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1.
球形纤维素固定化DNA制备免疫吸附剂   总被引:15,自引:0,他引:15  
以球形纤维素为载体,经环氧氯丙烷活化后共价键联小牛胸腺DNA,制备DNA免疫吸附剂,通过血液灌流能够治疗系统性红斑狼疮.对病人血清的吸附实验结果表明,每毫升吸附剂与3mL病人血清混合,于37℃保温1 h,可吸附除去40%~70%致病抗体  相似文献   

2.
扩张床吸附基质研究进展   总被引:7,自引:0,他引:7  
针对扩张床吸附这一新型蛋白质分离纯化技术,论述了吸附剂基质对该项技术应用的重要性,并且评述了近十年来扩张床吸附基质的研究状况,在此基础上重点介绍了基质所需的特性、常用的扩张床基质及其制备方法。  相似文献   

3.
基于吸附制冷的实际运行工况,本文设计搭建了一种新型的测试整体成型吸附剂性能装置;通过吸附床温度变化特性测试及吸附剂性能测试实验,确定了该装置用于吸附剂性能测试实验的可行性及可靠性。吸附床温度变化特性测试表明,该装置可以在有效控制整体成型吸附剂吸附脱附温度情况下,完成吸附剂在吸附和脱附循环过程中的性能测试;吸附剂性能测试实验表明,经活化后的13X沸石分子筛对吸附质-水的最大吸附量为0.196g/g,单位质量最大吸附速率为1.79×10~(-3)g/(g·min),冷凝/蒸发器的最低蒸发温度为12℃,平均冷凝温度为27℃;测试得到的13X沸石分子筛对水的吸附量与参考文献中该值的平均偏差仅为5.206%,因此,本实验装置用于整体成型以及堆积状态下的吸附剂性能测试具有可行性及可靠性;利用该系统可以为吸附制冷提供吸附剂性能的基础实验数据。  相似文献   

4.
吸附与生物技术的耦合是实现燃料油品清洁生产的新发展方向,提出了一种吸附剂生物再生循环使用的新耦合方法,首先用吸附剂吸附脱除油品中的含硫化合物,然后用微生物脱附吸附剂表面吸附的硫化物,实现吸附剂再生.利用Y型分子筛通过离子交换再用He保护自动还原的方法制备了π络合吸附剂吸附Cu(I)-Y,以DBT为模型化合物考察了吸附剂的吸附性能.以选择性脱硫菌德氏假单胞菌(Pseudomonasdelafieldii)R-8为生物催化剂,考察了细胞浓度、油相体积、水相/吸附剂比对吸附剂脱附率的影响.加入油相可以大大提高DBT脱附量和生成2-HBP的量.增加水相中脱硫菌R-8的浓度、增大水相/吸附剂比,可以实现DBT脱附,促进DBT转化为2-HBP.在水相脱硫菌株R-8浓度为75g·L?1、水相/吸附剂比为300mL/g、油相/水相比1/3(V/V)的条件下,脱附的DBT在6h内转化率达到89%,24h内转化率为100%.生成2-HBP的量主要由吸附剂吸附硫化物的量、水相中微生物细胞的浓度、油相/水相体积比、水相/吸附剂比决定.吸附剂经过正辛烷洗涤、100℃下干燥24h、He保护450℃还原活化3h,再生吸附剂的吸附能力为新鲜吸附剂的95%.  相似文献   

5.
吸附与生物技术的耦合是实现燃料油品清洁生产的新发展方向, 提出了一种吸附剂生物再生循环使用的新耦合方法, 首先用吸附剂吸附脱除油品中的含硫化合物, 然后用微生物脱附吸附剂表面吸附的硫化物, 实现吸附剂再生. 利用Y型分子筛通过离子交换再用He保护自动还原的方法制备了(络合吸附剂吸附Cu(Ⅰ)-Y, 以DBT为模型化合物考察了吸附剂的吸附性能. 以选择性脱硫菌德氏假单胞菌(Pseudomonas delafieldii)R-8为生物催化剂, 考察了细胞浓度、油相体积、水相/吸附剂比对吸附剂脱附率的影响. 加入油相可以大大提高DBT脱附量和生成2-HBP的量. 增加水相中脱硫菌R-8的浓度、增大水相/吸附剂比, 可以实现DBT脱附, 促进DBT转化为2-HBP. 在水相脱硫菌株R-8浓度为75 g·L-1、水相/吸附剂比为300 mL/g、油相/水相比1/3(V/V)的条件下, 脱附的DBT在6 h内转化率达到89%, 24 h内转化率为100%. 生成2-HBP的量主要由吸附剂吸附硫化物的量、水相中微生物细胞的浓度、油相/水相体积比、水相/吸附剂比决定. 吸附剂经过正辛烷洗涤、100℃下干燥24 h、He保护450℃还原活化3 h, 再生吸附剂的吸附能力为新鲜吸附剂的95%.  相似文献   

