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1.
Ultrathin films of molecularly imprinted polymer (MIP) were prepared by photoiniferter on PVC beads for the selective uptake of lysozyme, taken as a model protein. Acrylamide was selected as the functional monomer and N,N‐methylenebisacrylamide as the crosslinking agent. The copolymerization process was confined to the surface of the PVC beads grafted with diethyldithiocarbamate iniferter initiator in the presence of lysozyme. After extraction of lysozyme from the shell of the PVC‐MIP beads, the latter were then used as artificial receptors for the rebinding of lysozyme. The sequential steps of the modification of PVC beads were monitored by XPS, infrared and Raman spectroscopies. The imprinting step was found to be essential as the PVC‐MIP beads could recognize lysozyme but not the non‐imprinted beads (PVC‐NIP). The binding properties of PVC‐MIP beads were determined using UV spectroscopy from adsorption isotherms of lysozyme, cytochrome, and myoglobin. The imprinted beads were found to be highly selective toward lysozyme over the competitive proteins. This work shows the interest of photoiniferter as an efficient mean for the design of molecularly imprinted polymer beads for rapid, selective removal of proteins. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43694.  相似文献   

2.
A molecularly imprinted polymeric receptor for trypsin was synthesized by employing a novel technique that is a combination of affinity separation and molecular imprinting. An enzyme–inhibitor complex of trypsin and N‐acryloyl para‐aminobenzamidine was polymerized with acrylamide and N,N'‐methylene bis‐acrylamide. Template trypsin was extracted out to obtain an affinity‐imprinted polymer. Control experiments were performed to demonstrate the synergistic affinity‐imprinting effect. The percentage of crosslinker used was the crucial factor in determining the imprinting efficacy of the polymers. Imprinted polymer containing 50% crosslinker exhibited a linear Scatchard plot. Unlike non‐imprinted gel, the receptor exhibited almost exclusive recognition of trypsin in an individual batch experiment as well as from a mixture of trypsin and chymotrypsin. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1075–1083, 2001  相似文献   

3.
A safe and facile approach for the preparation of magnetic molecularly imprinted polymer nanospheres for 2,4,6‐trinitrotoluene (TNT) recognition is reported. The imprinted nanospheres were synthesized using TNT as the imprinting molecule, acrylamide as the functional monomer, N,N'‐methylenebisacrylamide as the crosslinker and magnetic particles as the support. The structure of the materials was identified via Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy and transmission electron microscopy. Static adsorbing experiments were carried out and Scatchard plot analysis showed that two kinds of receptor sites were formed in the imprinted materials. The adsorption equilibrium constant and the maximum adsorption capacity were evaluated. These results indicated that the imprinted nanospheres have higher adsorption capacity and selectivity for TNT than non‐imprinted polymer nanospheres with the same composition. © 2013 Society of Chemical Industry  相似文献   

4.
Tyrosine and phenylalanine imprinted Fe3O4/P(St‐DVB) composite beads with magnetic susceptibility were prepared by suspension polymerization using Fe3O4 as the magnetically susceptible component, methacrylic acid and acrylamide as functional monomers, styrene and divinylbenzene as polymeric matrix components, stearic acid as porogen, and poly(ethylene glycol) 4000 as dispersant. Scanning electron microscopy examination of the composite beads showed macropores on the surface of spherical beads. The diameters of the composite beads and the macropores were in the ranges ~ 400–450 and 4–20 μm, respectively. The average content of Fe3O4 inside the composite beads was 3.78%, and Fe3O4 was unevenly distributed. The mechanism of macropore formation and the concept of “intellectual cavity” of molecularly imprinted composite beads were proposed. The recognition selectivity of the composite beads was investigated using tyrosine and phenylalanine as both templates and comparative molecules. Tyrosine‐imprinted composite beads exhibited a good recognition selectivity for tyrosine, and the separation factor was up to 3.67. In contrast, phenylalanine‐imprinted composite beads had little recognition selectivity for phenylalanine and the separation factor was only 1.12. It was confirmed that the three‐site interaction between tyrosine and functional monomers was stronger than the two‐site interaction between phenylalanine and functional monomers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 3790–3796, 2003  相似文献   

5.
Molecularly imprinted polymer beads of bovine serum albumin (BSA) were prepared via inverse phase suspension polymerization, using BSA as the template molecule, a combination of acrylamide and methacrylic acid (MAA) as double functional monomers, and N, N′‐methylene bisacrylamide as the crosslinker. The effect of different monomer ratios and degrees of crosslinking were investigated. When both selectivity and physical properties of the resultant polymer beads were taken into account, the ratio of MAA in the total monomers was chosen at 40% (m/m) and the degree of crosslinking at 30% (n/n), the resultant polymer beads had good selectivity (α = 2.77) and good physical properties. The effects of pH and temperature were studied. It turned out that the functionalization of polymers of BSA prepared via inverse‐phase suspension polymerization exhibited specific recognition for BSA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

