纤维素亲和膜对木瓜蛋白酶的吸附特性

以纤维素滤纸膜为载体,染料汽巴蓝F3GA为配基,制备出一种新型亲和膜色谱介质。分别在277,298,310K的均衡实验条件下,批量法对木瓜蛋白酶进行等温吸附测定。所得的数据用准一级动力学模型和准二级动力学模型进行分析。结果表明:准二级动力学模型具有更好的相关性,纤维素染料亲和膜对木瓜蛋白酶的吸附符合Lang-muir吸附模型,在298K条件下吸附现象的热力学参数:ΔGΘ,ΔHΘ,ΔSΘ分别为-7.71kJ/mol,34.91kJ/mol和0.143kJ/(mol.K),染料纤维素亲和膜对木瓜蛋白酶的吸附是自发的,并且是吸热过程。     

纤维素纳米纤维膜的改性及其染料吸附性能

采用静电纺丝技术制备醋酸纤维素纳米纤维膜,用氢氧化锂水解后得到纤维素纳米纤维膜。通过3-氯-2-羟丙基三甲基氯化铵(CHPTAC)和一氯乙酸共同改性,制备了双性纤维素纳米纤维膜。利用紫外-可见分光光度计测试双性纤维素纳米纤维膜对茜素绿(AG25)和亚甲基蓝(MB)的吸附性能,并考察了溶液初始pH、温度、染料初始质量浓度对吸附量的影响。结果表明,双性纤维素纳米纤维膜对AG25和MB染料的最大吸附量分别达到240和128 mg/g,并且对两种染料在第4次循环使用时仍保持84.44%以上的吸附效率。同时,发现pH是影响双性纤维素纳米纤维膜对染料吸附性能的关键因素,在吸附没有达到饱和之前,染料吸附量随着染料质量浓度的增加而增加,而吸附效果对温度没有依赖性。     

纳米纤维素膜制备及其用于染料废水分离的研究

采用涂敷法制备了以纳米纤维素为分离层的复合纳滤膜,通过调节纳米纤维素铸膜液的pH,解决了铸膜液在聚砜底膜上粘合力不强、难以成膜的问题,研究了交联剂对膜性能的影响。结果表明：经戊二醛交联的纳米纤维素膜稳定性更好、截留率更高;交联膜对刚果红、橙黄G两种染料的截留率可至95%以上。     

固定化铜离子亲和膜静态吸附血红蛋白的性能研究

用固定化铜离子亲和膜静态吸附血红蛋白(Hb),考察了血红蛋白浓度、pH值、离子强度、温度和时间对吸附的影响.结果表明,固定化铜离子亲和膜静态吸附血红蛋白的最大吸附量为14.8719 mg·g-1,当控制温度16～25℃、pH值7.0 ～ 7.4、Hb浓度0.8484 ～ 1.2726 mg·mL-1时,吸附效果较好;离子强度越低,吸附效果越好;吸附时间至少为30 min.固定化铜离子亲和膜静态吸附血红蛋白的研究为实际体系的分离研究奠定了基础.     

交联羧甲基纤维素的制备及对染料吸附性能的研究

酸催化下,取代度0.82的羧甲基纤维素钠(CMC)经固相加热反应,制备吸附材料交联羧甲基纤维素(CCMC)。研究反应条件对CCMC交联度、交联度对CCMC吸附碱性品红(BF)和亚甲基蓝(MB)性能的影响。结果表明,酸浓度对CCMC交联度影响最大,交联度0.39的CCMC的吸附性能最佳。以交联度0.39的CCMC为吸附剂,研究吸附条件包括固液比、染料初始浓度、pH、吸附时间对CCMC吸附性能的影响。20℃,固液比0.25 g/L条件下,CCMC对BF和MB的饱和吸附量分别为570 mg/g和540 mg/g。     