6.
扩张床吸附技术   总被引:7,自引:0,他引:7  
扩张床是流化床的一种特例。它具有流化床的特点,能处理含悬浮颗粒的液体。又具有固定床的优点,流动成活塞流;返混程度低,分离效率高。作为蛋白质的初步分离方法,它能取代固液分离、浓缩和初步纯化等三步操作。具有提高收率、降低投资费用、缩短操作时间等优点,成为生物工程下游过程的研究热点。本文综述了近年来扩张床吸附技术的发展。包括:1、原理:床层的分层稳定性、吸附剂和吸附柱;2、操作:吸附、洗涤、洗脱和再生4个步骤;3、流动动力学特性:床层扩展特征和停留时间分布;4.在蛋白质纯化中的应用。  相似文献   

7.
本文以城市污水处理厂的剩余污泥及膨润土为原料制备颗粒吸附剂。通过振荡吸附实验,考察了城市污泥-膨润土颗粒吸附剂的制备方法及颗粒吸附剂在含Pb2+废水中的吸附特性。结果表明:当膨润土和城市污泥的质量比为4:6、颗粒粒径为1.2mm、焙烧温度为550℃、焙烧时间为2h时,吸附剂的比表面积可达20.17m2/g,对废水中的Pb2+的吸附效率可达92%以上。  相似文献   

8.
吸附与生物技术的耦合是实现燃料油品清洁生产的新发展方向, 提出了一种吸附剂生物再生循环使用的新耦合方法, 首先用吸附剂吸附脱除油品中的含硫化合物, 然后用微生物脱附吸附剂表面吸附的硫化物, 实现吸附剂再生. 利用Y型分子筛通过离子交换再用He保护自动还原的方法制备了π络合吸附剂吸附Cu(I)-Y, 以DBT为模型化合物考察了吸附剂的吸附性能. 以选择性脱硫菌德氏假单胞菌(Pseudomonas delafieldii)R-8为生物催化剂, 考察了细胞浓度、油相体积、水相/吸附剂比对吸附剂脱附率的影响. 加入油相可以大大提高DBT脱附量和生成2-HBP的量. 增加水相中脱硫菌R-8的浓度、增大水相/吸附剂比, 可以实现DBT脱附, 促进DBT转化为2-HBP. 在水相脱硫菌株R-8浓度为75 g·L-1、水相/吸附剂比为300 mL/g、油相/水相比1/3(V/V)的条件下, 脱附的DBT在6 h内转化率达到89%, 24 h内转化率为100%. 生成2-HBP的量主要由吸附剂吸附硫化物的量、水相中微生物细胞的浓度、油相/水相体积比、水相/吸附剂比决定. 吸附剂经过正辛烷洗涤、100℃下干燥24 h、He保护450℃还原活化3 h, 再生吸附剂的吸附能力为新鲜吸附剂的95%.  相似文献   

9.
以木屑为原料,在低温条件下一步法制得活性炭基吸附剂,考察了吸附剂制备条件和液-固、气-固吸附条件对吸附剂脱硫性能的影响。结果表明,吸附剂的最佳制备条件为,浸渍液与木屑质量比为1:1,浸渍液中硝酸质量分率为30%、吸附剂表面NiO负载量为5%,常温下浸渍24 h,400℃焙烧3 h。该吸附剂在0.2 g吸附剂/10 mL模拟油、温度为40℃及时间为5 h的液-固吸附脱硫的条件下,脱硫率为28.36%,吸附四次后饱和吸附硫容量可达2.34 mgS/g;在气-固吸附温度为250℃、空速为6.3 h-1的条件下,饱和吸附硫容量为2.37 mgS/g;高温气-固吸附脱硫对吸附剂的影响表明,与脱硫前相比,吸附剂在比表面积、总孔体积、微孔体积均有明显提高,这说明气-固吸附脱硫过程同时实现了活性炭的扩孔活化。甲苯溶剂再生实验表明,经五次再生后吸附剂的再生性能均可达90%以上。  相似文献   