6.
Pickering emulsion polymerization was used to synthesize molecularly imprinted polymer beads for the selective recognition of 17‐β‐estradiol under aqueous conditions. Scanning electron microscopy analysis indicated that the imprinted polymer beads had a small diameter with a narrow size distribution (18.9 ± 2.3 μm). The reduction in particle size achieved in this study was attributed to the altered polarity of the stabilizing nanoparticles used in the Pickering emulsion. The imprinted polymer beads could be used directly in water and showed a high binding affinity for the template molecule, 17‐β‐estradiol, and its structural analogs. These water‐compatible polymer beads could be used as affinity adsorbents for the extraction and analysis of low‐abundance steroid compounds in aqueous samples. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39606.  相似文献   

7.
An azobenzene‐containing molecularly imprinting polymer microsphere with photoresponsive binding properties toward 2,4‐dichlorophenoxyacetic acid (2,4‐D) was successful prepared via silica surface polymerization. The number‐average diameters of silica and imprinting polymer microsphere are 0.5 and 0.7 μm, respectively. The static adsorption, binding and selectivity experiments were performed to investigate the adsorption properties and recognition characteristics of the polymers for 2,4‐D. The equilibrium adsorptive experiments indicated that 2,4‐D‐SMIP(surface molecularly imprinted polymers) has significantly higher adsorption capacity for 2,4‐D than its nonimprinted polymers (SNIP).The binding constant Kd and apparent maximum number Qmax of the imprinted polymer were determined by Scatchard analysis as 0.054 mmol L?1 and 0.167 mmol g?1, respectively. The result of photoregulated release and uptake of 2,4‐D experiment demonstrated that azo‐containing SMIP can make use of light and change it into mechanical properties to release and take up the template molecules. It means that the SMIP can be controlled by light. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 869‐876, 2013  相似文献   

8.
Quercetin is an important compound of flavonoids. In this work, quercetin molecule surface‐imprinted material with high performance was prepared using a novel surface‐imprinting technique of “synchronously graft‐polymerizing and imprinting.” The modified micron‐sized silica gel particles containing amino groups were used as matrix, methacrylic acid (MAA) was used as functional monomer, and N,N′‐Methylenebisacrylamide (MBA) was used as crosslinker. In dimethyl formamide solution of quercetin, MAA molecules arranged automatically around the template quercetin molecule by right of hydrogen bonding interactions of two type, ordinary hydrogen bond and π‐type hydrogen bond. By initiating the surface‐initiating system of – , the graft/cross‐linking polymerization of MAA on SiO2 particles and the quercetin molecule surface‐imprinting were simultaneously carried out, forming quercetin molecule surface‐imprinted material MIP‐PMAA/SiO2. With another two flavonoids, rutin and genistein, as contrasting substances, the molecule recognition character of the quercetin molecule surface‐imprinted material MIP‐PMAA/SiO2 was investigated with batch and column methods. The experimental results show that the imprinted material MIP‐PMAA/SiO2 possesses special recognition selectivity and excellent binding affinity for quercetin molecule. The binding capacity of MIP‐PMAA/SiO2 for quercetin is 0.325 mmol/g, and its selectivity coefficients for quercetin relative to rutin and genistein are 7.69 and 4.40, respectively. The main conditions of imprinting process affect the property of MIP‐PMAA/SiO2 greatly, and the optimal molar ratio of monomer MAA to crosslinker MBA is 7 : 1 and appropriate molar ratio of monomer MAA to template quercetin is equal to 6 : 1. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41112.  相似文献   

9.
The particle size of N‐halamine biocidal polymers was methodically modified forming beads of different sizes by blending water‐insoluble N‐halamine polyurethane with sodium alginate as the matrix and loading heterocyclic rings onto modified silica gels. The biological activity of the prepared beads and halogenated modified silica derivatives was evaluated against examples of Gram‐positive (Staphylococcus aureus) and Gram‐negative (Escherichia coli) bacteria. The recycling possibilities and the optimum preparation conditions of the blended beads were investigated; blending prehalogenated polyurethane (5%, w/v) with sodium alginate (3%, w/v) followed by crosslinking with CaCl2 (10%, w/v) at 40°C are the optimum preparation conditions for the alginate beads. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

