2020年毛细管电泳技术年度回顾

该文为2020年毛细管电泳(capillary electrophoresis, CE)技术年度回顾。归纳总结了以“capillary electrophoresis-mass spectrometry”或“capillary isoelectric focusing”或“micellar electrokinetic chromatography”或“capillary electrophoresis”为关键词在ISI Web of Science数据库中进行主题检索得到的2020年CE技术相关研究论文222篇,以及中文期刊《分析化学》和《色谱》中CE技术相关的研究论文37篇。对2020年影响因子(IF)≥5.0的Analytical Chemistry, Food Chemistry, Analytica Chimica Acta和Talanta等13本期刊的38篇文章报道的科研工作作了逐一介绍;对IF<5.0的期刊中CE技术报道较为集中的Journal of Chromatography A和Electrophoresis两本分析化学类期刊发表40篇文章中的代表性内容作了综合介绍;对重要的中文期刊《分析化学》出版的“核酸适配体专刊”和《色谱》出版的2期CE技术专刊所收录的37篇文章中的工作作了总体介绍。总体来说,2020年CE技术发展趋势仍以毛细管电泳-质谱(CE-MS)的新方法和新应用最为突出,主要集中在CE-MS与电化学检测、固相萃取以及多种毛细管电泳模式的联用方面,CE-MS接口相关的报道较前几年有所减少;常规CE技术则以胶束电动毛细管色谱(MEKC)在复杂样本分析、浓缩富集应用为主,尤其在食品和药品等复杂基质样本分析方面的报道较为集中;此外,我国CE相关领域专家学者的科研成果涵盖了CE在生命科学、临床医学、医药研发、环境科学、天然产物、食品分析等领域的应用,代表了国内CE科研应用水平和现状。     

2022年毛细管电泳技术年度回顾

该文为2022年毛细管电泳(capillary electrophoresis, CE)技术年度回顾。归纳总结了以“capillary electrophoresis-mass spectrometry”或“capillary isoelectric focusing”或“micellar electrokinetic chromatography”或“capillary electrophoresis”为关键词在ISI Web of Science数据库中进行主题检索(排除“capillary electrochromatography”“microchip”“microfluidic”“capillary monolithic column”)得到的2022年CE技术相关研究论文881篇。重点介绍了影响因子(IF)大于10.0的Lancet Global Health,ACS Central Science,Microbiome,Trends in Food Science&Technology,TrAC-Trends in Analytical Chemistry,Jou...     

阳离子纤维素-十二烷基苯磺酸钠的拟聚阴离子研究

采用浊度法、 表面张力法、 zeta电位法和毛细管电泳法(CE)研究了典型的阳离子纤维素(JR400)与典型的阴离子表面活性剂十二烷基苯磺酸钠(SDBS)之间的缔合作用. 浊度法和zeta电位法实验结果表明, 在等电区附近产生的沉淀区随JR400浓度减小而变窄, 加入过量SDBS后沉淀消失, 而且发现阳离子纤维素同系物的分子量和取代度对结果的影响较小. 表面张力法实验结果显示, 该类复合体系的表面张力曲线表观上与典型“中性聚合物-阴离子表面活性剂”体系相似, 具有3个拐点(但第二拐点易被沉淀区覆盖)且SDBS与阳离子纤维素间形成缔合物. zeta电位法实验结果表明, 沉淀区前少量SDBS存在时该缔合物具有正电位, 因而维持聚阳离子特性; 沉淀区后过量SDBS存在时该缔合物具有负电位, CE分析进一步证明其为拟聚阴离子. 上述实验结果和结论对研究该类复合体系具有较大理论意义和实用价值.     