10.
研究了以火棉胶作为包埋材料将DNA配基固定于碳化树脂表面制备的类风湿关节炎免疫吸附剂的吸附性能,静态吸附条件下,当ssDNA的固定量在0.4mg/mL树脂时吸附性能最佳,对3种类风湿因子(RF)的最佳饱和吸附量分别为IgMRF:2458IU/mL、IgGRF:2877IU/mL、IgARF:1100IU/mL.吸附120分钟后达到吸附平衡,对血浆中白蛋白及总蛋白的清除率分别低于8%和6%,表现出较好的吸附选择性.吸附剂经毒理实验证明,使用安全性较高.对活犬进行体外血液灌流实验表明该吸附剂具有良好的血液相容性.  相似文献   

11.
The specially prepared adsorbent is most important in realizing the expanded bed adsorption (EBA) process. In the present work, a novel poly glycidyl methacrylete–zirconium dioxide–β-cyclodextrin (PGMA–ZrO2–β-CD) composite matrix for EBA has been first prepared. Wet density, water content and pore properties of the composite beads have been investigated, which shows good expansion and stability in EBA. The application of custom-made adsorbent has been investigated to recover isoflavones from soy molasses. The recovery is up to 90% and the purity of isoflavones obtained is 75.4%. Compared with the traditional purification processes, EBA has the advantage of high efficiency and integrality, which leads to large reduction in operation time and cost.  相似文献   

12.
Three techniques (liquid–liquid extraction, packed bed adsorption and expanded bed adsorption) have been compared for the purification of flavonoids from the leaves of Ginkgo biloba L. A crude Ginkgo extract was obtained by refluxing with ethanol for 3 h. The yield of flavonoids achieved by this crude extraction was about 19% (w/w) and the purity of flavonoids in the concentrated extract was between 1.9 and 2.3% (w/w). The crude extract was then dissolved in deionized water and centrifuged where necessary to prepare clarified feedstock for further purification. For the method using liquid–liquid extraction with ethyl acetate, the purity, concentration ratio and yield of flavonoids were 25.4–31.0%, 16–18 and >98%, respectively. For the method using packed bed adsorption, Amberlite XAD7HP was selected as the adsorbent and clarified extract was used as the feedstock. The dynamic adsorption breakthrough curves and elution profiles were measured. For a feedstock containing flavonoids at a concentration of 0.25 mg/mL, the appropriate loading volume to reach a 5% breakthrough point during the adsorption stage was estimated to be 550–600 mL for a packed bed of volume 53 mL and a flow rate of 183 cm/h. The results from the elution stage indicated that the majority of impurities were eluted by ethanol concentrations of 40% (v/v) or below and efficient separation of flavonoids from the impurities could be achieved by elution of the flavonoids with 50–80% ethanol reaching an average purity of ∼25%. The recovery yield of flavonoids using the packed bed purification method was about 60% of the flavonoids present in the clarified feedstock (corresponding to around 30% for the total flavonoids in the unclarified crude extract). For the method using expanded bed adsorption also conducted with Amberlite XAD7HP as the adsorbent, the optimal operation conditions scouted during the packed bed experiments were used but unclarified crude extract could be loaded directly into the column. For an expanded bed with a settled bed height of 30 cm, the loss of flavonoids in the column flow-through was about 30%. The two-step elution protocol again proved to be effective in separating the adsorbed impurities and flavonoids. More than 96% of the bound impurities were completely removed by 40% ethanol in the first elution stage and less than 4% remained in the final product eluted by 90% ethanol in the second elution stage. Also, ∼74% of the adsorbed flavonoids on column (corresponding to 51% of the total flavonoids in the unclarified feedstock) were recovered in the product. In addition to higher recovery yield, the average process time to obtain the same amount of product was decreased in the expanded bed adsorption (EBA) process. The results suggest that the adoption of EBA procedures can greatly simplify the process flow sheet and in addition reduce the cost and time to purify flavonoids from Ginkgo biloba. These results clearly demonstrate the potential for the use of EBA to purify pharmaceuticals from plant sources.  相似文献   