10.
Photoresponsive polymer with azobenzene pendant group (PDMAA‐co‐PAPA) was synthesized by radical polymerization of N,N‐dimethylacrylamide (DMAA) and N‐4‐phenylazophenyl acrylamide (PAPA), and the characterization of the inclusion complexes of the PDMAA‐co‐PAPA with α‐cyclodextrin (α‐CD) were performed by FTIR, GPC, 1H NMR, 2D NOESY, and UV–vis spectroscopy. It was found that the solubility of PDMAA‐co‐PAPA and α‐CD inclusion complexes in aqueous solution showed tunable property, which could be triggered by alternating UV–vis light irradiation at a certain temperature due to the effect of molecular recognition of α‐CD with azobenzene moiety in the polymer. After UV irradiation, the lower critical solution temperature (LCST) of the polymer aqueous solution increased slightly without α‐CD while the LCST decreased sharply at presence of α‐CD. Furthermore, UV spectroscopy showed that the photoisomerization of the polymer solution went on rapidly and reversibly, and 2D NOESY data suggested that the inclusion complexation of α‐CD with trans azobenzene moiety and the decomplexation with cis azobenzene resulted in reversible solubility behavior when objected to UV and Vis light irradiation alternately. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

11.
Molecularly imprinted polymers are being proposed for the development of novel biorecognition elements for active components. In this study, an imprinted chitosan coated silica nanoparticles (I‐CS@SiO2) polymer was prepared by a simple procedure, in which, naringin (NG) with antioxidant activity, acted as a template, silica as a matrix and CS as a functional polymer. The binding properties were discussed by the equilibrium binding experiment method. Experiments show that the adsorption characteristics of I‐CS@SiO2 are better than that of nonimprinted polymer. It exhibited high selectivity for NG when compared with the nonimprinted polymer, with an imprinting factor α of 1.74. Scatchard analysis of the I‐CS@SiO2 indicated that there was a class of binding sites during the I‐CS@SiO2 recognizing NG: The dissociation constant of KD is 0.016 mmol L?1, the maximum apparent binding capacity of Bmax is 6.56 μmol g?1. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40491.  相似文献   

12.
Preparation of interpenetrating polymer network (IPN) gel beads for dye absorption was carried out by using simultaneous crosslinking method. First, sodium alginate (SA), 3‐(methacrylamido) propyl trimethyl ammonium chloride (MAPTAC), and/or acrylamide (AM), K2S2O8, and N,N′‐methylenebisacrylamide (MBAM) were mixed in aqueous solution. The beads were prepared using K2S2O8 and MBAM as the initiator and crosslinking agent, respectively. Then, the solution was dropped into CaCl2 solution mixed with N,N,N′,N′‐tetramethylethylenediamine (TMEDA). The former was used as the crosslinking agent of alginate and the latter was used as the accelerator for the polymerization of monomer in the alginate solution. The gel bead composed of only alginate was also prepared to compare the properties with IPN gel bead. The components in IPN gel bead were examined by FTIR analysis. The factors effecting the particle size of alginate and IPN gel beads were investigated. In alginate gel bead, the concentration of solution affected the particle size, whereas type of monomer affected the particle size of IPN gel bead. The IPN gel bead had smooth surface (from SEM results), different from the alginate bead. Alginate content caused the swelling behavior of dried IPN beads. Cationic dye was absorbed by crosslinked alginate gel bead. The absorption of reactive dye by IPN gel bead was a result of its cationic charge. The absorption density of IPN gel beads was the reciprocal of the absorbent dosage. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1585–1591, 2006  相似文献   

13.
p-Nitrophenol is a hazardous phenolic compound and its separation and determination is very necessary to protect public health and environmental quality. In this article, macromolecule polyethyleneimine (PEI) grafted on the surface of silica particles was crosslinked using p-nitrophenol as a template and diepoxyalkyl (669) as a crosslinking agent, and molecularly imprinted polymer on the surfaces of silica gel MIP-PEI/SiO2 was prepared. The binding and recognition ability of MIP-PEI/SiO2 for p-nitrophenol were researched using batch and dynamic methods. The experimental results showed that MIP-PEI/SiO2 had high affinity, specific recognition ability, and excellent selectivity for p-nitrophenol. The saturated binding amount could reach to 155.5 mg g−1. The selectivity coefficients relative to m-nitrophenol and chlorophenol were 45.80 and 117.5, respectively. The empirical Freundlich isotherm was found to describe well the equilibrium binding data. pH of sample solution was found to have a strong influence on the binding amount. MIP-PEI/SiO2 was regenerated easily using diluted hydrochloric acid solution as eluent and MIP-PEI/SiO2 possesses better reusability. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012  相似文献   

