Investigation of Three-liquid-phase Extraction Systems for Simultaneous Separation of Emodin and Rhein

Several three-liquid-phase extraction systems comprised of organic extractant,polymer and salt aqueous solution were applied to isolate and purify simulated herbal extract containing emodin and rhein.Some influential factors on the partitioning behaviors were studied.The results revealed that extractant type and solution pH value were crucial factors for improving the separation performance.The optimal separation results were obtained at pH 8.00 with methyl isobutyl ketone as the extractant,10%（ω） polyethylene glycol with the molecular weight 4000 Da,and 10%（ω） ammonium sulphate.Under the optimized conditions,95%emodin and 97%rhein were simultaneously extracted into the organic phase and polymer-rich phase from simulated herbal solution with the initial concentration of 100×l0^-6（ω）,respectively,and their separation factor of over 10000 was achieved.By adjusting pH value,back extraction rate of both emodin and rhein could be up to about 99%.With the assistance of molecular simulation program XLOGP3 and molecular orbital package,the possible mechanism of extraction was analyzed,and hydrophobic interaction and hydrogen-bonding interaction might be the major driving forces affecting the partitioning behaviors of emodin and rhein.     

氨基功能化超顺磁性PGMA高分子微球去除废水中的铬(Ⅵ)

通过渗透沉积过程合成单分散的磁性聚甲基丙烯酸缩水甘油酯(PGMA-NH2)高分子微球,对其进行了SEM,FT-IR,XRD表征.并着重研究了磁性PGMA-NH2高分子微球对Cr(Ⅵ)的吸附性能及吸附机理.结果表明,此磁性高分子微球对Cr(Ⅵ)有较高的吸附量,等温吸附数据符合Langmuir模型,在温度298.15 K,...     

铈盐引发高吸附量氨基化PGMA高分子微球合成及去除废水中Cr(VI)(英文)

A novel polyglycidylmethacrylate(PGMA) microspheres with high adsorption capacity of Cr(VI) was prepared by cerium(IV) initiated graft polymerization of tentacle-type polymer chains with amino group on polymer microspheres with hydroxyl groups.The micron-sized PGMA microspheres were prepared by a dispersion polym-erization method and subsequently modified by ring-opening reaction to introduce functional hydroxyl groups.The polymer microspheres were characterized by scanning electron microscopy(SEM) and Fourier transform infrared spectroscopy(FTIR).The results indicated that the polymer microspheres had an average diameter of 5 μm with uniform size distribution.The free amino group content was determined to be 5.13 mmol?g?1 for g-PGMA-NH2 mi-crospheres by potentiometric and conductometric titration methods.The Cr(VI) adsorption results indicated that the graft polymerization of tentacle-type polymer chains on the polymer microspheres could produce adsorbents with high adsorption capacity(500 mg?g?1).The polymer microspheres with grafted tentacle polymer chains have poten-tial application in large-scale removal of Cr(VI) in aqueous solution.     

咪唑和吡啶离子液体对青霉素酰化酶催化性能的影响

采用两步法合成并表征了阳离子不同的咪唑型和吡啶型离子液体[C4mim]BF4,[C7mim]BF4,[C4pyr]BF4和[C7pyr]BF4,并将其应用于固定化青霉素G酰化酶(ImPGA)催化分解青霉素G钾盐的反应,考察了阳离子对酶活性、稳定性、动力学的影响,及ImPGA在不同离子液体中酶活性受底物(青霉素G钾盐)抑制情况.结果表明,ImPGA在[C7pyr]BF4,[C4pyr]BF4和[C7mim]BF4中活性依次降低,在亲水性较强的[C4mim]BF4中易失去活性,其在3种离子液体中37℃下保存30min活性没有降低,米氏常数Km依次为752.15,160.57和62.74mmol/L,最大反应速率Vmax依次为0.204,0.042和0.024mmol/(g·min);底物浓度为26.85～295.32mmol/L时酶活性不受底物抑制.     

