PDMS夹心式电泳微芯片的研究

电泳微芯片由于具有自动化程度高、试剂消耗少和分析速度快等优点,目前已经成为微全分析系统研究的热点.     

高效毛细管电泳用于以聚环氧乙烷为筛分介质分离DNA的机理研究

用毛细管电泳以聚环氧乙烷(PEO)为筛分介质对pUC19DNA/Msp Ⅰ(HpaⅡ)Marker中的12条DNA片段进行了分离,并尝试用Ogston模型、爬行模型以及线性模型对分离机理进行研究,最终发现26～147bp的小片段,在低电场强度时能很好地符合Ogston模型理论,而190～501bp中等长度的DNA片段电泳迁移率与其尺寸间存在很好的负相关的线性关系,为此,提出一种新的线性模型来进行解释.此外,还探讨了PEO的浓度和电场强度对分离的影响.其结论可更好地从理论上指导对中小片段DNA的分离,对肿瘤基因突变点的分析和PCR扩增产物的分离分析具有重要的意义.     

聚环氧乙烷无胶筛分毛细管电泳分离宽分子量范围DNA片段

在无胶筛分毛细管电泳中,以聚环氧乙烷为筛分介质,用硅烷化处理的毛细管柱（31.2 cm×75 μm有效长度21.0 cm）分离DL5000 DNA Marker（DNA长度为100~5000 bp）,研究筛分介质浓度、缓冲液pH、分离电压和溴化乙锭浓度对分离双链DNA片段的影响,优化出分离100~5000 bp DNA片段的最佳条件。毛细管电泳的最佳条件为PEO浓度0.5%、缓冲液pH值8.0、电压12 kV、溴化乙锭浓度3.0 μg/mL。此条件下,对山梨醇脱氢酶基因（SDH）和乙烯受体基因（ETR1）的聚合酶链式反应（PCR）扩增产物同时检测,分离、鉴定效果良好。     

DNA Sequencing by Capillary Electrophoresis Using Quasi-interpenetrating Network Formed by Polyacrylamide and Poly（N-hydroxymethylacrylamide）

Capillary electrophoresis (CE) in conjunction with laser induced fluorescence (LIF) is a powerful tool for DNA sequencing1. A number of water-soluble polymers have been used for this purpose. We have recently reviewed studies on separation medium on DNA s…     

用于毛细管电泳分离DNA的聚合物介质的研究进展

综述了用于毛细管电泳分离DNA及测序的聚合物介质的研究进展。这类聚合物主要有均聚物、无规共聚物、嵌段共聚物、接枝共聚物、共混聚合物、准互穿聚合物网络和微交联纳米凝胶聚合物,并对各种结构的聚合物的筛分性能进行了比较。     

用于毛细管电泳DNA分离的合成聚合物*

毛细管电泳的无胶筛分方法在DNA片段分离、DNA 测序方面取得了显著的成绩并已成功应用于人类基因组计划.该法是在毛细管柱中充入一定浓度和组成的线性高分子溶液,利用其对样品组分电泳迁移时的阻滞作用,按分子量大小对DNA等生物大分子进行筛分分离分析.因此,聚合物筛分介质的类型、组成和性质会显著影响分离效果.近年来,由于受到基因组计划的影响,出现了许多用于DNA片段分离和DNA测序的水溶性高分子聚合物,并取得很大进展.本文按照均聚物和共聚物的分类,综述了作为筛分介质的各种合成聚合物及其应用效果,并简要介绍了有关的筛分理论和分离的评价指标.     

毛细管电泳紫外检测条件下单碱基分离DNA片段

合成了一种水溶性聚合物,聚N,N-二甲基丙烯酰胺(PDMA)和聚乙烯吡咯烷酮体系(PVP),并用于DNA分离.优选该体系溶液含量为2.0% PDMA+2.0% PVP,在紫外检测的条件下,对标准DNA酶切片段pBR322/Hae Ⅲ样品进行分离,其中123/124碱基对的分离度(R_s)为0.72.加入甲酰胺(φ≥0.10)对DNA样品进行去活处理后,该体系亦能对单链DNA片段中的123/124进行分离,分离度(R_s)为0.75.实验还显示进样时存在浓缩效应.本体系粘度较小,筛分能力强,具备芯片毛细管DNA分离介质的潜力.     