14.
Four different copolymers, of acrylamide and acrylic acid, acrylamide and 2‐acrylamido‐2‐methyl propane sulfonic acid, N,N‐dimethylacrylamide and acrylic acid, and N,N‐dimethylacrylamide and 2‐acrylamido‐2‐methyl propane sulfonic acid (sodium salts), were prepared. The copolymers were characterized by their intrinsic viscosities and monomer ratios and with IR, 1H‐NMR, and X‐ray diffraction (XRD) spectroscopy. No crystallinity was observed by differential thermal analysis, and this was well supported by XRD. All the polymers showed low decomposition temperatures. A number of decomposition temperatures were observed in differential thermogravimetry thermograms because of the elimination of gases such as CO2, SO2, CO, and NH3. The replacement of the acrylate group with a sulfonate group produced polymers that were more compatible with brine, whereas the replacement of acrylamide with a more hydrophobic group such as N,N‐dimethylacrylamide produced a more shear‐resistant polymer. A N,N‐dimethylacrylamide‐co‐sodium‐2‐acrylamido‐2‐methyl propane sulfonate copolymer was better with respect to thermal stability when the polymer solution was aged at 120°C for a period of 1 month. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1869–1878, 2003  相似文献   

15.
Two clozapine (CLZ) imprinted polymers were prepared by bulk and precipitation methods. Methacrylic acid and ethylene glycol dimethacrylate (EDMA) were used as functional and crosslinker monomers, respectively. The mean diameter and particle size distribution of the imprinted (P‐MIP) and nonimprinted (P‐NIP) particles obtained in precipitation method were examined. A conventional batch‐adsorption test was applied for characterization of CLZ–polymer interaction. Dissociation constant (KD) and maximum binding sites (Bmax) were calculated using Scatchard analysis. To evaluate the recognition properties of polymers, phenytoin (PTN) binding to each polymer was also studied and compared to CLZ. The imprinting factor (IF) and selectivity factor (α) were also determined for each polymer. Average diameter and polydispersity of P‐MIP were 925 nm and 0.17, respectively. The data for P‐NIP were 1.05 μm and 0.18. The KD, IF, and α values calculated for P‐MIP were 0.45 μM, 3.26, and 17.43, respectively. The data for imprinted polymer, prepared by bulk polymerization (B‐MIP), were 14.5 μM, 1.95, and 3.67. These results demonstrated that precipitation polymerization is a more convenient, more effective, and more reproducible method than bulk polymerization for the synthesis of uniformly sized micron and submicron‐imprinted polymer particles. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

16.
We used a molecular imprinting approach to achieve specific metal binding utilizing N‐methacryloyl‐(L )‐cysteine methyl ester (MAC) as a metal‐complexing ligand. MAC was synthesized using methacryloyl chloride and cysteine methyl ester. Then, Fe3+ was complexed with MAC monomer. Fe3+‐imprinted poly(hydroxyethyl methacrylate‐N‐methacryloyl‐(L )‐cysteine methyl ester) [poly(HEMA‐MAC)] beads with average size of 63–140 μm were produced by suspension polymerization. After that, the template ions (i.e. Fe3+ ions) were removed by 0.1M HCl. Fe3+‐imprinted beads were characterized by swelling studies, FTIR, and elemental analysis. The Fe3+‐imprinted beads with a swelling ratio of 72%, and containing 3.9 mmol MAC/g were used in the binding of Fe3+ ions from aqueous solutions, tap water, certified reference serum sample, and real serum sample. Maximum binding capacity, optimum pH, and equilibrium binding time were 107 μmol/g, pH 3.0, and 30 min, respectively. It was observed that even in the presence of other ions, Fe3+‐imprinted beads selectively bound Fe3+ ions with 97% efficiency. Removal of Fe3+ ions from certified reference serum sample was approximately found to be 33%. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3520–3528, 2006  相似文献   

