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1.
Highly efficient removal of endocrine‐disrupting compounds (EDCs) such as 17β‐estradiol (E2), 4‐nonylphenol (NP) and atrazine from water was achieved using a novel macroporous adsorption medium. The medium consisted of a macroporous poly(vinyl alcohol) (PVA) cryogel with molecularly imprinted polymer (MIP) particles embedded in it. The MIP was prepared using E2, NP and atrazine as templates. The macroporous composite molecularly imprinted cryogels were formed inside the open‐ended protective shells, known as Kaldnes carriers. These adsorbents (defined as Macroporous Gel Particles, MGPs) were evaluated on the removal of E2, NP and atrazine from water using different column configurations, namely column filled with the MGPs (packed‐bed column) and in moving‐bed reactors (defined here as moving‐bed MGPs reactor). Complete binding (> 99%) of E2 from a spiked aqueous solution (1 mg/L) was achieved using E2‐MIP/MGPs in a moving‐bed MGPs reactor at the retention time in the reactor of 4 min, while only 77% was bound to the nonimprinted medium (NIP/MGPs). Similar results were also obtained for the adsorption medium imprinted with atrazine. All contaminants studied (E2, atrazine and NP) were effectively removed from water at low (environmentally relevant) concentrations by the respective adsorption medium.  相似文献   

2.
The protein C imprinted monolithic cryogel was synthesized using 2‐hydroxyethyl methacrylate by redox cryo‐polymerization method. The prepared monolithic cryogel was characterized by Fourier transform infrared spectroscopy, swelling test, surface area measurements, and scanning electron microscopy. The nonimprinted cryogel was prepared as well for control. Adsorption of protein C from aqueous solutions was investigated in a continuous mode and several parameters affecting adsorption performance were optimized. The maximum protein C adsorption amount was 30.4 mg/g. The selectivity studies were performed by monolithic column studies and fast protein liquid chromatography, using hemoglobin and human serum albumin as competing proteins. The relative selectivity coefficients were 2.37 and 8.89 for hemoglobin and human serum albumin, respectively. Reusability was tested for ten consecutive adsorption–desorption cycles, and no significant change in adsorption capacity was recorded. A pseudo‐second‐order model was suitable to interpret kinetic data, and the Langmuir model suited the adsorption isotherms well.  相似文献   

3.
Creatinine imprinted cryogel (MIP) cartridge was prepared with functional monomer N-methacryloyl-(L)-histidinemethylester (MAH) under frozen conditions. Creatinine adsorption studies and selectivity of MIP cryogel were evaluated in aqueous solution and artificial urine sample. Maximum adsorbed amount of creatinine was calculated as 6.83 mg/g polymer for MIP cryogel. Langmuir and Freundlich adsorption isotherm models were used to investigate the adsorption behaviour of creatinine. In the artificial urine sample; recovery amounts of creatinine were found 34.7–46.2%. Creatinine imprinted cryogel (MIP) cartridge recognized creatinine, 4.58 and 4.37 times greater competitive molecules. MIP cryogel catridge was repeatedly used many times for adsorption desorption cycles.  相似文献   

4.
Cryogels have been demonstrated to be efficient when applied for protein isolation. Owing to their macroporous structure, cryogels can also be used for treating particle‐containing material, e.g. cell homogenates. Another challenging development in protein purification technology is the use of molecularly imprinted polymers (MIPs). These MIPs are robust and can be used repeatedly. The paper presents a new technology that combine the formation of cryogel beads concomitantly with making imprints of a protein. Protein A was chosen as the print molecule which was also be the target in the purification step. The present paper describes a new method to produce protein‐imprinted cryogel beads. The protein‐imprinted material was characterized and the separation properties were evaluated with regard to both the target protein and whole cells with target protein exposed on the cell surface. The maximum protein A adsorption was 18.1 mg/g of wet cryogel beads. The selectivity coefficient of protein A‐imprinted cryogel beads for protein A was 5.44 and 12.56 times greater than for the Fc fragment of IgG and protein G, respectively.  相似文献   