交联羧甲基纤维素的制备及对染料吸附性能的研究

酸催化下,取代度0.82的羧甲基纤维素钠(CMC)经固相加热反应,制备吸附材料交联羧甲基纤维素(CCMC)。研究反应条件对CCMC交联度、交联度对CCMC吸附碱性品红(BF)和亚甲基蓝(MB)性能的影响。结果表明,酸浓度对CCMC交联度影响最大,交联度0.39的CCMC的吸附性能最佳。以交联度0.39的CCMC为吸附剂,研究吸附条件包括固液比、染料初始浓度、pH、吸附时间对CCMC吸附性能的影响。20℃,固液比0.25 g/L条件下,CCMC对BF和MB的饱和吸附量分别为570 mg/g和540 mg/g。     

巯基-烯修饰纤维素气凝胶的制备及其染料吸附的研究

采用一步法制备出乙烯基三甲氧基硅烷改性的气凝胶(SA),并用巯基-烯点击反应将巯基丙酸(MPA)和半胱胺盐酸盐(Cys)接枝到SA气凝胶上得到功能化气凝胶。通过扫描电子显微镜(SEM)、傅里叶变换红外光谱(FT-IR)、机械性能测试等对气凝胶进行表征。实验结果表明,氨基化气凝胶(SA-Cys)和羧基化气凝胶(SA-MPA)都具有良好的机械性能,其中SA-MPA压缩强度可达到86 KPa,压缩模量也可达到90 KPa。选用阴离子型染料活性蓝KN-R和阳离子型染料罗丹明B(Rh-B)来研究SA-Cys和SA-MPA的吸附性能。研究结果表明,SA-MPA与SA-Cys有良好的吸附性能,而且都可以重复吸附染料。     

固定化Cu~(2+)螯合亲和膜的制备及其吸附研究

以尼龙66为基膜,环氧氯丙烷为活化剂,壳聚糖为交联剂,亚胺基二乙酸为螯合剂,Cu~(2+)为配位基,制备了固定化Cu~(2+)螯合亲和膜。讨论了该膜对牛血清蛋白(BSA)的吸附机理;研究了BSA溶液初始浓度、pH值和吸附时间对亲和膜吸附量的影响,采用SEM对其表面形貌进行表征。结果表明:较高的BSA初始浓度和pH值,较长的吸附时间均有利于膜对BSA的吸附;Langmuir吸附等温模型和准二级动力学模型可用于该膜对BSA的吸附相关性。     

胺基化多孔再生纤维素膜的制备及其吸附性能的研究

在制备多孔再生纤维素膜的基础上,采用固-固相界面反应的TEMPO氧化法制备了氧化纤维素膜,通过乙二胺接枝改性成功制备了一种胺基化多孔再生纤维素膜。采用红外光谱、X-射线衍射、扫描电镜等对其结构进行表征,并研究了其对阴离子染料二甲酚橙的吸附性能。实验结果表明:改性纤维素膜上成功引入了胺基,且保留了多孔的纤维素膜结构;该改性膜对二甲酚橙具有良好的吸附效果,能够较快达到吸附平衡,其染料去除率高达92%。该吸附过程符合准二级动力学方程和Freundlich等温方程。     

离子液体法纤维素氨基甲酸酯再生膜的制备及性能研究

以氯化1-烯丙基-3甲基咪唑(AMIMC1)为溶剂,纤维素氨基甲酸酯(CC)溶液为铸膜液,制备了再生纤维素膜,采用红外光谱(FTIR)、X射线衍射(XRD)、热重(TG)、扫描电子显微镜(SEM)、拉伸、染料截留等方法对膜的结构和性能进行测试分析.结果表明,再生纤维素膜有致密的表面和断面,湿膜、干膜的断裂强度分别为7....     

聚丙烯膜接枝改性亲和膜的制备与表征

采用预辐射接枝法在聚丙烯基膜(PP)上接枝甲基丙烯酸缩水甘油酯(GMA),再将配基辛巴蓝(CBD)固载于GMA聚合链上制备了一种亲和膜.考察了预辐射剂量、接枝单体浓度、反应时间和温度、Mohr's盐浓度对GMA聚合接枝的影响,获得了较佳的条件:GMA浓度20%(v/v),反应温度70℃,反应时间3h,Mohr's盐浓度0.01%(wt),CBD溶液浓度25mg·mL-1.用红外光谱 (FTIR)和扫描电镜 (SEM)分析和观察了该亲和膜的表面形貌特征;在37℃和60mg·L-1的胆红素溶液中对该亲和膜进行静态吸附平衡实验,结果表明,经2.5 h吸附达到平衡,其吸附容量可达50mg·g-1.     