17.
Ni2+‐imprinted monolithic column was prepared for the removal of nickel ions from aqueous solutions. N‐Methacryloyl‐L ‐histidine was used as a complexing monomer for Ni2+ ions in the preparation of the Ni2+‐imprinted monolithic column. The Ni2+‐imprinted poly(hydroxyethyl methacrylate‐N‐methacryloyl‐L ‐histidine) (PHEMAH) monolithic column was synthesized by bulk polymerization. The template ion (Ni2+) was removed with a 4‐(2‐pyridylazo) resorcinol (PAR):NH3? NH4Cl solution. The water‐uptake ratio of the PHEMAH–Ni2+ monolith increased compared with PHEMAH because of the formation of nickel‐ion cavities in the polymer structure. The adsorption of Ni2+ ions on both the PHEMAH–Ni2+ and PHEMAH monoliths were studied. The maximum adsorption capacity was 0.211 mg/g for the PHEMAH–Ni2+ monolith. Fe3+, Cu2+, and Zn2+ ions were used as competitive species in the selectivity experiments. The PHEMAH–Ni2+ monolithic column was 268.8, 25.5, and 10.4 times more selective than the PHEMAH monolithic column for the Zn2+, Cu2+, and Fe3+ ions, respectively. The PHEMAH–Ni2+ monolithic column could be used repeatedly without a decrease in the Ni2+ adsorption capacity. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

18.
Protein‐imprinted soft‐gel composite microspheres with magnetic susceptibility (MS‐PIGMs) were prepared by inverse suspension polymerization using Fe3O4 particles as magnetically susceptible component and bovine serum albumin and lysozyme (Lyz) as templates, respectively. The average content of magnetically susceptible component (Fe3O4) inside MS‐PIGMs was determined using thermogravimetric analyzer, and the magnetic characteristics of MS‐PIGMs were measured by vibrating sample magnetometer. The results showed that the resulting MS‐PIGMs had a certain magnetic response to external magnetic fields, and their average content of Fe3O4 was 2.08%. Their recognition specificity was investigated using BSA and Lyz as both templates and control molecules and characterized by high‐performance liquid chromatography, and the mechanism of imprinting and recognition was analyzed. It was shown that the resulting BSA imprinted soft‐gel composite microspheres with magnetic susceptibility (BSA‐PIGMs) and Lyz imprinted soft‐gel composite microspheres with magnetic susceptibility (Lyz‐PIGMs). All exhibited good recognition selectivity for their templates, and the relative separation factor (β) was 4.75 and 5.88, respectively. The recognition selectivity of MS‐PIGMs to their templates depended mainly on the synergic action of a large quantity of hydrogen binding being caused by complementation and very close contact of outer surface of proteins with inner surface of “imprinting cavities.” © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006  相似文献   

19.
A Fe(III) ion‐imprinted silica gel polymer functionalized with phosphonic acid groups (IIP‐PA/SiO2) was prepared with surface imprinting technique by using Fe(III) ion as template ion, grafted silica gel as support, and vinylphosphonic acid as functional monomer. The polymer was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, Brunauer–Emmett–Teller, and thermogravimetric analysis. The synthesized imprinted silica gel polymer was used as a sorbent for Fe(III) adsorption. The adsorption properties, such as the effect of solution pH, adsorption kinetic, adsorption isotherm, adsorption selectivity as well as the regeneration of sorbent were studied. The results showd that the prepared sorbent (IIP‐PA/SiO2) had a short adsorption equilibrium time (12 min) and high adsorption capacity (29.92 mg g?1) for Fe(III) at the optimal pH of 2.0. The selectivity coefficients of the sorbent for Fe(III) in presence of Cr(III), Mn (II), and Zn(II) were 51.76, 27.86, and 207. 76, respectively. Moreover, the adsorption capacity of the prepared sorbent did not decrease significantly after six repeated use. Thus, the prepared ion‐imprinted silica gel polymer was a promising candidate sorbent for the selective adsorption of Fe(III) from aqueous solutions. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45165.  相似文献   

20.
A new and facile technique for preparing homogeneous and highly selective molecularly imprinted polymers (MIPs) films on porous monodisperse poly‐(glycidyl methacrylate‐co‐ethylene glycol dimethacrylate) beads (PGMA‐EDMA beads) has been described: before polymerization, initiator was immobilized on the PGMA‐EDMA beads' surface by chemical reactivity; then functional monomers and crosslinkers were initiated by the surface‐bound initiator and copolymerized to form MIPs films on the PGMA‐EDMA beads' surface in the presence of template molecules. The resulting beads were analyzed by FTIR spectroscopy and X‐ray photoelectron spectra. The effects of the initiator amount and copolymerization time on the content of MIPs, and MIPs contents on morphologies and pore properties of the resulting beads were investigated. The results show that the content of MIPs can be adjusted by changing initiator amount or by controlling copolymerization time. The binding experiments indicate that, at lower grafting level, with the increase of MIPs content, the adsorption and recognition capabilities of the resulting beads enhance. When MIPs content increase to 16.75%, the highest adsorption and recognition capabilities are obtained. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   

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