5.
Cibacron Blue F3GA was immobilized on poly(hydroxyethyl methacrylate) cryogel and it was used for selective and efficient depletion of albumin from human serum. The poly(hydroxyethyl methacrylate) was selected as the basic component because of its inertness, mechanical strength, chemical and biological stability, and biocompatibility. Cibacron Blue F3GA was covalently attached to the poly(hydroxyethyl methacrylate) cryogel to produce poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel affinity column. The poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel was characterized with respect to gelation yield, swelling degree, total volume of macropores, Fourier Transform Infrared spectroscopy, and scanning electron microscopy. It was found that the maximum amount of adsorption (343 mg/g of dry cryogel) obtained from experimental results is very close to the calculated Langmuir adsorption capacity (345 mg/g of dry cryogel). The maximum adsorption capacity for poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel column was obtained as 950 mg/g of dry cryogel for nondiluted serum. The adsorption capacity decreased with increasing dilution ratios while the depletion ratio of albumin remained as 77% in serum sample. Finally, the poly(hydroxyethyl methacrylate)-Cibacron Blue F3GA cryogel was optimized for using in the fast protein liquid chromatography system for rapid removal of the high abundant proteins from the human serum.  相似文献   

6.
通过7-乙酰氧基-4-甲基香豆素作为黄曲霉毒素的替代模板合成分子印迹聚合物,使用紫外可见分光光度计测定聚合物对黄曲霉毒素的吸附,并进行合成条件优化。使用傅里叶变换红外、电子显微镜扫描、激光粒度分析仪对聚合物进行表征。对分子印迹聚合物进行吸附性能测试,得到分子印迹聚合物的最大吸附量为5.0 mg/g。将聚合物作为柱填料制备固相萃取柱检测黄曲霉毒素,并与免疫亲和柱对比,自制柱效果较好。  相似文献   

7.
This work was aimed to synthesize and characterize poly(2‐hydroxyethyl methacrylate) [poly (HEMA)]‐based molecularly imprinted polymer nanoparticles (MIP NPs) containing timolol maleate (TM) via precipitation polymerization. The molecular structures of the MIP and non‐imprinted polymer (NIP) NPs were compared by means of Fourier transform infrared spectroscopy. The morphological observations by using scanning electron microscopy and transmission electron microscopy confirmed the formation of MIP NPs as small as 128 nm in average diameter with appropriate synthesis conditions. Thermal behaviors of the samples were also studied by the use of thermogravimetric analysis and differential scanning calorimetry. By considering a series of key factors such as monomer : template ratio, cross‐linker type, pH, and temperature, the sample with promising characteristics was found to be that of HEMA : TM ratio of 10:1, 40 mmol of ethylene glycol dimethacrylate as cross‐linker, and polymerization temperature of 60°C in acetonitrile as porogenic solvent. Furthermore, the ultraviolet‐visible (UV‐vis) spectrophotometry results proved a controlled release of TM from the MIP NP samples compared with NIP ones at extended periods. Moreover, the cytotoxicity of the MIP and NIP NPs samples was evaluated on mesenchymal stem cells, and the obtained observations showed that they had no adverse side effect on the living cells; especially the surface of the MIP NPs sample depicted highly cell's biocompatibility. Finally, the outcomes from designed different experiments conducted us that the HEMA‐based MIP NPs have great potential as an ocular nanocarrier for TM delivery. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

8.
Molecular imprinting is an attractive biomimetic approach that creates specific recognition sites for the shape and functional group arrangement to template molecules. The purpose of this study is to prepare cytochrome c-imprinted poly(hydroxyethyl methacrylate) (PHEMA)-based supermacroporous cryogel which can be used for the separation of cytochrome c from protein mixtures. N-Methacryloyl-(L)-histidinemethylester (MAH) was used as the metal-coordinating monomer. In the first step, Cu(2+) was complexed with MAH, and the cytochrome c imprinted PHEMA (MIP) cryogel was prepared by free radical cryopolymerization initiated by N,N,N',N'-tetramethylene diamine at -12°C. After polymerization is completed, the template cytochrome c molecules were removed from the MIP cryogel using 0.5 M NaCl solution. The maximum cytochrome c binding amount was 126 mg/g polymer. Selective binding studies were performed in the presence of lysozyme and bovine serum albumin. The relative selectivity coefficients of MIP cryogel for cytochrome c/lysozyme and cytochrome c/bovine serum albumin were 1.7 and 5.2 times greater than those of the non-imprinted PHEMA cryogel, respectively. The selectivity of MIP cryogel for cytochrome c was also confirmed with fast protein liquid chromatography. The MIP cryogel could be used many times with no remarkable decrease in cytochrome c binding capacity.  相似文献   