添加剂在毛细管电泳分离DNA中的作用研究进展

使用无胶筛分介质的毛细管电泳（包括毛细管阵列电泳和微芯片电泳）是最重要的DNA分离技术之一。在低粘度的无胶筛分介质中加入某种添加剂是一种有效且简单的克服填充困难和提高DNA分离性能的方法。本文就各种添加剂（如多羟基化合物、粘土、金纳米粒子、乳胶粒等）对提高无胶筛分介质中DNA的分离性能的作用进行了综述。     

毛细管电泳无胶筛分介质分离DNA的机理

快速、高效而灵敏的分离技术对于DNA的分析是至关重要的。使用无胶筛分介质的毛细管电泳是最重要的DNA分离技术之一,通常使用无交联的高分子溶液作为无胶筛分介质。本文在介绍高分子溶液理论的基础上,综述了DNA在毛细管电泳无胶筛分介质(缠结溶液和稀溶液)中的分离机理,主要包括Ogston筛分模型、各种修正的爬行模型、瞬态缠结偶合机理及其改进机理等。     

毛细管电泳无胶筛分介质分离DNA的机理

快速、高效而灵敏的分离技术对于DNA的分析是至关重要的。使用无胶筛分介质的毛细管电泳是最重要的DNA分离技术之一,通常使用无交联的高分子溶液作为无胶筛分介质。本文在介绍高分子溶液理论的基础上,综述了DNA在毛细管电泳无胶筛分介质（缠结溶液和稀溶液）中的分离机理,主要包括Ogston筛分模型、各种修正的爬行模型、瞬态缠结偶合机理及其改进机理等。     

DNA Separation by Capillary Electrophoresis with Ultraviolet Detection using Mixed Synthetic Polymers

The mixtures of two polymers, poly (N,N-dimethylacrylamide) (PDMA) and polyvinylpyrrolidone (PVP) were synthesized and used as the separation medium for double-stranded and single-stranded DNA fragments by capillary electrophoresis with UV detector. On optimal conditions, 2%w/v PDMA 2%w/v PVP can be used to separate the doublet 123/124bp in pBR322/Hae Ⅲ Markers.     

聚乙烯吡咯烷酮动态涂敷毛细管电泳柱分离碱性蛋白质

以聚乙烯吡咯烷酮(PVP)为添加剂对毛细管柱进行动态修饰,用于碱性蛋白分离。对4种碱性蛋白质进行分离,实验结果表明聚乙烯吡咯烷酮能够很好地抑制电渗流(EOF)及碱性蛋白在石英毛细管壁上的吸附作用。在pH4.0,PVP浓度(W/V)为0.4％时,EOF仅为1.35×10~(-9) m~2/V.s,平均柱效可达5×10~5理论塔板数/m。每次运行之间(n=6),天与天之间(n=6),迁移时间的相对标准偏差(RSD％)分别小于1％和3％,表明该动态涂敷方法具有良好的重现性和稳定性。另外,由于PVP的粘度较小,使得该方法操作方便、快捷。     

两亲型聚L-亮氨酸-聚乙二醇单甲醚嵌段共聚物的合成与表征

开环聚合;生物降解共聚物;两亲型聚L-亮氨酸-聚乙二醇单甲醚嵌段共聚物的合成与表征     

手性药物的毛细管电泳拆分

以氧氟沙星、扑尔敏、特布它林和普萘洛尔为手性药物,分别采用羟丙基-β环糊精(HP--βCD)、羟丙基-β-环糊精结合羧甲基-β-环糊精(HP--βCD/CM--βCD)作手性拆分试剂,考察环糊精浓度和pH对手性选择性的影响。结果发现环糊精提供手性相互作用,而pH强烈地影响这种相互作用。以HP--βCD/CM-β-CD组成的双环糊精系统能更好地优化手性选择性,而通过调节pH可以获得需要的分离选择性、迁移次序。     

微流体芯片电泳技术对人血清蛋白的快速分离

通过微流体芯片电泳技术分离人血清蛋白,探讨了常见十字形微流体芯片上样品的电动进样与分离过程,分析了在十字芯片上的进样时间和电压设置对后续样品检测和定量的影响。采用的缓冲体系为:100mmol/L H3BO3,50mmol/L NaCl,5%Dextran(以NaOH调至pH 8.3),该缓冲液能够有效分离人血清蛋白中的白蛋白(Albumin)和4种球蛋白(α1-,α2-,β-,和γ-globulin),并且给出了它们在该缓冲体系中的淌度估算范围为5.15×10-5～47.2×10-5 cm2/(V.s)。在芯片上2min之内可以完成进样和分离,相比于常用的毛细管区带电泳,提高了分析速度。     