13.
Expanded bed adsorption (EBA) is a primary recovery operation allowing the adsorption of proteins directly from unclarified feedstock, e.g. culture suspensions, homogenates or crude extracts. Thus solid-liquid separation is combined with adsorptive purification in a single step. The concept of integration requires that the solid components of the feed solution are regarded as a part of the process, which influences stability, reproducibility, and overall performance. This aspect is investigated here at the example of the influence of presence and concentration of intact yeast cells (S. cerevisiae) on the adsorption of model proteins (hen egg white lysozyme and bovine serum albumin) to various stationary phases (cation and anion-exchange, hydrophobic interaction, immobilised metal affinity). The interaction of the cells with the adsorbents is determined qualitatively and quantitatively by a pulse response method as well as by a finite bath technique under different operating conditions. The consequence of these interactions for the stability of expanded beds in suspensions of varying cell concentration is measured by residence time distributions (RTDs) after tracer pulse injection (NaBr, LiCl). Analysis of the measured RTD by the PDE model allows the calculation of the fraction of perfectly fluidised bed (phi), a parameter which may be regarded as a critical quantity for the estimation of the quality of fluidisation of adsorbents in cell containing suspensions. The correlation between bed stability and performance is made by analysing the breakthrough of model proteins during adsorption from unclarified yeast culture broth. A clear relationship is found between the degree of cell/adsorbent interaction, bed stability in terms of the phi parameter, and the sorption efficiency. Only beds characterised by a phi value larger than 0.8 in the presence of cells will show a conserved performance compared to adsorption from cell free solutions. A drop in phi, which is due to interactions of the fluidised adsorbent particles with cells from the feed, will directly result in a reduced breakthrough efficiency. The data presented highlight the importance of including the potential interaction of solid feedstock components and the expanded adsorbents into the design of EBA processes, as the interrelation found here is a key factor for the overall performance of EBA as a truly integrated operation.  相似文献   

14.
Rigid spherical macroporous adsorbent beads with surface hydroxyl groups were prepared by cross-linking of cellulose. These beads had diameter in the range 100-200 microm and a mean pore size of about 3 microm with about 60% pore volume. The matrix (bulk density approximately 1600 kg m(-3)) could be expanded into a stable bed and used for protein chromatography. Chromatographic runs were performed on a 10 mm diameter column under non-retaining and retaining conditions on the prepared matrix (called Celbeads) and performance of the runs was measured in terms of the height equivalent to a theoretical plate (HETP). The HETP curves in both packed and expanded bed modes followed profiles typical of macroporous adsorbents, i.e. increasing and levelling with velocity. Unimpaired performance of the matrix at increasing flow-rates permitted expanded bed elution of adsorbed solutes without loss of efficiency in terms of purification factor and product concentration. As a model system, Celbeads was used to purify lactate dehydrogenase from porcine muscle homogenate by dye-affinity chromatography. The prepared matrix provided about 100 theoretical plates per meter for the enzyme system at a linear flow velocity of 1.27 cm x min(-1) in an expanded bed elution mode, and gave enzyme yields of 100% with a purification factor of 31 using an optimized procedure. The adsorbent could be cleaned in place with 5 M urea and used repeatedly without loss of performance.  相似文献   

15.
This study deals with the fabrication and characterization of a pellicular adsorbent appropriate for the expanded bed adsorption (EBA) process. The synthesized adsorbent has an yttria-stabilized zirconia nucleus coated with agarose. Morphological analysis of the coated particles was performed by light-scattering microscopy and showed an average diameter of 197.54 and 202.25 µm, for the nucleus and coated particle, respectively. A screening for the reactive dyes reactive blue 19 (RB19), reactive blue 21 (RB21) and reactive orange 107 (RO107) was performed after immobilization onto the pellicular adsorbent by changing the pH, aiming at finding the binding capacity of these to adsorb bovine serum albumin (BSA). The reactive orange 107 was selected and it was more stable at pH 4.5. Study of the kinetics between BSA and the dye-immobilized particle showed that equilibrium is reached before 1 h. The adsorption isotherm of BSA onto RO107-immobilized adsorbent fitted the Langmuir model showing a qm = 102.328 mg BSA/mL of adsorbent. The pellicular adsorbent also showed good expansion even at a high operating flow rate. Therefore, at a linear velocity as high as 2725 cm/h, a dynamic capacity of 15.7 mg of BSA/mL of adsorbent was obtained.  相似文献   