9.
Bovine milk whey contains several bioactive proteins such as α‐lactalbumin, β‐lactoglobulin, and immunoglobulin G (IgG). Chromatographic separation of these proteins has received much attention in the past few years. In this work, we provide a chromatographic method for the efficient isolation of IgG from bovine milk whey using a poly(2‐hydroxyethyl methacrylate)‐based anion‐exchange cryogel. The monolithic cryogel was prepared by grafting 2‐(dimethylamino) ethyl methacrylate onto the poly(2‐hydroxyethyl methacrylate)‐based cryogel matrix and then employed to separate IgG under various buffer pH and salt elution conditions. The results showed that the buffer pH and the salt concentration in the step elution have remarkable influences on the purity of IgG, while the IgG recovery depended mainly on the loading volume of whey for a given cryogel bed. High purity IgG (more than 95%) was obtained using the phosphate buffer with pH of 5.8 as the running buffer and the salt solution in as the elution liquid. With suitable loading volume of whey, the maximum IgG recovery of about 94% was observed. The present separation method is thus a potential choice for the isolation of high‐purity IgG from bovine milk whey.  相似文献   

10.
《先进技术聚合物》2018,29(8):2401-2409
The objective of this work was to synthesize molecularly imprinted polymer (MIP) nanoparticles based on methacrylic acid (MAA) monomer with a high selectivity against an anti‐cancer drug, 5‐fluorouracil (5‐FU), as a template. In this case, the nanoparticles were prepared via precipitation polymerization in the presence of ethylene glycol dimethacrylate as cross‐linker and azobisisobutyronitrile as initiator. Besides, 3 independent variables including MAA: 5‐FU molar ratio (X1), temperature (X2), and time (X3) were investigated utilizing response surface methodology. The scanning electron microscopy and dynamic light scattering resulted the average diameter of approximately 65 nm, and the MIP nanoparticle sample with the imprinting factor of 1.57 was polymerized in optimized conditions as follows: X1 = 6: 1, X2 = 60°C, and X3 = 3 days in acetonitrile as porogenic solvent. Also, Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis confirmed the formation of MAA/5‐FU complex and lower thermal stability of the washed MIP sample than the unwashed MIP and non‐imprinted polymer (NIP) samples, respectively. Moreover, the optimized MIP nanoparticles have more controlled release of 5‐FU rather than the NIP sample. Finally, the flow cytometry showed that 5‐FU‐loaded MIP sample has the highest apoptosis of human colon cancer cell line, HCT‐116, after 3 days compared with NIP sample and also the exclusive use of drug.  相似文献   

11.
A DNA probe that was based on methylene blue (MB) imprinted polyvinyl pyridine polymer (MIP) modified carbon paste electrodes were developed for the first time for electrochemical monitoring of DNA. Probes were built up by adsorbing MB onto modified electrodes prior to DNA immobilization. It was shown that DNA strongly immobilizes on MIP modified electrodes when MB was adsorbed in advance of DNA immobilization. The performance of the MB imprinted polymer modified carbon paste electrodes (MIP‐CPE) to rebind the template molecule (MB) were compared to those of control polymer modified (non‐imprinted polymer NIP‐CPE) and bare (CPE) electrodes. Electrochemical signal resulting from the oxidation of guanine moiety of the immobilized probe DNA was high enough on the constructed platform, implicating that probes of this kind could be favorably used for DNA analysis. These probes exhibited high selectivity for its complementary DNA sequences (target). HBV‐DNA hybridization was studied to evaluate the selectivity of the probes for complementary, non‐complementary and mismatch sequences. The detection limit of the probe for the target DNA was 8.72 µg/mL (1.38 µM), which was better than those attained by some earlier DNA sensor studies.  相似文献   

