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纳米载体固定化酶的最新研究进展 总被引:1,自引:0,他引:1
催化剂是化学工业的重要基础,其中酶是重要的高效天然催化剂。近年来,酶被越来越多地应用于工业领域,如精细化工、食品工业、制药工业、纺织业和制浆造纸。然而,由于游离酶存在价格昂贵及操作稳定性(特别是回收与重复使用性能)低等缺点,其在工业上的进一步应用受到一定限制。对酶进行固定化是解决上述问题的有效途径。一个理想的酶固定化技术需要载体具有良好的生物相容性和高比表面积,能够负载适量的酶并且具有很好的重复使用性能,固定化酶的过程简单温和,所得到的固定化酶制剂具有良好的催化性能、稳定性以及工业应用价值。尽管固定化酶技术经过了多年的发展,但仍需进一步研究。近几年,人们研究了基于纤维素纳米晶类、聚多巴胺类纳米载体以及生物相容性合成有机物纳米胶等新型载体对酶的固定化,取得了较好的成果。本文综述了这些新型纳米载体的制备以及酶的固定化过程,阐述了纳米载体固定化酶的结构和催化性能,并展望了发展前景。纤维素是全球产量最高、来源最广的生物聚合物。纤维素经过一定的酸(常用硫酸和盐酸)水解处理后,剩下的是具有高结晶度的纤维素纳米晶。它具有高比表面积、高机械强度和高长径比等优异性能。因此,研究者利用纤维素纳米晶作为载体进行酶固定化,获得了高负载量、高催化性能的固定化酶制剂。基于仿生矿化法制备的聚多巴胺类材料近年来获得研究者越来越多的关注。多巴胺具有良好的自聚合能力,可以对无机、有机等各种材料进行表面修饰。同时,聚多巴胺中含有的活性官能团可以与酶发生交联,从而达到固定化酶的效果。基于合成性聚合物纳米胶载体的固定化酶技术同样是一个新兴的、有意义的研究领域。相关的固定化过程可分为两大类:(1)在酶分子表面通过原位聚合生成纳米胶(growing-from过程);(2)将酶与预先合成的纳米胶进行交联(grafting-to过程)。其中, growing-from过程是先将酶分子丙烯酰化,再进行原位聚合。而原位聚合又可分为自由基聚合、原子转移自由基聚合(ATRP)和可逆加成-断裂链转移聚合(RAFT)。其中, ATRP和 RAFT主要用于制备环境响应型的酶-聚合物纳米凝胶。 相似文献
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《催化学报》2016,(11)
催化剂是化学工业的重要基础,其中酶是重要的高效天然催化剂.近年来,酶被越来越多地应用于工业领域,如精细化工、食品工业、制药工业、纺织业和制浆造纸.然而,由于游离酶存在价格昂贵及操作稳定性(特别是回收与重复使用性能)低等缺点,其在工业上的进一步应用受到一定限制.对酶进行固定化是解决上述问题的有效途径.一个理想的酶固定化技术需要载体具有良好的生物相容性和高比表面积,能够负载适量的酶并且具有很好的重复使用性能,固定化酶的过程简单温和,所得到的固定化酶制剂具有良好的催化性能、稳定性以及工业应用价值.尽管固定化酶技术经过了多年的发展,但仍需进一步研究.近几年,人们研究了基于纤维素纳米晶类、聚多巴胺类纳米载体以及生物相容性合成有机物纳米胶等新型载体对酶的固定化,取得了较好的成果.本文综述了这些新型纳米载体的制备以及酶的固定化过程,阐述了纳米载体固定化酶的结构和催化性能,并展望了发展前景.纤维素是全球产量最高、来源最广的生物聚合物.纤维素经过一定的酸(常用硫酸和盐酸)水解处理后,剩下的是具有高结晶度的纤维素纳米晶.它具有高比表面积、高机械强度和高长径比等优异性能.因此,研究者利用纤维素纳米晶作为载体进行酶固定化,获得了高负载量、高催化性能的固定化酶制剂.基于仿生矿化法制备的聚多巴胺类材料近年来获得研究者越来越多的关注.多巴胺具有良好的自聚合能力,可以对无机、有机等各种材料进行表面修饰.同时,聚多巴胺中含有的活性官能团可以与酶发生交联,从而达到固定化酶的效果.基于合成性聚合物纳米胶载体的固定化酶技术同样是一个新兴的、有意义的研究领域.相关的固定化过程可分为两大类:(1)在酶分子表面通过原位聚合生成纳米胶(growing-from过程);(2)将酶与预先合成的纳米胶进行交联(grafting-to过程).其中,growing-from过程是先将酶分子丙烯酰化,再进行原位聚合.而原位聚合又可分为自由基聚合、原子转移自由基聚合(ATRP)和可逆加成-断裂链转移聚合(RAFT).其中,ATRP和RAFT主要用于制备环境响应型的酶-聚合物纳米凝胶. 相似文献
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本研究以期研制出能重复使用的固定化乙酰胆碱酯酶(AChE),为天然产物复杂体系中AchE抑制剂筛选新方法的发展奠定基础.以氨基化硅胶(APS-Si)微球为载体,戊二醛为交联剂对乙酰胆碱酯酶进行交联固定化,并研究了酶的最佳固定化条件和固定化酶的性质.结果表明,0.05 g氨基化硅胶微球载体,用戊二醛溶液活化6 h后,在给酶量5 U,28℃固定16 h条件下,得到固定化酶的活性最大.固定化酶在常温(20~40℃),以及较宽pH范围内(pH 6~10)均具有较高的活性,并且具有良好的保存稳定性和可重复利用率,为基于固定化靶酶亲和-色谱质谱联用分析快速筛选乙酰胆碱酯酶抑制剂新方法的发展奠定了基础. 相似文献
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1 引 言固定化L 天门冬酰胺酶的研究长期以来倍受人们的关注。共价法是一种常用的方法 ,该方法通过载体与酶之间形成共价键而将酶固定于载体上 ,这样可防止酶的脱落 ,故而起到了催化作用。对固定化L 天门冬酰胺酶进行活性定位的研究 ,将有助于L 天门冬酰胺酶的固定化 ,其活性定位的基本原理如下 :底物 酶 产物 +捕捉剂 (金属离子 )活性部位沉淀利用聚焦电子束对固定化酶表面进行激发 ,有活性的部位发射出沉淀金属的特征X 射线 ,利用X 射线能谱分析即可定位酶的活性部位。本文利用MgCl2 作为捕捉剂 ,以L 天门冬酰胺为底物 ,经固定化L… 相似文献
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《Journal of membrane science》1999,152(2):235-240
Ultrafiltration membrane has been prepared from the copolymer of acrylonitrile–glycidylmethacrylate and the porosity of the membrane was studied. The asymmetric structure was proved by scanning electron microscopy. The basic characteristics of the membrane were measured – water permeability, water content, membrane selectivity, etc. The membrane obtained was used as a carrier for immobilization of glucose oxidase. The immobilization was carried out covalently by two methods: direct bonding of the enzyme and indirectly by a spacer (hexamethylenediamine) and cross-linking agent (glutar aldehyde). The amount of bound protein and relative activity of the immobilized glucose oxidase were determined. Temperature optimum, pH optimum and storage stability of the immobilized glucose oxidase were determined. It was proved that glucose oxidase immobilized by the direct method shows better characteristics compared with the indirect method. 相似文献
