高效毛细管电泳-电堆积柱上富集法分离与测定5种药品中布洛芬的含量

建立高效毛细管电泳-电堆积柱上富集法分离与测定5种药品中布洛芬含量的方法。在220nm波长处以间苯二酚为内标物,分离电压为20kV,分离温度为25℃,用10mmol·L-1硼砂缓冲液(pH=9.2)作毛细管电泳的运行液,被测组分与内标物得到快速分离。布洛芬的进样浓度在10～400mg·L-1范围内与电泳峰面积呈良好的线性关系,r=0.9997,平均回收率100.9%,最低定量浓度为0.35mg·L-1。该方法简捷、快速、重现性好,可用于布洛芬药物的质量控制。     

酸度对毛细管区带电泳分离蛋白质的影响分析

研究了不同酸度下的毛细管区带电泳分离牛血清白蛋白和溶菌酶混合物。比较了两种酸度下 ,毛细管电泳分离谱图、分离原理以及分离重复性的不同 ,描述了毛细管区带电泳对于蛋白质的分离机制     

毛细管电泳-激光诱导荧光检测测定脑啡肽方法的建立及其应用

建立脑啡肽(ENK)柱前荧光素异硫氰酸盐(FITC)衍生化,毛细管区带电泳-激光诱导荧光检测(CZE-LIF)测定的方法,并对FITC衍生化的影响因素和毛细管电泳的分离条件进行优化.毛细管电泳的分离条件为:75 μm(内径)×67 cm石英毛细管柱;60 mmol/L pH 9.4 Tris-硼砂缓冲液;电压350 kV/cm;柱温25℃;压力进样3 s;LIF检测,λex/λem为488/520nm.以脑啡肽(ENK)标准品的浓度和电泳峰面积建立标准工作曲线,得到回归方程A=0.494 66 0.085 92c,线性范围是35.2～563.1 fmol/μL,(n=7),r=0.998 5,检测限为1.6×10-15 mol/μL(S/N=3).大鼠脑部微透析液样品中脑啡肽应用此方法测定含量为7.4×10-15 mol/μL.     

高效毛细管电泳分离水样中的硝基苯类化合物

利用高效毛细管电泳（HPCE）同时分离水样和印染废水中的3,5-二硝基苯甲酸、对硝基苯甲酸、对硝基苯酚等硝基苯化合物。通过考察缓冲液类型及浓度（10~50mmol.L-1）、pH值（7.0~9.5）、分离电压（10~30kV）、进样时间（2~10s）等因素对分离效果的影响,建立了水样中硝基苯类化合物的快速分离测定方法。得到的合适的电泳条件为硼砂缓冲液20mmol.L-1、pH值9.2、电泳电压25kV、进样时间4s。将该分离方法应用于实际印染废水中的硝基苯类化合物的分离测定,结果表明该方法快速、准确、重现性好。     

毛细管电泳法测定水飞蓟宾的含量

采用高效毛细管电泳法(HPCE)测定水飞蓟宾的含量.以未涂敷熔融石英毛细管柱(50 cm×75μm,有效长度45 cm)作为分离通道,缓冲溶液为10 mmol·L-1硼砂(pH为6.0),分离电压为15 kV,检测波长288 nm,虹吸进样,高度差10 cm,进样10 s,柱温25℃的条件下,水飞蓟宾分析时间在4 mi...     

6种苯甲酸类化合物的HPCE优化分离

应用高效毛细管电泳法,采用正交设计法优化实验条件,通过两种常用电泳模式--区带毛细管电泳法和胶束电动毛细管色谱法对6种笨甲酸类化合物的分离进行了研究,确立了最佳分离条件.该方法快速、可靠、效果好.     