12.
As alternative hydrophobic adsorbent for DNA adsorption, supermacroporous cryogel disks were synthesized via free radical polymerization. In this study, we have prepared two kinds of cryogel disks: (i) poly(2‐hydroxyethyl methacrylate‐N‐methacryloyl‐l ‐tryptophan) [p(HEMA‐MATrp)] cryogel containing specific hydrophobic ligand MATrp; and (ii) monosize p(HEMA‐MATrp) particles synthesized via suspension polymerization embedded into p(HEMA) cryogel structure to obtain p(HEMA‐MATrp)/p(HEMA) composite cryogel disks. These cryogel disks containing hydrophobic functional group were characterized via swelling studies, Fourier transform infrared spectroscopy, elemental analysis, surface area measurements and scanning electron microscopy. DNA adsorption onto both p(HEMA‐MATrp) cryogel and p(HEMA‐MATrp)/p(HEMA) composite cryogels was investigated. Maximum adsorption of DNA on p(HEMA‐MATrp) cryogel was found to be 15 mg/g polymer. Otherwise, p(HEMA‐MATrp)/p(HEMA) composite cryogels significantly increased the DNA adsorption capacity to 38 mg/g polymer. Composite cryogels could be used repeatedly without significant loss on adsorption capacity after 10 repetitive adsorption–desorption cycles. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

13.
A novel, facile, and robust strategy was proposed to increase the pore size and mechanical strength of cryogels. By mixing the monomers of acrylamide and 2‐hydroxyethyl methacrylate as the precursor, a monolithic copolymer cryogel with large interconnected pores and thick pore walls was prepared. Hydrogen bonding between the two monomers contributed to the entanglement and aggregation of the copolymers, thickening the pore walls and resulting in larger pore sizes. Analysis via mercury porosimetry demonstrated that the interconnected pore diameter of the copolymer cryogel ranged from 10‐350 µm, which was far larger than that of the cryogels from one monomer (10‐50 µm). Additionally, the thicker pore walls of the copolymer cryogel improved its mechanical strength. Affinity cryogels were prepared through covalent immobilization using Tris(hydroxymethyl)aminomethane as a coupling agent, and the affinity binding of lysozymes on Tris‐cryogel was evaluated by the Langmuir isothermal adsorption with the maximum adsorption capacity of 360 mg/g. Compared with that of the Tris‐cryogels produced from one monomer, the copolymer Tris‐cryogel exhibited higher adsorption capacity and lysozyme purity, when the chicken egg white solution flowed solely driven by gravity. This work provides a new avenue for designing and developing supermacroporous cryogels for bioseparation.  相似文献   

14.
The surface‐grafting ion‐imprinting technology was applied to synthesis of a new Co(II)‐imprinted polymer [Co(II)‐IP], which could be used for selective removal of Co(II) from aqueous solutions. The prepared polymer was characterized by using the infrared spectra (IR), X‐ray diffractometer (XRD), X‐ray energy dispersion spectroscopy (EDS) and scanning electron microscopy (SEM). The maximum adsorption capacity values for the Co(II)‐imprinted polymer and non‐imprinted polymer (NIP) were 22 and 8 mg/g, respectively. The Freundlich equation fitted the adsorption isotherm data well. The applicability of two kinetic models including pseudo‐first‐order and pseudo‐second‐order models was estimated on the basis of comparative analysis of the corresponding rate parameters, equilibrium capacity, and correlation coefficients. Results suggested that chemical process could be the rate‐limiting step in the adsorption process. And the adsorption of Co(II) on the Co(II)‐imprinted polymer was endothermic. The relative selectivity coefficients of the Co(II)‐imprinted polymer for Co(II)/Pb(II), Co(II)/Cu(II), Co(II)/Ni(II), Co(II)/Sr(II) and Co(II)/Cs(I) were respectively 11.5, 6.1, 13.8, 9.4, and 8.1 times greater than that of the non‐imprinted polymer. Eventually, the desorption conditions of the adsorbed Co(II) from the Co(II)‐imprinted polymer were also studied in batch experiments.  相似文献   