16.
New adsorbents Q HyperZ and CM HyperZ composed of hydrogel-filled porous zirconium oxide particles were evaluated for expanded bed adsorption applications in the present work. The HyperZ adsorbents have wet density of 3.16 g ml(-1), particle size of 44.5-100.8 microm and average sphere diameter of 67 microm. The bed expansion as the function of flow velocity and fluid viscosity was measured and correlated with Richardson-Zaki equation. The suitable expansion factor was considered less than 2.5, while the corresponding flow velocity was about 450 cmh(-1). Liquid mixing in the bed was determined to evaluate the stability of expanded bed. The Bodenstein numbers tested were higher than 40 and the axial mixing coefficients (D(ax)) were between 0.5 and 9.7x10(-6)m(2)s(-1), which demonstrated that a stable expanded bed could be formed under suitable operation conditions. Bovine serum albumin (BSA) and lysozyme were used as model proteins to estimate the adsorption capacities of Q and CM HyperZ, respectively. The maximum equilibrium adsorption of Q and CM HyperZ could reach 45.7 and 27.2 mg g(-1) drained adsorbents, respectively. It was found that yeast cells had little influence on the adsorption capacities of the two adsorbents tested. The dynamic adsorption capacity of BSA at 10% breakthrough with Q HyperZ was 35.9 mg g(-1) drained adsorbent at flow velocity of 100 cm h(-1) for packed bed adsorption. The values for expanded bed adsorption were 34.4 mg g(-1) drained adsorbent at flow velocity of 200 cm h(-1), 33.6 mg g(-1) drained adsorbent at 300 cm h(-1) and 31.7 mg g(-1) drained adsorbent 400 cm h(-1). The results demonstrated that Q HyperZ and CM HyperZ are suitable for expanded bed adsorption of biomolecules.  相似文献   

17.
Affinity purification of proteins using expanded beds.   总被引:5,自引:0,他引:5  
The use of expanded beds of affinity adsorbents for the purification of proteins from feedstocks containing whole or broken cells is described. It is demonstrated that such feedstocks can be applied to the bed without prior removal of particulate material by centrifugation or filtration thus showing considerable potential for this approach in simplifying downstream processing flow-sheets. A stable, expanded bed can be obtained using simple equipment adapted from that used for conventional packed bed adsorption and chromatography processes. Circulation and mixing of the adsorbent particles is minimal and liquid flow through the expanded bed shows characteristics similar to those of plug flow. Frontal analysis performed with the highly selective affinity system involving the adsorption of human polyclonal immunoglobulin G onto Protein A Sepharose Fast Flow indicate that the adsorption performance of the expanded bed is similar to that achieved when the same amount of adsorbent is used in a packed configuration at the same volumetric flow-rate. The adsorption performance of the expanded bed was not diminished when adsorption was carried out in the presence of intact yeast cells. Batch adsorption experiments also indicated that the adsorption characteristics of the affinity system were not greatly altered in the presence of cells in contrast to results from a less selective ion-exchange system. An expanded bed of Cibacron Blue Sepharose Fast Flow was used to purify phosphofructokinase from feedstock of disrupted yeast prepared by high pressure homogenisation without the need for prior removal of particulate material. The potential for the use of expanded beds in large scale purification systems is discussed.  相似文献   