锂硫电池中的催化作用

锂硫电池理论能量密度高达2600 Wh·kg^-1,单质硫的理论容量可达1675 mAh·g^-1,远高于商业化的锂离子电池正极材料,但多硫化锂的“穿梭效应”等问题对其性能影响严重。目前研究主要采用基于“阻挡”的物理限制和化学吸附策略将多硫化锂限制在正极侧。而基于“疏导”的催化转化策略则通过加快氧化还原反应动力学,在抑制“穿梭效应”的同时实现降低过电位、诱导Li₂S均匀沉积等功能。本文综述了锂硫电池中的催化作用,基于是否产生氧化还原中间体将其分为吸附-转化机制和氧化还原介导机制两类;并介绍了相关的材料及常用的表征技术和研究方法。     

“蛋黄蛋壳”结构纳米电极材料设计及在锂/钠离子/锂硫电池中的应用

“蛋黄蛋壳”结构纳米材料,具有易于调控的“蛋黄”、“蛋壳”和“空腔”结构,可视作“纳米反应器”,在催化、储能等领域表现出显著的应用潜力。尤其在电化学能源存储和转换方面,该结构纳米电极具有大的比表面积和独特的核壳结构,在充放电过程中可缓解电极的体积变化,提供快速的离子/电子输运通道,强化中间产物的吸附和提升转换反应效率等,能显著提高电极稳定性、倍率性能和循环性能,是一类较为理想的电极材料。本文针对“蛋黄蛋壳”结构纳米电极在锂/钠离子电池、锂硫电池等新兴二次电池领域的实际应用,总结了具有该结构纳米电极的设计与合成策略,包括:模板法、奥斯特瓦尔德熟化、电化学置换、克肯达尔效应等,评述了各种策略的优缺点以及电极材料的应用进展,最后对该类材料在锂/钠体系及锂硫电池二次电池方面的研究与应用前景进行了展望。     

桥连对嵌段共聚物自组装的调控

通过嵌段共聚物自组装形成“桥连”是制备具有优异力学性能的网络结构的有效途经, 具有重要的应用价值. 但是, 过去的研究工作很少讨论“桥连”对嵌段共聚物自组装行为本身的影响. 该研究评论主要总结了最近几年利用“桥连”对嵌段自组装行为进行调控的工作进展. 作者设计了BABCB三组分线性多嵌段共聚物, 当其自组装形成二元“介观晶体”(球、柱)结构时, 中间B嵌段连接A和C相区(嵌段聚集成的“大原子”), 自然地形成桥连; 减小中间桥连B嵌段的相对长度, 就可以增加其拉伸程度, 从而降低介观晶体的配位数; 另外, 两个末端B嵌段的相对长度可以直接调控A和C“大原子”之间的相对配位数. 基于这两个机理, 自洽场理论计算预测了各种配位数相等和不相等的二元介观晶体结构. 进一步, 将“拉伸桥连”概念拓展到AB型嵌段共聚物体系中, 并且通过多臂星型嵌段共聚物分子结构中的“组合构型熵效应”在AB型嵌段共聚物中形成高比率的桥连构型, 使传统的六角柱状结构转变为了四配位的四方柱状和三配位的石墨烯类柱状结构. 未来, 在ABC三组分嵌段共聚物体系的设计中引入拓扑结构以及使用共混等方法, 有望在介观尺度重铸大多数已知的原子/离子二元晶体结构, 甚至超越原子/离子晶体结构.     

《色谱》2015年版影响因子蝉联化学类第一名 两篇文章入选中国百篇最具影响国内学术论文

<正>2015年10月21日,《2015年版中国科技期刊引证报告(核心版)》在北京发布,《色谱》期刊2014年度主要计量指标再获佳绩。影响因子为1.954,连续第六年在中国化学类核心期刊中排名第一,在包括2312种中文期刊和71种英文期刊的中国科技核心期刊中排名第二十一。另外,《色谱》两篇论文入选本年度中国百篇最具影响国内学术论文。     

从铜离子、酸中心与铝分布的关系分析不同模板剂制备Cu-SSZ-13的NH3-SCR性能

铜离子改性的SSZ-13沸石是以氨气为还原剂选择催化还原柴油发动机尾气中氮氧化物反应(NH₃-SCR)的优良催化剂。本文综述并具体分析了酸中心位点对于Cu-SSZ-13中铜离子落位、迁移的影响,以及骨架铝分布对其决定性的作用,强调了“成对”酸中心,“强铝对”对于催化剂水热稳定性的重要作用,并总结了目前控制“铝对”形成的方法。以此为基础分析了不同有机模板剂、共模板剂法制备的Cu-SSZ-13在催化NH₃-SCR反应中的表现,为使用廉价模板剂或共模板剂替代TMADaOH合成具有良好NH₃-SCR催化活性和水热稳定性的Cu-SSZ-13提供参考。     