15.
Recent years molecular imprinting has received considerable attention as an excellent and simple approach to recognize small molecules and bioactive substances. The aim of this study is to prepare the bilirubin-imprinted supermacroporous cryogels which can be used for the adsorption of bilirubin from human plasma. N-methacryloyl-(L)-tyrosinemethylester (MAT) was chosen as the pre-organization monomer. In the first step, bilirubin was complexed with MAT and the bilirubin-imprinted poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-tyrosine methylester) [BR-MIP] cryogel was produced by free radical polymerization initiated by N,N,N',N'-tetramethylene diamine (TEMED) and ammonium persulfate (APS) pair in an ice bath. After that, the template molecules (i.e., bilirubin) were removed from the polymeric structure using sodium carbonate and sodium hydroxide. The maximum bilirubin adsorption amount was 3.6 mg/g polymer. The relative selectivity coefficients of the BR-MIP cryogel for bilirubin/cholesterol and bilirubin/testosterone mixtures were 7.3 and 3.2 times greater than non-imprinted poly(HEMA-MAT) [NIP] cryogel, respectively. The BR-MIP cryogel could be used many times without decreasing bilirubin adsorption amount significantly. Therefore, as a reusable carrier possessing high selectivity, BR-MIP cryogel has a potential candidate as a clinical hemoperfusion material.  相似文献   

16.
Supermacroporous poly(2-hydroxyethyl methacrylate-co-1,5-naphthalene bismaleimide) [poly(HEMA-co-NBMI)] monolithic cryogel column was prepared by free radical cryo-copolymerization of HEMA with NBMI as a hydrophobic functional comonomer and N,N′-methylene-bisacrylamide as cross-linker directly in a plastic syringe for adsorption of albumin. The monolithic cryogel contained a continuous polymeric matrix which has interconnected pores of 10–100 μm size. Poly(HEMA-co-NBMI) cryogel was characterized by swelling studies, FTIR and scanning electron microscopy. The equilibrium swelling degree of the poly(HEMA-co-NBMI) cryogel was 10.5 g of H2O/g dry cryogel. Poly(HEMA-co-NBMI) cryogel was used in the adsorption/desorption of IgG from aqueous solutions. The maximum amount of IgG adsorption from aqueous solution in phosphate buffer was 98.20 mg/g polymer at pH 7.0. The nonspecific adsorption of IgG onto plain poly(HEMA) cryogel was very low (2.79 g/g polymer). It was observed that IgG could be repeatedly adsorbed and desorbed with the poly(HEMA-co-NBMI) cryogel without significant loss of adsorption capacity.  相似文献   

17.
以咖啡因作为模板分子,α-甲基丙烯酸为功能单体,乙二醇二甲基丙烯酸酯为交联剂,制备了咖啡因分子印迹聚合物(MIP)。与非印迹聚合物(NIP)相比,MIP对咖啡因具有更高的吸附容量和选择性,MIP和NIP对咖啡因的最大静态吸附量分别为28.1和16.5mg/g,相对选择因子为1.25。以咖啡因分子印迹聚合物为固相萃取填料,结合高效液相色谱(HPLC),建立了茶水中咖啡因浓度及人饮茶后血清中咖啡因浓度的检测方法。考察了洗脱剂种类和用量对咖啡因回收率的影响。当萃取柱依次以2mL水活化,水溶液上样,2mL水淋洗,6mL甲醇-乙酸(9∶1,V/V)洗脱,咖啡因在MIP固相萃取柱上的回收率达到97.5%,而在NIP柱上的回收率仅为54.9%。  相似文献   