In vitro cadmium removal from human serum by Cibacron Blue F3GA–thionein‐complex conjugated affinity membranes

A new membrane affinity biosorbent carrying thionein has been developed for selective removal of cadmium ions from human serum. Microporous poly(2‐hydroxyethyl methacrylate) (pHEMA) membranes were prepared by photopolymerization of HEMA. The pseudo dye ligand Cibacron Blue F3GA (CB) was covalently immobilized on the pHEMA membranes. Then, the cysteine‐rich metallopeptide thionein was conjugated onto the CB‐immobilized membrane. The maximum amounts of CB immobilized and thionein conjugated on the membranes were 1.07 µmol cm⁻² and 0.92 µmol cm⁻², respectively. The hydrophilic pHEMA membrane had a swelling ratio of 58% (w/w) with a contact angle of 45.8 °. CB‐immobilized and CB‐immobilized–thionein‐conjugated membranes were used in the Cd(II) removal studies. Cd(II) ion adsorption appeared to reach equilibrium within 30 min and to follow a typical Langmuir adsorption isotherm. The maximum capacity (q _m) of the CB‐immobilized membranes was 0.203 (µmol Cd(II)) cm⁻² membrane and increased to 1.48 (µmol Cd(II)) cm⁻² upon CB–thionein‐complex conjugation. The pHEMA membranes retained their cadmium adsorption capacity even after 10 cycles of repeated use. © 2000 Society of Chemical Industry     

Synthesis of Cibacron Blue F3GA‐coupled magnetic PMMA nanospheres and their use for protein affinity separation

BACKGROUND: New magnetic carrier separation technologies, capable of treating dilute solutions in large‐scale processes, even in the presence of biological debris, are necessary for the future development of biotechnology. Non‐porous magnetic carriers are more resistant to fouling, show better mass transfer and have lower non‐specific adsorption than porous carriers. Nanosized magnetic carriers have a surface area comparable to that of typical macroporous resins, and therefore their application has advantages. RESULTS: Magnetic poly(methyl methacrylate) (PMMA) nanospheres with an average diameter of 76 nm and narrow size distribution were prepared by a facile mini‐emulsion polymerization. After surface modification with poly(ethylene glycol), Cibacron Blue F3GA (CB) was coupled to the magnetic PMMA nanospheres to form dye ligand‐attached magnetic adsorbents for bovine serum albumin (BSA) adsorption. The CB‐coupled magnetic PMMA nanospheres showed very high adsorption capacity (121.98 mg g^?1) and little non‐specific adsorption for BSA. The adsorbed protein could be easily desorbed using high ionic strength solution. CONCLUSION: The CB‐coupled magnetic PMMA nanospheres showed a high BSA adsorption capacity, low non‐specific adsorption and fast adsorption kinetics in comparison with other dye‐affinity adsorbents. These characteristics indicate that these magnetic PMMA nanospheres have great potential for protein affinity separation and purification. Copyright © 2009 Society of Chemical Industry     

Affinity microspheres and their application to lysozyme adsorption: Cibacron Blue F3GA and Cu(II) with poly(HEMA-EGDMA)

Lysozyme adsorption onto Cibacron Blue F3GA attached and Cu(II) incorporated poly(2-hydroxyethyl methacrylate–ethylene glycol dimethacrylate) [poly(HEMA-EGDMA)] microspheres was investigated. The microspheres were prepared by suspension polymerization. Various amounts of Cibacron Blue F3GA were attached covalently onto the microspheres by changing the initial concentration of dye in the reaction medium. The microspheres with a swelling ratio of 65%, and carrying different amounts of dye (between 1.4 and 22.5 µmol/g⁻¹) were used in the lysozyme adsorption studies. Lysozyme adsorption on these microspheres from aqueous solutions containing different amounts of lysozyme at different pH values was investigated in batch reactors. The lysozyme adsorption capacity of the dye–metal chelated microspheres (238.2 mg g⁻¹) was greater than that of the dye-attached microspheres (175.1 mg g⁻¹). The maximum lyzozyme adsorption capacities (q_m) and the dissociation constant (k_d) values were found to be 204.9 mg g⁻¹ and 0.0715 mg ml⁻¹ with dye-attached and 270.7 mg g⁻¹ and 0.0583 mg ml⁻¹ with dye–metal chelated microspheres, respectively. More than 90% of the adsorbed lysozyme were desorbed in 60 min in the desorption medium containing 0.5 M KSCN at pH 8.0 or 25 mM EDTA at pH 4.9. © 1999 Society of Chemical Industry     