18.
Macroporous copolymer matrix. IV. Expanded bed adsorption application   总被引:2,自引:0,他引:2  
Macroporous crosslinked hydroxyethyl methacrylate-ethylene dimethacrylate copolymeric beads (HEG beads) were synthesized by suspension polymerization in the presence of a pore generating agent. These beads were coupled to alpha-cyclodextrin through a urethane spacer. These modified copolymer beads (affinity-HEG beads) so prepared were evaluated for their suitability in expanded bed chromatography. The optimum thickness of the distributor plate for stable expanded bed for use in expanded bed adsorption (EBA) was established. The affinity-HEG beads are comparable in density to Streamline diethyl amino ethane (DEAE) and exhibit better mechanical stability at higher superficial velocity under fluidization. The affinity-BEG beads were used as affinity chromatography matrices for the purification of cyclodextrin glycosyltransferase. Feeding of 5-fold diluted fermented broth to the column containing affinity-HEG beads of settled bed height 7.5 cm (I.D. 26 mm and length 42 cm) at double bed expansion resulted in a sharp breakthrough curve of alpha-cyclodextrin glycosyltransferase (CGTase). The adsorbed enzyme was eluted from the bed in 50 mM Tris-HCl buffer containing 10 mM CaCl2 at 25 degrees C in packed bed configuration.  相似文献   

19.
The expansion and hydrodynamic properties of matrix are significant for expanded bed adsorption (EBA) processes. A series of new composite matrices CroCD-TuC are studied and estimated in an expanded bed. It is found that the heavier matrix is better suited for high operation fluid velocity than the lighters. Although the Richardson–Zaki equation can well correlate the bed voidage with fluid velocity for all CroCD-TuC matrices tested, the modifications are proposed to improve the accuracy of theoretical predictions of correlation parameters, including terminal settling velocity (Ut) and expansion index (n). Residence time distributions (RTDs) are determined, and the Bodenstein number (Bo) and axial dispersion coefficient (Dax) are employed to analyze the liquid mixing in the expanded bed. It is found for CroCD-TuC matrices, both parameters notably changed with the variation of fluid velocity and viscosity. Furthermore, Dax is an intuitive parameter estimating the bed stability on various operating conditions, and also a restriction on developing the matrix for high operation fluid velocity. The comparison of the hydrodynamic properties on different matrices reveals that CroCD-TuC 3 and CroCD-TuC 4 seem superior to other matrices in hydrodynamic properties, making them promising matrices for further use. The correlations as the functions of fluid velocity and viscosity have been established which may provide beneficial information for practical applications of CroCD-TuC matrices in EBA processes.  相似文献   

20.
The suitability of the use of macroporous adsorbent Amberlite XAD7HP in expanded bed adsorption processes for the isolation of flavonoids from crude extracts of Ginkgo biloba L. has been assessed. The expansion and hydrodynamic properties of expanded beds were investigated and analyzed. The bed expansion as a function of operational fluid velocity was measured and correlated with the Richardson–Zaki equation. Theoretical predictions of the correlation parameters (the terminal settling velocity ut and exponent n) were improved by modifying equations in the literature. Residence time distributions (RTDs) were studied using acetone as a tracer. Three measures of liquid phase dispersion (the height equivalent of theoretical plate, Bodenstein number and axial distribution coefficient) were investigated and compared to values previously obtained with commercial EBA adsorbents developed for protein purification. A suitable bed expansion ratio was found to be 1.25 times the settled bed height, which occurred at a corresponding flow velocity of 183 cm/h. For an initial settled bed height of 42 cm, the mean residence time of liquid in the expanded bed was around 28 min. Under these flow conditions, the axial mixing coefficient Dax was 7.54 × 10−6 m2/s and the Bodenstein number was 28; the number of theoretical plates (N) was 19 and the height equivalent of a theoretical plate (HETP) was 2.77 cm. Rutin trihydrate was used as a model flavonoid for the characterization of the adsorption properties of Amberlite XAD7HP. Adsorption was observed to reach equilibrium within 3 h with 70% of the adsorption capacity being achieved within 30 min. The estimated maximum equilibrium adsorption capacity for rutin was estimated to be 43.0 mg/(g resin) when the results were fitted to Langmuir isotherms. The adsorption performance was not seriously impaired by the physical presence of G. biloba leaf powders. Assessment of the kinetics of the adsorption of rutin revealed that the rate constant for adsorption was only reduced by 15% in the presence of leaf powders at a concentration of 50 mg/mL. The results demonstrated that Amberlite XAD7HP should be suitable for expanded bed adsorption of flavonoids from crude extracts of G. biloba L.  相似文献   

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