我刊在1998年化学类科技期刊影响因子排序中居第4名

期刊名称学科分类：化学总被引频次９６,９７年发表论文（篇）９６,９７年论文在９８年被引次数影响因子９８年发表论文（篇）９８年发表论文当年被引次数即年指标基金论文数自引总引比分析试验室９３６３０７３３３１．０８５１５７２１０．１３４３８０．４２分析化学２３８８６６８６７０１．００３３３４５７０．１７１１５１０．１３色谱４９０３３８２３４０．６９２１６８７０．０４２６２０．２１分析测试学报３４４２５３１５１０．５９７１５６１９０．１２２６１０．０６环境化学４３３１８９１１００．５８２１０５１２０．１…     

石墨烯迷你马达的自组装制备及其乙醇驱动运动和油品吸附性能

石墨烯三维(3D)宏观体多集中在厘米尺度并为实心对称结构,且存在“小尺寸”和“低密度”难以协调的矛盾。 本文以氧化石墨烯为前驱体、苯胺为交联剂,在电动搅拌下通过剪切力驱动聚集和毛细管力干燥协同自组装制备球状氧化石墨烯水凝胶,经过高温还原得到石墨烯迷你马达。 所得石墨烯迷你马达具有尺寸小(直径2~5 mm)、密度低(0.2~0.7 g/cm³)、内部空心结构以及疏水亲油的性能。 上述结构特征赋予其乙醇驱动运动和油品吸附性能。 研究表明,充分浸泡乙醇的石墨烯迷你马达在水中可以展现出自转速度3 r/s的无规则快速运动;对水中植物油的饱和吸附量约为794.9 mg/g。     

Rapid determination of drugs in biofluids by capillary electrophoresis Measurement of antipyrine in saliva for pharmacokinetic studies

A micellar electrokinetic capillary chromatography method was developed that permitted the resolution of antipyrine from endogenous compounds and its quantitation in neat saliva in as little as 1 min. Final conditions were: SpectraPhoresis 1000, 30(23) cm × 50 μm silica capillary, 50 mM sodium phosphate pH 9.6, 50 mM SDS, 10 s hydrodynamic load, detection scanning 200–300 nm or 260 nm, run 25 kV. To overcome the effects of Joule heating the capillary was cooled to 15°C. Sensitivity was <10 μM and linearity extended to 350 μM. Comparison with an HPLC assay demonstrated that hydrodynamic injection gave a loading bias unless samples and standards were of equal viscosity. For 75 samples from five subjects the correlation of CE vs. HPLC was then r = 0.99.     

Capillary electrophoresis—matrix-assisted laser-desorption ionization mass spectrometry of proteins

An “off-line” combination of capillary electrophoresis (CE) with matrix-assisted laser-desorption mass spectrometry (MALDI-MS) has been developed for the structural characterization of CE-separated peptides and proteins. Using a sheath flow interface, similar to that developed for “on-line” CE—fast atom bombardment MS and CE—electrospray MS, an efficient sample isolation procedure has been developed which is applicable to bioorganic compounds in aqueous buffer solutions. This isolation procedure, with subsequent transfer to the MALDI-MS sample target, has been successfully used for the direct analysis of CE-separated proteins of M _r up to 67 000, and a mixture of apolipoprotein AII monomer and homodimer, using sample amounts of less than 1 pmol.     

