multiple packing and aggregate architectures of the same molecular system. The studies on polymorphs for molecule-based fluorophores provide the opportunities to adjust the mode of molecular packing and photophysical properties, which will help to illustrate the structure-property relationship. In this review, we focus on the recent progress in various feasible methods of molecule-based crystalline polymorphism growth and their adjustable photofunctional properties, which will open up possibilities of variant optical applications. Firstly, several effective ways to prepare and screen polymorphs are sorted out. And then, we discuss the discrepant properties and multifunctional applications (such as sensors, laser, and OFET, etc.). Finally, the development trends and future prospects of these polymorphs are also briefly introduced.     

Recent advances in molecular fluorescent probes for organic phosphate biomolecules recognition

Organic phosphate biomolecules (OPBs) are indispensable components of eukaryotes and prokaryotes, such as acting as the fundamental components of cell membranes and important substrates for nucleic acids. They play pivotal roles in various biological processes, such as energy conservation, metabolism, and signal modulation. Due to the difficulty of detection caused by variety OPBs, investigation of their respective physiological effects in organisms has been restrained by the lack of efficient tools. Many small fluorescent probes have been employed for selective detection and monitoring of OPBs in vitro or in vivo due to the advantages of tailored properties, biodegradability and in situ high temporal and spatial resolution imaging. In this review, we summarize the recent advances in fluorescent probes for OPBs, such as nucleotides, NAD(P)H, FAD/FMN and PS. Importantly, we describe their identification mechanisms in detail and discuss the general strategies for these OPBs probe designs, which provide new insights and ideas for the future probe designs.     

Recent advances in molecular fluorescent probes for organic phosphate biomolecules recognition

This review provided a systematic overview of the recent researches on the small-molecule fluorescent probes for recognition various organic phosphate biomolecules (OPBs) including nucleotides, NAD(P)H, FAD/FMN and PS. The general strategies and the recognition mechanisms for these OPBs probe designs were described and emphasized to inspire the better design for fluorescent probes in the future.     

Recent advances in spectroelectrochemistry related to molecular catalytic processes

Continuing interest in renewable energy utilization, the depletion of nonrenewable petrochemical feedstocks and rising atmospheric concentrations of CO₂ from anthropogenic emissions have made molecular electrocatalytic processes involving CO₂, H₂, and O₂ important research foci. One of the touted advantages of molecular electrocatalytic processes, in comparison to heterogeneous systems, is the relative ease with which the active species can be characterized and the catalyst optimized using synthetic methodology. This requires, however, that species generated by the application of potential be spectroscopically studied, which can be difficult given that changes in reactivity can occur. Spectroelectrochemical methods offer a way to study speciation as a function of potential and time, such that catalytic and noncatalytic reactivity can be understood in the context of an overall mechanism. Paired with steadily advancing electrochemical techniques for quantifying the thermodynamic and kinetic parameters of molecular electrocatalysts, spectroelectrochemical data sets can be used to generate a rich understanding of molecular behavior. Recent reports on the use of spectroelectrochemistry to understand molecular electrocatalytic reactions using transition metal complexes are summarized herein.     

Functional nanomachines: Recent advances in synthetic molecular machinery

A mini-review: As the top-down approach for miniaturisation of technology reaches its inherent limitations, robust strategies to build nanoscale machinery components, which have the ability to convert an input energy into motion, from the molecular level up, become increasingly important. Nature is certainly the most proficient in the control of molecular level motion; nevertheless, many successes have been enjoyed in the pursuit of mimicking key aspects of nature’s molecular machines, including two state switches, ion pumps, unidirectional rotary motors and molecular robots that can move molecular cargo. This mini-review outlines of some of the most impressive recent examples towards this end.     

Recent advances on quasi-solid-state electrolytes for supercapacitors

Solid-state and quasi-solid-state electrolytes have been attracting the scientific community’s attention in the last decade. These electrolytes provide significant advantages, such as the absence of leakage and separators for devices and safety for users. They also allow the assembly of stretchable and bendable supercapacitors. Comparing solid-state to quasi-solid-states, the last provides the most significant energy and power densities due to the better ionic conductivity. Our goal here is to p...     