感应草多糖的化学组成与生物活性研究

对感应草多糖的化学组成与生物活性进行研究,采用水提醇沉法、脱色脱蛋白透析处理,得到粗多糖、脱色多糖和精制多糖,测定多糖的主成分含量,采用薄层色谱法(TLC)及柱前衍生化-高效液相色谱法(HPLC)分析多糖的单糖组成,测定多糖对DPPH·和ABTS~+·的清除能力、还原能力以及对α-葡萄糖苷酶和DPP-Ⅳ酶的体外抑制作用。感应草多糖由5种单糖组成,对DPPH·和ABTS~+·均有清除作用,具有还原能力,对α-葡萄糖苷酶和DPP-Ⅳ酶均有抑制作用。相关性分析表明,多糖的糖含量、糖醛酸含量、还原糖含量和蛋白质含量与其抗氧化活性、α-葡萄糖苷酶抑制活性均无显著相关性。感应草多糖具有抗氧化活性和α-葡萄糖苷酶及DPP-Ⅳ酶抑制活性。     

两种毛细管电泳方法分析重组人促红素异构体含量的比较

目的全柱成像毛细管等电聚焦电泳(whole column imaging detection-capillary isoelectric focusing electrophoresis,WCID-CIEF)及毛细管区带电泳法(capillary zone electrophoresis,CZE)检测分析重组人促红素(recombinant human erythropoietin,rhEPO)异构体含量。方法 5批rhEPO原液同时经WCID-CIEF法(采用4 mol/L尿素,0. 35%甲基纤维素,4%两性电解质混合溶液作为样品缓冲液,聚焦电压为3 k V,预聚焦时间1 min,聚焦时间7 min,成像波长280 nm)及CZE法(采用0. 01 mol/L NaCl、tricine、NaAC和7 mol/L Urea及2. 5 mmol/L腐胺混合溶液作为电泳缓冲液,pH 5. 55,进样压力3. 45 kPa,进样时间10 s,分离电压15. 4 kV,分离时间80 min,检测波长214 nm)检测分析异构体含量。结果 WCID-CIEF及CZE法测定5批rhEPO原液均有5～8条异构体条带,异构体含量差异无统计学意义(P 0. 05),具有明显的相关性(r为0. 999),各峰面积占比相差总和小于3%。结论虽然WCIDCIEF谱图及CZE谱图的含义略有不同,但两种毛细管电泳方法的分析结果基本相同,均可满足rhEPO异构体的质量控质需求。     

苯并三氮唑的毛细管区带电泳测定

建立了应用毛细管区带电泳测定水处理剂和循环冷却水中苯并三氮唑含量的方法.选择的分离和测定条件为:采用pH=9.1、浓度为20mmol/L的硼砂缓冲溶液体系,脱氢乙酸钠为内标物,检测波长200nm,分离电压25 kV,分离温度25℃,压力进样时间20 s.该法线性范围为0.10～48 mg/L,回收率＞98.1%.该法简便、快速、准确,对实际样品的测定结果令人满意.     

人参多糖的分离纯化及其单糖组成分析

以人参为原料,研究人参多糖分离纯化方法得到均一多糖,并对其相对分子质量、单糖组成、红外光谱(Infrared,IR)进行分析。利用三氯乙酸法(Trichloroacetic Acid,TCA)除蛋白,再经DEAE-Cellulose-52柱和HW-55F凝胶柱分离纯化获得均一组分PGS1-1。采用凝胶柱层析法测定其相对分子质量,高效液相色谱与蒸发光散射检测器联用及IR研究PGS1-1的单糖组成及基本结构。研究表明三氯乙酸除蛋白最佳工艺条件为料液比1∶2,三氯乙酸(TCA)浓度12%,作用时间60 min,此条件下测得蛋白脱除率与多糖保留率综合得分87.80。分离纯化得到PGS1-1组分,其相对分子质量为2.8×104Da,主要由葡萄糖、半乳糖、鼠李糖、阿拉伯糖组成,物质的量比为0.34∶0.27∶1.44∶0.42,IR证明PGS1-1具有吡喃型β-糖苷键的多糖特征峰,为人参多糖的分离纯化及单糖组成提供了理论依据。     

Insect antifeedant properties of anthranoids from the genusVismia

Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.     

2007～2008年世界塑料工业进展

收集了2007年7月～2008年6月世界塑料工业的相关资料,介绍了2007～2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.     

2005～2006年国外塑料工业进展

收集了2005年7月～2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂（聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂）、工程塑料（聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚）、通用热固性树脂（酚醛、聚氨酯、不饱和树脂、环氧树脂）、特种工程塑料（聚苯硫醚、液晶聚合物、聚醚醚酮）的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。