Simultaneous determination of purine bases, ribonucleosides and ribonucleotides by capillary electrophoresis-electrochemistry with a copper electrode

Simultaneous determination of purine bases, ribonucleosides and ribonucleotides was achieved by coupling capillary electrophoresis (CE) with wall-jet amperometric detection. A 200 μm diameter copper disk electrode was applied at working potential, +0.65 V vs. saturated calomel electrode. The current response of high sensitivity and stability was obtained in strong basic solutions which were suitable for satisfactory CE separations. The calibration curve was linear over 2–3 orders of magnitude and the limits of detection for adenine, guanine, xanthine, uric acid, adenosine, guanosine, adenosine-5′-monophosphate and guanosine-5′-monophosphate were below 9 fmol (S/N=3). The use of this method for the separation and detection of compounds present in human plasma samples was reported.     

Determination of melatonin in biological samples by capillary electrophoresis

The determination of melatonin (MLT) in physiological samples was investigated using capillary electrophoresis (CE). Mouse blood was collected in tubes containing EDTA, centrifuged at 1500 g for 20 min at 4°C, and stored at −20°C. Plasma samples were extracted with dichloroethane, centrifuged and the aqueous phase was discarded. Then the organic phase was evaporated to dryness. The residue was dissolved in deionized water and filtered with a microfilter (0.22 μm). Separations were carried out using a CE system equipped with a fused silica capillary [80 cm (effective length 52 cm)×75 μm I.D.] and an ultraviolet–visible detector (200 nm), and programmed to provide 25 mM 2-(N-morpholino)ethanesulfonic acid (pH 5.7). Injection was performed hydrostatically by elevating the sample by 10 cm at the cathodic side of the capillary. The calibration curve, reproducibility, recovery and limit of detection were examined, and validation of the method was performed. The result showed that MLT in blood could be easily determined with the new method.     

Determination of orotic acid in urine by capillary zone electrophoresis in tandem-coupled columns with diode array detection

Analytical potentialities of capillary zone electrophoresis in the separation system with tandem-coupled columns to the spectral identification and determination of orotic acid (OA) in urine by diode array detection (DAD), coupled to the separation system via optical fibers, were investigated. A very significant “in-column” clean-up of OA from urine matrix was reached in the separation stage of the tandem by combining a low pH (2.8) with complexing effects of electroneutral agents [- and β-cyclodextrins, poly(vinylpyrrolidone) and 3-(N,N-dimethyldodecylammonio)propanesulfonate]. Due to this, its DAD spectral data could be acquired in the detection stage of the tandem with almost no disturbances by matrix co-migrants. The concentration limits of detection obtained under such working conditions for a 200-nl sample load of OA and 320 μm I.D. capillary tubes were 3.5 μmol/l (218 nm) and 0.4 μmol/l (280 nm). Using chemometry procedures (target transformation factor analysis, fixed size moving window-evolving factor analysis, orthogonal projection approach and fixed size moving window–target transformation factor analysis) in processing of the acquired spectral data, the presence of OA in the loaded urine matrix could be confirmed with confidence when its concentration was 10 μmol/l or slightly less.     

pH可逆激活型不对称菁光敏剂的光动力杀菌活性

研究了一种pH可逆激活型不对称菁(Acy)的光动力杀菌性能。 结果表明,Acy在细菌所处弱酸性微环境和808 nm激光照射下可特异性激活产生单线态氧,对大肠杆菌和金黄色葡萄球菌均展现出了很好的光动力杀菌效果,而在正常体液条件下无明显的抗菌作用。 这种可特异性激活的光动力特性使得Acy避免了传统光敏剂因缺乏细菌特应性而产生的非特异性损伤,在细菌感染的特异性治疗方面展现出了良好的应用前景。     

Moment Analysis in Non-Linear Frontal-Elution and Elution Chromatography

Analytical formulae are presented for the statistical moments of an output chromatographic curve for non-linear distribution isotherms at a very narrow feed band (“elution chromatography”). Non-linear “frontal-elution chromatography”, i.e., the case of a very wide feed band, is also considered. The analytical expressions characterize the position and the width of sorption and desorption boundaries of the output curve. The column length at which a constant configuration of the sorption (or desorption) boundary is attained is dependent in the curvature of the isotherm and on the plate height. The results have been confirmed experimentally.