氨基功能化超顺磁性PGMA高分子微球去除废水中的铬(Ⅵ)

通过渗透沉积过程合成单分散的磁性聚甲基丙烯酸缩水甘油酯(PGMA-NH2)高分子微球,对其进行了SEM,FT-IR,XRD表征.并着重研究了磁性PGMA-NH2高分子微球对Cr(Ⅵ)的吸附性能及吸附机理.结果表明,此磁性高分子微球对Cr(Ⅵ)有较高的吸附量,等温吸附数据符合Langmuir模型,在温度298.15K,pH=4.5时,吸附剂的饱和吸附容量为263.16mg/g.吸附量与废水中Cr(Ⅵ)的离子形式有关,pH=1.5时吸附效果最好,在15min内达到平衡.吸附以离子交换与静电引力为主,自发进行,焓变ΔH0=9.63kJ/mol.     

Pluronic嵌段共聚物磁性纳米颗粒的制备及其对漆酶的分离纯化

选择合适的双亲性嵌段共聚物Pluronic产品接枝到Fe3O4粒子的表面,合成了粒径均一、亲水性好、非特异性吸附低的纳米级磁性分离载体(PMNPs). 通过对漆酶发酵液的分离纯化研究了Pluronic对排除蛋白非特异性吸附的作用. 结果表明,PMNPs对漆酶的最大吸附量可达0.535 mg/mg,在5~40℃内基本不受温度变化影响,对漆酶发酵液的分离纯化因子为3.4,酶活收率达62.9%,可实现一步分离提纯.     

磁载体MoS2催化剂制备及其重油减黏

以SiO₂/Fe₃O₄为载体，MoS₂为活性组分，通过水热法制备出超顺磁性MoS₂/SiO₂/Fe₃O₄催化剂，并对催化剂进行XRD、VSM、BET、FTIR等表征。结果表明：催化剂有效担载活性组分并且具有优异的磁学性能，SiO₂包覆不仅能保护磁核，而且显著增大催化剂的比表面积。以常压渣油为原料，系统考察了催化剂的减黏性能。发现所制备的磁载体催化剂减黏效果高于商业二硫化钼及羰基钼，提升反应温度能达到更好的减黏效果。此外，在外加磁铁的作用下，催化剂可以方便回收以达到再利用的效果。将具有优异磁学性能的纳米粒子与具有催化性能的活性组分相结合制备的磁性纳米催化剂，为开发重油改质催化剂提供了新的思路。     

核酸适配体在生化分离及检测领域中的研究进展

核酸适配体是一种能够特异性地识别目标物的寡聚核苷酸,可以是RNA也可以是DNA。较其他识别分子而言,适配体具有性质稳定、易合成、易标记、分子量较小和目标分子广泛等优势。目前核酸适配体主要被应用在检测、分离纯化和医疗三大领域,本文主要论述了适配体在生化分离及检测领域中的研究进展。     

超顺磁性聚醋酸乙烯酯微球亲和分离纳豆激酶

采用改进悬浮聚合法制备了磁性聚醋酸乙烯酯微球,经水解、氨基化修饰,以戊二醛作间隔臂偶联配基对氨基苯甲脒,制得磁性PVA亲和微球,用于纳豆激酶粗酶液的分离纯化,对所制微球进行了表征,研究了纳豆激酶的吸附平衡、吸附和解吸动力学、酶的纯度和酶活回收. 结果表明,磁性微球具有较高的比饱和磁化强度(32.4 emu/g),40 min即可达到纳豆激酶的吸附平衡,15 min内完成酶的解吸,酶活回收率接近75%,纯化因子为10.3,酶的分子量为28 kDa,电泳分析为一条带.     

聚苯乙烯微球固定化的Pd卟啉:高效可重复利用的Heck反应催化剂

以苯乙烯,1,4-二氯甲氧基丁烷,5,10,15,20-四（4-羟苯基）卟啉（MTP）为原料制取了聚苯乙烯/Pd卟啉（PS/Pd-MTP）Heck反应催化剂。利用FT-IR,ICP等手段对其进行了表征。在100℃,N₂氛围下,将0.1 mol%PS/Pd-MTP用于4-碘硝基苯和丙烯酸乙酯的Heck反应体系。结果表明:负载型PS/Pd-MTP的催化活性（97.5%）远优于游离的Pd卟啉（Pd-MTP）（55.2%）:将负载型PS/Pd-MTP在4-碘硝基苯与丙烯酸乙酯的Heck反应体系10次,其催化活性未见降低。