18.
In the current work, a molecularly imprinted polymer (MIP) has been synthesised and used to enable the extraction of a naturally-occurring antioxidant from complex media. More specifically, we describe the first example of a caffeic acid (CA) MIP which has been synthesised in the form of well-defined polymer microspheres, and its use for the extraction of CA from fruit juice sample. The CA MIP was synthesised by precipitation polymerisation using 4-vinylpyridine as functional monomer, divinylbenzene-80 as crosslinker and acetonitrile:toluene (75/25, v/v) as porogen. The particle sizing and morphological characterisation of the polymers was carried out by means of scanning electron microscopy (narrow particle size distribution; ~5 and 1.5 μm particle diameters for the MIP and NIP [non-imprinted polymer], respectively) and nitrogen sorption porosimetry (specific surface areas of 340 and 350 m(2)g(-1), and specific pore volumes of 0.17 and 0.19 cm(3)g(-1) for the MIP and NIP, respectively). The polymers were evaluated further by batch rebinding experiments, and from the derived isotherms their binding capacity and binding strength were determined (number of binding sites (N(K))=0.6 and 0.3 mmol g(-1) for the MIP and NIP, respectively, and apparent average adsorption constant (K(N))=10.0 and 1.6L mmol(-1) for the MIP and NIP, respectively). To evaluate the molecular recognition character of the MIP it was packed into a stainless steel column (50 mm × 4.6 mm i.d.) and evaluated as an HPLC-stationary phase. The mobile phase composition, flow rate, and the elution profile were then optimised in order to improve the peak shape without negatively affecting the imprinting factor (IF). Very interesting, promising properties were revealed. The imprinting factor (IF) under the optimised conditions was 11.9. Finally, when the imprinted LC column was used for the selective recognition of CA over eight related compounds, very good selectivity was obtained. This outcome enabled the direct extraction of CA in commercial apple juice samples with recoveries in excess of 81% and, rather significantly, without any need for a clean-up step prior to the extraction.  相似文献   

19.
The surface imprinting technique has been developed to overcome the mass‐transfer difficulty, but the utilization ratio of template molecules in the imprinting procedure still remains a challengeable task to be improved. In this work, specifically designed surface‐imprinted microspheres were prepared by a template‐oriented method for enantioseparation of amlodipine besylate. Submicron mesoporous silica microspheres were surface‐modified with double bonds, followed by polymerizing methacrylic acid to generate carboxyl modified mesoporous silica microspheres (PMAA@SiO2). Afterwards, PMAA@SiO2 was densely adsorbed with (S )‐amlodipine molecules to immobilize template molecules through multiple hydrogen bonding interactions. Then surface molecular imprinting was carried out by cross‐linking the carboxyl group of PMAA@SiO2 with ethylene glycol diglycidyl ether. The surface‐imprinted microspheres showed fast binding kinetics of only 20 min for equilibrium adsorption, and the saturation adsorption capacity reached 137 mg/g. The imprinted materials displayed appreciable chiral separation ability when used as column chromatography for enantioseparation of amlodipine from amlodipine besylate, and the enantiomeric excess of (S )‐amlodipine reached 13.8% with only 2.3 cm column length by no extra chiral additives. Besides, the imprinted materials exhibited excellent reusability, and this allows the potential application for amplification production of amlodipine enantiomer.  相似文献   

20.
A 2-(3,4-dimethoxyphenyl)ethylamine imprinted polymer (MIP(pt) ) was prepared via the precipitation polymerization together with a nonimprinted polymer (NIP). The morphology of particles was investigated by scanning electron microscopy and the specific surface areas were estimated by methylene blue adsorption (60.5 ± 3.5 and 36.9 ± 1.2 m(2)/g for MIP(pt) and NIP, respectively). The binding experiments were performed to determine the binding capacity of MIP(pt)/NIP particles toward dopamine. Next, the effects of solvents on loading, washing, and eluting steps were examined on solid-phase extraction (SPE). Methanol-water 85:15 v/v (loading step), methanol (washing step), and 0.04 M aqueous ammonium acetate-methanol 30:70 v/v (eluting step) were selected as the most effective systems. Described SPE protocol was successfully applied for separation of dopamine on 2-(3,4-dimethoxyphenyl)ethylamine imprinted particles. Finally, the molecularly imprinted polymer was used for determination of dopamine in spiked banana extract. The total recovery of dopamine from MIP(pt) was equal to 88.5 ± 4.6%, but from NIP was only 12.8 ± 2.3%. The developed material and method were demonstrated to be applicable for the separation of dopamine from bananas. The commercial sorbent C18 was not suitable to such application.  相似文献   

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