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聚乙烯吡咯啉酮—盐—水液—固萃取体系分离纯化α—淀粉酶的研究 总被引:2,自引:0,他引:2
本文研究了α-淀粉酶,酪蛋白、牛血清白蛋白在聚乙烯吡咯啉酮-盐-水液-固萃取体系中的萃取行为,着重讨论了PH值、(NH4)2SO4浓度及激活剂NaCl对酶萃取订的影响。 相似文献
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吴芳华 《分析测试技术与仪器》2012,18(2):114-120
固相萃取技术是一种用于样品分离、纯化、浓缩的重要的样品前处理手段。近年来,高分子材料合成技术、分子印迹技术等新技术与传统固相萃取技术相结合,衍生出众多技术改进和创新。主要对各种固相萃取新技术进行评述。 相似文献
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碱性条件下的聚合物-盐水-液-固萃取体系应用于钴、锌、镍的分离和测定 总被引:3,自引:0,他引:3
1 引 言水溶性高聚物的水溶液在无机盐的存在下能分成液 固两相 ,称为聚合物 盐水 液 固萃取体系。是近 10年开发的新型萃取体系。该体系在酸性条件下已成功地用于金属离子的定量萃取分离和分离纯化生物活性物质。已报道的聚合物 盐水 液 固萃取体系都是在酸性条件下 ,用调整聚合物和盐的浓度 ,使其分相并进行分离金属离子的。在碱性条件下的研究从未报道。这两种条件的区别在于 ,分相盐浓度与吐温浓度在碱性条件明显低于酸性条件 ,特别是分相用盐更低 ,降低了盐效应。例如 ,使Co 萃取率E %达 10 0 %时 ,在pH 3.2 0~ 7.0 … 相似文献
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双酚A分子印迹聚合物为萃取介质搅拌饼固相萃取的制备及其萃取性能研究 总被引:2,自引:0,他引:2
以双酚A为模板,4-乙烯基吡啶为单体,利用整体材料"原位"聚合技术制备分子印迹聚合物为基质的萃取饼,并与利用一次性注射器空管加工而成的萃取器相结合,建立了分子印迹搅拌饼固相萃取(MIP-SCSE)技术。考察了制备条件对MIP-SCSE选择吸附性能的影响。在此基础上,与高效液相色谱-二极管阵列检测器联用,探讨MIP-SCSE对环境水样中双酚A及其它酚类物质的选择萃取性能,考察萃取过程中基底离子强度、pH值以及吸附与解吸时间等萃取条件对萃取性能的影响。结果表明;在最佳萃取条件下,MIP-SCSE对模板分子及其它酚类物质具有一定选择性能和较高的富集能力,对双酚A的线性范围为1.0~200μg/L;检出限LOD(S/N=3)为0.67μg/L;定量限LOQ(S/N=10)为2.24μg/L。在实际水样分析中,模板分子加标回收率为86.2%~112.2%。在MIP-SCSE使用过程中,萃取饼不与容器壁接触,因此具有优良的使用寿命,至少可连续使用600 h。 相似文献
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在乙醇溶液中,以Cu(Ⅱ)为模板分子,二甲基丙烯酸乙二醇酯为交联剂采用分散聚合法制备铜离子印迹聚合物(Cu~(2+)-IIP),并通过傅里叶变换红外光谱、紫外光谱对聚合物的结构及性能进行了表征。考察了吸附时间、溶液初始浓度、pH值等因素对聚合物吸附性能的影响。实验表明,室温条件下,在pH=6,90min吸附达到平衡,其最大吸附量为1.42mmol/g;与非印迹聚合物相比,印迹聚合物有较大的吸附量及较好的选择性。因此,印迹聚合物在固相萃取、水处理等方面具有很好的应用前景。 相似文献
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Davidenko I. I. Davidenko N. A. Savchenko I. A. 《Theoretical and Experimental Chemistry》2004,40(2):105-109
The characteristics of the dark current and photocurrent of samples with sandwich structures with films of macromolecular chelates based on 7-octen-2,4-dionatocobalt. The electro- and photoconductivities increase somewhat with an increase in temperature over the 290-370 K range with small electrical field intensity, but they decrease in large electric fields. A change in the nature of the conductivity from semiconductor to metallic was observed with increase in electric field. It is proposed that the number of cobalt ions, through which electron transfer occurs, changes with changes in the electrical field or the temperature. 相似文献
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Liquid-liquid Extraction System Based on Non-ionic Surfactant-salt-H_2O and Mechanism of Drug Extraction 总被引:1,自引:0,他引:1
Lei LI Feng LIU* Xiang Xu KONG Shun SU Ke An LI College of Chemistry Molecular Engineering Peking University Beijing Department of Chemistry Gannan Teachers College Ganzhou 《中国化学快报》2002,13(4)
The utilization of solid-liquid extraction system based on polymer-(NH4)2SO4 -H2O on separation of metal ions and bio-active substances has been summarized1. Cloud point extraction (CPE) benefits the environment and has been used in separation of metal chelates, biomacromolecules and in pretreatment of environmental samples2-4. In a 10 mL color comparison tube 20% PEG-1000 and 2.5 g (NH4)2SO4 were chosen as phase separation condition at pH 5.5. The average extraction efficiencies we… 相似文献
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《Analytical letters》2012,45(10):1818-1831
Abstract A powerful sample cleanup procedure using molecularly imprinted polymer as a solid phase extraction material for the preconcentration of piroxicam in pharmaceutical samples has been developed. The optimized conditions for the preparation of molecularly imprinted polymer as a selective sorbent for the preconcentration of this drug were also studied. It is very important to note that a preconcentration factor of 1000 and retention capacity of 30.0 mg/g can be achieved. Recoveries up to 95% were accomplished for the analyte of interest from a pharmaceutical piroxicam capsule sample. All of these experiments were also performed with nonimprinted polymer. 相似文献
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《Analytical letters》2012,45(5):793-808
ABSTRACT A new biomimetic bulk acoustic wave (BAW) sensor based on a molecularly imprinted polymer (MIP) was fabricated and applied for the determination of phenobarbital The MIP was synthesized using phenobarbital as the template molecule and methacrylic acid as the functional monomer by the non-covalent method. In absolute ethanol, the sensor exhibited good selectivity and sensitivity. A linear relationship between 9.0×10?8 M and 5.0×10?5 M was revealed. The determination limit was 5.0×10?8 M. In harsh chemical environments such as high temperature, organic solvent, bases, acids, etc., the sensor still exhibited long-time stability. Satisfactory results of real sample assay were obtained by the proposed method. 相似文献