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Yubin Ge Hui Zhou Wei Kong Yi Tong Shuyan Wang Wei Li 《Applied biochemistry and biotechnology》1998,69(1):17-29
Bilayer glucose isomerase was immobilized in porousp-trimethylaminepolystyrene (TMPS) beads through a molecular deposition technique. Some of the factors that influence the activity
of immobilized glucose isomerase were optimized, with the enzyme concentration of 308 IU/mL, enzyme-to-matrix ratio of 924
IU/g wet carrier, and hexamethylene bis(trimethylammonium iodine) concentration of 15 mg/mL giving the maximum catalytic activity
(2238 IU/g dry gel) of the immobilized bilayer glucose isomerase, retaining 68.5% of the initially added activity. The half-life
of the immobilized bilayer glucose isomerase was approx 45 d at pH 8.5, 60°C, with 50% (w/v) glucose as substrate. The specific
productivity of the immobilized bilayer glucose isomerase was 223 g dry D-glucose/g dry immobilized enzyme per d. 相似文献
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Yubin Ge Hui Zhou Wei Kong Yi Tong Shuyan Wang Wei Li 《Applied biochemistry and biotechnology》1998,69(3):203-215
Bilayer glucose isomerase was immobilized in porousp-trimethylamine-polystyrene (TMPS) beads, through a molecular deposition technique. Some of the factors that influence the
activity of immobilized glucose isomerase were optimized, with the enzyme concentration of 308 IU/mL, enzyme:matrix ratio
of 924 IU/g wet carrier, and hexamethylenebis(trimethylammonium iodine) concentration of 15 mg/mL, giving the maximum catalytic activity (2238 IU/g dry gel) of the immobilized
bilayer glucose isomerase, retaining 68.5% of the initially added activity. The half-life of the immobilized bilayer glucose
isomerase was approx 45 d at pH 8.5, 60°C, with 50% (w/v) glucose as substrate. The specific productivity of the immobilized
bilayer glucose isomerase was 223 g dry D-glucose/g dry immobilized enzyme per day. 相似文献
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A unique polymer matrix that is suitable for immobilizing growing cells has been developed. Alginate was chemically modified
with polyethyleneimine (PEI), and the resultant polymer aggregate was evaluated as a cell carrier. Our method of immobilization
depends on reversible gelation of the PEI-modified alginate. Our hypothesis is that immobilized cells grow by dissolving the
surrounding gel matrix; the dissolved polymer adduct is displaced peripherally and gelled again by the influx of calcium ion
from the surrounding fermentation broth, retaining both cells and carrier polymer in the gel beads. Thus, the immobilized
cells gain space for growth by expanding the carrier matrix. The PEI modification offers the following advantages: (1) improved
mechanical strength; (2) improved cell retention; (3) increased catalyst life; (4) ease of pelletization; and (5) an apparent
bacteriostatic capability.