New metal chelate sorbent for albumin adsorption: Cibacron Blue F3GA-Zn(II) attached microporous poly(HEMA) membranes

Poly(2-hydroxyethyl methacrylate) [poly(HEMA)] membranes were prepared by UV-initiated photopolymerization of HEMA in the presence of an initiator (α-α′-azobis-isobutyronitrile, AIBN). The triazine dye Cibacron Blue F3GA was attached as an affinity ligand to poly(HEMA) membranes, covalently. These affinity membranes with a swelling ratio of 58% and containing 10.7 mmol Cibacron Blue F3GA/m² were used in the albumin adsorption studies. After dye-attachment, Zn(II) ions were chelated within the membranes via attached-dye molecules. Different amounts of Zn(II) ions [650–1440 mg Zn(II)/m²] were loaded on the membranes by changing the initial concentration of Zn(II) ions and pH. Bovine serum albumin (BSA) adsorption on these membranes from aqueous solutions containing different amounts of BSA at different pH was investigated in batch reactors. The nonspecific adsorption of BSA on the poly(HEMA) membranes was negligible. Cibacron Blue F3GA attachment significantly increased the BSA adsorption up to 92.1 mg BSA/m². Adsorption capacity was further increased when Zn(II) ions were attached (up to 144.8 mg BSA m²). More than 90% of the adsorbed BSA was desorbed in 1 h in the desorption medium containing 0.5M NaSCN at pH 8.0 and 0.025M EDTA at pH 4.9. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 657–664, 1998     

Cibacron Blue F3GA‐attached magnetic poly(2‐hydroxyethyl methacrylate) beads for human serum albumin adsorption

An affinity dye ligand, Cibacron Blue F3GA, was covalently attached onto magnetic poly(2‐hydroxyethyl methacrylate) (mPHEMA) beads for human serum albumin (HSA) adsorption from both aqueous solutions and human plasma. The mPHEMA beads, in the size range of 80 to 120 µm, were prepared by a modified suspension technique. Cibacron Blue F3GA molecules were incorporated on to the mPHEMA beads. The maximum amount of Cibacron Blue F3GA attachment was obtained as 68.3 µmol g^?1. HSA adsorption onto unmodified and Cibacron Blue F3GA‐attached mPHEMA beads was investigated batchwise. The non‐specific adsorption of HSA was very low (1.8 mg g^?1). Cibacron Blue F3GA attachment onto the beads significantly increased the HSA adsorption (94.5 mg g^?1). The maximum HSA adsorption was observed at pH 5.0. Higher HSA adsorption was observed from human plasma (138.3 mg HSA g^?1). Desorption of HSA from Cibacron Blue F3GA‐attached mPHEMA beads was obtained by using 0.1 M Tris/HCl buffer containing 0.5 M NaSCN. High desorption ratios (up to 98% of the adsorbed HSA) were observed. It was possible to re‐use Cibacron Blue F3GA‐attached mPHEMA beads without any significant decreases in their adsorption capacities. Copyright © 2004 Society of Chemical Industry     

Metal chelating properties of Cibacron Blue F3GA‐derived poly(EGDMA‐HEMA) microbeads