Recent advances in the design of organic polymer monoliths for reversed-phase and hydrophilic interaction chromatography separations of small molecules

Owing to their favorable porous structure with pore size distribution shifted towards large flow-through pores, organic polymer monoliths have been mainly employed for the separation of macromolecules in gradient elution liquid chromatography. The absence of significant amounts of small pores with a stagnant mobile phase and the resulting low surface area were considered as the main reason for their poor behavior in the isocratic separation of small molecules. Several recent efforts have improved the separation power of organic polymer monoliths for small molecules offering column efficiency up to tens of thousands of plates per meter. These attempts include optimization of the composition of polymerization mixture, including the variation of functional monomer, the cross-linking monomer, and the porogen solvents mixture, adjustment of polymerization temperature, and time. Additionally, post-polymerization modifications including hypercross-linking and the use of carbon nanostructures showed significant improvement in the column properties. This review describes recent developments in the preparation of organic polymer monoliths suitable for the separation of small molecules in the isocratic mode as well as the main factors affecting the column efficiency.     

分子印迹技术在黄曲霉毒素检测中的最新研究进展EI北大核心CSCD

黄曲霉毒素(AFT)是由黄曲霉和寄生曲霉等某些菌株产生的一类真菌毒素,主要包括B1,B2,G1,G2,M1,M2,GM,P1,Q1,毒醇等,其中B1的毒性最大,致癌性最强,其广泛存在土壤、动植物、各种坚果、谷物,奶,食用油及其制品中,因此,食品中超痕量及痕量的黄曲霉毒素的检测方法受到高度关注。由于农产品样品基质复杂,而黄曲霉毒素含量和限量极低,高效特异性样品前处理技术是高灵敏精准检测黄曲霉毒素的关键之重。近年来分子印迹技术在样品前处理和核心识别元件等方面发展迅猛,在黄曲霉毒素痕量检测方面凸显出一定优势。综述了近几年来分子印迹技术在黄曲霉毒素前处理及快速检测等方面最新研究进展,并展望了分子印迹技术在黄曲霉检测应用的发展前景。     

Recent advances in polymer molecular dynamics simulation and data analysis

Significant advances in molecular simulation methodology over the past decade have greatly reduced the traditional size-timescale bottleneck in molecular dynamics calculations. The development of the geometric statement function method allows for systems up to several hundred thousand atoms to be simulated for up to several nanoseconds in reasonable times on standard workstations. For constant energy simulations, the use of symplectic integrators ensures accurate dynamics, even at long simulation times, without velocity or other artificial rescaling schemes. Finally, new methods of frequency estimation allow for accurate vibrational mode frequency calculations even in the presence of chaotic motion on time scales twenty times shorter than the standard fast Fourier transform, with an additional improvement in the sensitivity of the results when initial dynamics conditions are carefully chosen.     

Recent advances of application of porous molecular cages for enantioselective recognition and separation

Porous materials with well‐defined pore structures have received considerable attention in the past decades due to their unique structures and wide applications. Most porous materials such as zeolites, metal‐organic frameworks, covalent organic frameworks, and porous organic polymers are extended to infinite frameworks or networks by robust covalent or coordination bonds. Porous molecular cages composed of discrete molecules with permanent cavities are an emerging class of porous material and the discrete molecules assemble into solids by weak intermolecular interaction. In comparison to porous extended solids such as metal‐organic frameworks and covalent organic frameworks, porous molecular cage solids are generally soluble in organic solvents thus allowing solution processing, making them more convenient to apply in many fields. This review mainly focuses on the recent advances of application of porous molecular cages (porous organic cages and metal‐organic cages) for enantioselective recognition and separation from 2010 to present, including gas chromatography, capillary electrochromatography, chiral fluorescent recognition, chiral potentiometric sensing, and enantioselective adsorption. Furthermore, the two important family members of porous molecular cages, porous organic cages and metal‐organic cages, are also discussed.     

分子印迹技术在蛋白质分离分析中的研究进展

蛋白质结构复杂,种类多样,与各种生命活动密切相关。大部分蛋白质在生物体中含量极低,对其分析检测带来极大困难。因此实现复杂生物样品中蛋白质的选择性识别与分离,对实现蛋白质的分离分析意义重大。通过分子印迹技术制备的分子印迹聚合物含有与模板分子大小、形状一致,官能团相互匹配的三维印迹空穴,在蛋白质的选择性识别与分离领域显示出了巨大的发展潜力。但是,由于蛋白质具有尺寸较大、构型易变、结构复杂等特点,分子印迹技术在蛋白质印迹中面临着巨大挑战。该文在介绍几种新型分子印迹技术包括表面印迹、抗原决定基印迹和金属螯合物印迹的基础上,综述了近3年分子印迹技术在蛋白质分离分析方面的应用,并对其发展进行了总结与展望。