When immobilized yeast cells were applied to a continuous ethanol fermentation, 94% theoretical conversion of glucose to ethanol
was observed, with a reactor productivity of 15–30 g/L/h in a nonsterile reactor. A 3-mo catalyst life and minimal cell washout
were observed. 相似文献
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Liposome chromatography: liposomes immobilized in gel beads as a stationary phase for aqueous column chromatography 总被引:1,自引:0,他引:1
Liposomes have been used as a stationary phase for column chromatography with an aqueous mobile phase. They were immobilized in the pores of carrier gel beads by two methods: (A) hydrophobic ligands were coupled to the matrix of gel beads, which then were packed into a column and liposomes were applied and became associated with the ligands by hydrophobic interaction; and (B) phospholipids and detergent were dialysed in the presence of gel beads; many of the liposomes that formed in the pores of the beads were sterically immobilized by the gel matrix. Proteoliposomes containing red cell glucose transport protein in the lipid bilayers were immobilized in a column by method A. This column retained D-glucose longer than L-glucose. In contrast to L-glucose, D-glucose was transported into and out of the immobilized liposomes, causing an increased retention. Liposomes with (stearylamine)+ or (phosphatidylserine)- in their lipid bilayers were immobilized by method B and the gel beads were packed into a column. A protein of opposite charge was applied in excess. Under suitable conditions, the protein molecules became close-packed on the liposome surfaces. Ion-exchange chromatographic experiments with proteins showed that these sterically immobilized liposomes were also stable enough to be used as a stationary phase. The loss of lipids was 5-23% in the first run at high protein load and with sodium chloride gradient elution but was lower in subsequent runs. It is proposed that water-soluble molecules can be separated and their interactions with liposome surfaces studied by chromatography on immobilized liposomes in detergent-free aqueous solution. Membrane proteins can be inserted and ligands can be anchored in the lipid bilayers for chromatographic purposes. 相似文献
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A flow-injection conductometric manifold equipped with an immobilized glucose-oxidase mini-reactor was proposed for the determination of glucose concentration. The glucose of the injected sample plug was oxidized enzymatically to its δ-lactone, and the hydrolysis of the lactone generated a concentration-dependent flow-injection signal. The dynamic range was from the tens of μM to the mM order of glucose; the immobilized enzyme reactor was stable for at least several months. The pH of the carrier solution was maintained in a slightly alkaline region (ca. 8.0 by 500 μM of Tris-HCl) to accelerate the spontaneous hydrolysis of δ-gluconolactone. The repeatability of the flow-injection signals was improved (CV < 3%, n = 7) by the addition of Triton X-100® (0.7% w/v) into the carrier solution. 相似文献
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A chemiluminescence (CL) biosensor on a chip coupled to microfluidic system is described in this paper. The CL biosensor measured 25×45×5 mm in dimension, was readily produced in analytical laboratory. Glucose oxidase (GOD) was immobilized onto controlled-pore glass (CPG) via glutaraldehyde activation and packed into a reservoir. The analytical reagents, including luminol and ferricyanide, were electrostatically co-immobilized on an anion-exchange resin. The most characteristic of the biosensor was to introduce the air as the carrier flow in stead of the common solution carrier for the first. The glucose was sensed by the CL reaction between hydrogen peroxide produced from the enzymatic reaction and CL reagents, which were released from the anion-exchange resin. The proposed method has been successfully applied to the determination of glucose in human serum. The linear range of the glucose concentration was 1.1-110 mM and the detection limit was 0.1 mM (3σ). 相似文献
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Yan Liu Rui Lv Shiyong Sun Daoyong Tan Faqin Dong Yevgeny A.Golubev Xiaoqin Nie Olga B.Kotova Jin Liu Ke Wang 《中国化学快报》2022,33(2):807-811
Various enzymatic reactions or enzymatic cascade reactions occur efficiently in biological microsystems due to space constraints or orderly transfer of intermediate products. Inspired by this, the horseradish peroxidase(HRP)-like nanozyme(Fe-aminoclay) was in situ synthesized on the surface of alkali-activated halloysite nanotubes and the natural enzyme(glucose oxidase, GOx) was immobilized on it to construct a high-efficiency GOx-Fe AC@AHNTs cascade nanoreactor. In which, Fe AC@AHNTs can not on... 相似文献
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This study is concerned with chitosan-polyacrylic acid complex as a carrier to immobilize glucose oxidase (GOD)and cellulase. The optimum emperature of the immobilized GOD (IG) was determined to be 60℃which is higher than that of the native GOD about 40℃. The optimum temperature of the immobilized cellulase (IC) was determined to be about 30℃higher than that of native cellulase. Both of the optimum pH of IG and IC shifted one pH unit to acid. Immobilized enzyme may be used in more wide pH range. Their storage life are much longer compared with their native states. Both of them can be reused at least 12 times. 相似文献