高效毛细管电泳分离手性物质

本文对近年来发展起来的高效毛细管电泳技术（ＨＰＣＥ）在手性分离方面的工作做了评述，讨论了高效毛细管电泳手性对映体的分离方式和定量方面，并对在这一重要领域中可能的发展趋势做了展望。     

An Observation on the Microphase Separation of Poly(methyl methacrylate)-block-Polystyrene Copolymer

The well-ordered structures of block copolymer formed by self-assemble have attracted much attention as potentially interesting optical materials, especially as photonic crystals1,2. In order to achieve desirable photonic crystal properties, the morphologies of block copolymers should be controlled, including obtaining the correct size of domains for the optical frequencies of interest and attainment of long-range domain order and appropriate orientation. We know that the morphology of one blo…     

Structural Transitions in Triblock Copolymers Based on Poly(ethylene oxide) and Polyacrylamide under the Temperature Influence

Thermal transitions in the bulk structure of triblock copolymers (PAA-b-PEO-b-PAA) based on polyacrylamide and poly(ethylene oxide) with varying molecular weight (length) of PEO block comparing with the structures of individual polymers and polymer mixtures were investigated. A lot of effects, such as the melting temperature depression, decreasing of the crystallinity degree of PEO and also appearance of the microphase separation in amorphous regions of the polymer mixtures and the triblock copolymers were found. Such investigations pointed to a strong intramolecular interaction of the polymer blocks in the triblock copolymers that is confirmed by the results of IR spectroscopy. It was shown that PEO and PAA blocks formed the system of H-bonds with participant of trans-multimers of amide groups.     

Chiral Separation of Ofloxacin Enantiomers by Microchip Capillary Electrophoresis with Capacitively Coupled Contactless Conductivity Detection

We describe a chiral separation method for ofloxacin enantiomers, levofloxacin and dextrofloxacin by microchip capillary electrophoresis with capacitively coupled contactless conductivity detection. The running buffer included 1 mmol L^?1 MES and 1 mmol L^?1 Tris (pH 8.0) with a separation voltage of 1.5 kV and an injection time of 10s. Under these conditions, the enantiomers were completely separated within 1 min. The linear calibration curves were A = 5.76 c — 0.00587 for levofloxacin and A = 5.41 c — 0.00551 for dextrofloxacin, in which the linear concentration of the components all ranged from 0.05 to 0.15 mg mL^?1 (regression coefficients were both 0.9996). The limits of detection (S/N = 3) were, respectively, 18 and 21 μg mL^?1. The relative standard deviations of migration time were both 2.0% (n = 6). The relative standard deviations of peak area were 3.4% (n = 6) for levofloxacin and 4.0% (n = 6) for dextrofloxacin. The effects of some factors on resolutions, such as separation voltage and injection time, concentration of running buffers, were studied. The method was simple, rapid, high‐efficient. Furthermore, the method could be applied to the chiral separation of the product containing these enantiomers, such as Ofloxacin Eye Drops.     

Control of Microphase Separation of Polystyrene-Silica Nanocomposites by Using Perhydropolysilazane and Partially Epoxidized Poly(styrene-block-butadiene-block-styrene)

In order to control microphase separation of polystyrene-silica nanocomposites, perhydropolysilazane (PHPS), which is a preceramic of silica, and epoxidized poly(styrene-block-butadiene-block-styrene) triblock copolymer [E-SBS, M_w = 8.0 × 10⁴, styrene: 40 mol%, degree of epoxidization of butadiene: 20 mol%] or poly(styrene-block-butadiene-block-styrene) triblock copolymer [SBS, M_w = 1.40 × 10⁵, styrene: 30 mol%] as templates of microphase separation were blended, following the calcination of composites in steam at 60°C. Well-arranged microphase separation was formed with E-SBS, though the macrophase separation was formed with SBS. The morphology of the microphase separation of the composites with E-SBS and PHPS was widely controlled by varying the PHPS content based on Molau's law. Silica domains were formed in polybutadiene domains. NMR analysis indicated the interaction between silanyl group of PHPS and epoxy group in E-SBS. The composites on the substrate were highly transparent and the surface of the composite with 73.5 vol% of silica was harder than 4H.