Metal chelating properties of Cibacron Blue F3GA‐derived poly(EGDMA‐HEMA) microbeads have been studied. Poly(EGDMA‐HEMA) microbeads were prepared by suspension copolymerization of ethylene glycol dimethacrylate (EGDMA) and hydroxy‐ethyl methacrylate (HEMA) by using poly(vinyl alcohol), benzoyl peroxide, and toluene as the stabilizer, the initiator, and the pore‐former, respectively. Cibacron Blue F3GA was covalently attached to the microbeads via the nucleophilic substitution reaction between the chloride of its triazine ring and the hydroxyl groups of the HEMA, under alkaline conditions. Microbeads (150–200 μm in diameter) with a swelling ratio of 55%, and carrying 16.5 μmol Cibacron Blue F3GA/g polymer were used in the adsorption/desorption studies. Adsorption capacity of the microbeads for the selected metal ions, i.e., Cu(II), Zn(II), Cd(II), Fe(III), and Pb(II) were investigated in aqueous media containing different amounts of these ions (5–200 ppm) and at different pH values (2.0–7.0). The maximum adsorptions of metal ions onto the Cibacron Blue F3GA‐derived microbeads were 0.19 mmol/g for Cu(II), 0.34 mmol/g for Zn(II), 0.40 mmol/g for Cd(II), 0.91 mmol/g for Fe(III), and 1.05 mmol/g for Pb(II). Desorption of metal ions were studied by using 0.1 M HNO₃. High desorption ratios (up to 97%) were observed in all cases. Repeated adsorption/desorption operations showed the feasibility of repeated use of this novel sorbent system. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1397–1403, 1999     

Dye derived and metal incorporated affinity poly(2-hydroxyethyl methacrylate) membranes for use in enzyme immobilization

Microporous poly(2-hydroxyethyl methacrylate) (PHEMA) membranes were prepared by UV-initiated photopolymerization of HEMA in the presence of an initiator (α,α′-azobisisobutyronitrile, AIBN). An affinity dye Cibacron Blue F3GA (CB) was attached covalently and then Fe³⁺ ions incorporated. The PHEMA-CB and PHEMA-CB-Fe³⁺ membranes derived were used for adsorption of glucose oxidase (GOD). The adsorption capacities of these membranes were determined under conditions of different pH and with different concentrations of the adsorbate in the medium. The adsorption phenomena appeared to follow a typical Langmuir isotherm. The glucose oxidase adsorption capacity of the Fe³⁺ incorporated membrane (87μgcm^-2) was greater than that of the dye-derived membrane (66μgcm^-2). Non-specific adsorption of the glucose oxidase on the PHEMA membranes was negligible. The K_m values for both immobilized glucose oxidase PHEMA-CB-GOD (8·3) and PHEMA-CB-Fe³⁺-GOD (7·6) were higher than that of the free enzyme (6·2mM). Optimum reaction pH was 5·5 for the free and 6·0 for both immobilized preparations. The optimum reaction temperature of the adsorbed enzymes was 5°C higher than that of the free enzyme and was significantly broader. After 15 successive uses the retained activity of the adsorbed enzyme was 87%. It was observed that enzymes could be repeatedly adsorbed and desorbed on the derived PHEMA membranes without significant loss in adsorption capacity or enzymic activity. © 1998 SCI.     

Albumin adsorption from aqueous solutions and human plasma in a packed-bed column with Cibacron Blue F3GA-Zn(II) attached poly(EGDMA-HEMA) microbeads

Affinity dye-ligand Cibacron Blue F3GA, was covalently coupled with poly(EGDMA-HEMA) microbeads via nucleophilic reaction between the chloride of its triazine ring and the hydroxyl groups of the HEMA under alkaline conditions. The microbeads carrying 16.5 μmol Cibacron Blue F3GA per gram polymer was incorporated with Zn(II) ions. Zn(II) loading was 189.6 μmol/g. Cibacron Blue F3GA-Zn(II) attached affinity sorbent was used for albumin adsorption from aqueous solutions and human plasma in a packed-bed column. BSA adsorption capacity of the microbeads decreased with an increase in the recirculation rate. High adsorption rates were observed at the beginning, then equilibrium was gradually achieved in about 60 min. The BSA concentration in the mobile phase also effected adsorption. BSA adsorption was first increased with BSA concentration, then reached a plateau which was about 128 mg BSA/g. The maximum adsorption was observed at pH 5.0 which is the isoelectric pH of BSA. Higher human serum albumin adsorption was observed from human plasma (215 mg HSA/g). High desorption ratios (over 90% of the adsorbed albumin) were achieved by using 1.0 M NaSCN (pH 8.0) in 30 min.