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1.
Inspired from the highly bioadhesive performance of mussel protein, a simple, yet efficient synthetic method for efficiently imprinting of Artemisinin (Ars) was developed to prepare the bio‐inspired molecularly imprinted membranes (MIMs) via atom transfer radical polymerization (ATRP). In this work, attributed to the unique properties of polydopamine (pDA) modified layers and ATRP technology, the uniform recognition sites for efficiently selective extraction of the Ars with high stability could be obtained on the MIMs surfaces. In addition, the maximum adsorption capacity of the MIMs is 158.85 mg g?1 by the Langmuir isotherm model, which is remarkable higher than NIMs. Additionally, because of the formation of the uniform specific recognition cavities on membrane surfaces, the as‐prepared MIMs exhibited a rapid adsorption dynamics and well‐fitted for the pseudo‐second‐order rate equation, also, possessed an excellent per‐selectivity performance (βartemether/Ars values is 0.18) of template molecule, which clearly demonstrated the potential value of this method in the selective separation and purification of Ars. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43405.  相似文献   

2.
BACKGROUND: There are few reports on erythromycin molecularly imprinted polymers (MIPs) used as HPLC stationary phase and solid phase extraction matrices. These imprinted polymers are prepared by bulk polymerization, which is tedious and time‐consuming, and they are irregular and possess poor reproducibility and low binding capacity. In this study, molecularly imprinted microspheres for erythromycin were prepared by aqueous suspension polymerization for the first time. RESULTS: Imprinted microspheres for erythromycin were prepared using suspension polymerization in which 1.5% PVA‐water solution is used as continuous phase, and chloroform solution containing erythromycin, methacrylic acid and crosslinker is used as disperse phase. The composition of disperse phase is optimized, and the optimum molar ratio of erythromycin to methacrylic acid was 1:5. Selectivity analysis revealed that the imprinted microspheres can specifically recognize erythromycin from its structure analogues. The binding mechanism between erythromycin and methacrylic acid was investigated by UV‐Vis spectrophotometry. Adsorption kinetics and the adsorption isotherm of the imprinted microspheres indicate that erythromycin can be adsorbed rapidly by the imprinted microspheres and the maximum theoretical static binding capacity is 128.6110 mg g?1. The imprinted microspheres were used to extract erythromycin from a milk sample and a high recovery rate was obtained. CONCLUSION: Molecularly imprinted microspheres for erythromycin were uniform and possess high adsorption capacity and excellent selectivity. They are therefore a promising extraction and chromatographic media. Copyright © 2011 Society of Chemical Industry  相似文献   

3.
Highly selective, ordered microporous molecularly imprinted membranes (MIMs) for phenol were synthesized by breath figure (BF) method using styrene‐acrylonitrile copolymer (SAN) as the membrane matrix and molecularly imprinted polymer nanoparticles (nano‐MIPs) as the imprinted nanoparticles. The nano‐MIPs were synthesized by oil‐in‐water emulsion polymerization using 4‐vinyl pyridine (4‐VP), methyl methacrylate (MMA) or cinnamic acid (CA) as the functional monomer, respectively. The prepared nano‐MIPs were characterized by transmission electron microscope (TEM) and Raman, whereas MIMs were characterized by SEM, membrane flux, and selective adsorption experiments. Morphological analysis exhibited that the addition of nano‐MIPs improved the formation of ordered and well‐defined porous membrane morphology. Compared with MMA‐MIM and CA‐MIM, the 4‐VP‐MIM exhibited higher membrane flux, adsorption capacity, and stronger selective binding for phenol as well as excellent permeation selectivity for phenol. Moreover, the selective effect of 4‐VP‐MIM on phenol was strongly affected by the amount of 4‐VP imprinted nanoparticles (nano‐4‐VP‐MIPs). The experimental data revealed that the 4‐VP‐MIM containing 2.0 wt % of nano‐4‐VP‐MIPs exhibited the highest separation selectivity for the template phenol, whose selectivity coefficients for phenol relative to salicylic acid (SA) and p‐hydroxybenzoic acid (p‐HB) were 5.6770 and 5.5433, respectively, which was close to the predicted selectivity coefficient value. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42350.  相似文献   

4.
Thermosensitive magnetic surface molecularly imprinted polymer microspheres based on thermosensitive monomer n ‐isopropylacrylamide (NIPAM) are applied for the recognition of 5‐fluorouracil (5‐FU). A computational analysis is used to predict the interaction sites between 5‐FU and NIPAM, the stoichiometry of the synthesis procedure, and the affinity of imprinted cavities toward 5‐FU. Due to hydrogen bond interactions, a stable complex configuration of 5‐FU and NIPAM shows a binding energy of ?46.50 kJ/mol confirming the suitability of imprinting 5‐FU into thermosensitive polymer network. After optimization, the appropriate stoichiometry of 5‐FU to NIPAM is set to 1:4 during the preparation process. The simulated imprinted cavities show affinity toward 5‐FU, with a binding energy of ?112.24 kJ/mol. A preliminary experimental evaluation for the drug recognition of thermosensitive magnetic surface molecularly imprinted polymer microspheres is made, obtaining an adsorption capacity of 21.72 mg/g at 25 °C. Pseudo‐second‐order kinetics well describes the adsorption process. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45468.  相似文献   

5.
A novel molecularly imprinted electrochemical sensor was developed for the sensitive and selective determination of ampicillin (AMP). The sensor was prepared on a platinum electrode modified with multiwalled carbon nanotubes (MWCNTs), gold nanoparticles (AuNPs), and a thin film of molecularly imprinted polymers (MIPs). MWCNTs and AuNPs were introduced to enhance the sensor's electronic transmission and sensitivity. The molecularly imprinted polymer (MIP) was synthesized using AMP as the template molecule, methacrylic acid as functional monomer, and ethylene glycol maleic rosinate acrylate (EGMRA) as cross‐linker. The performance of the proposed imprinted sensor was investigated using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The results showed that the imprinted film displayed a fast and sensitive response to AMP. Under optimal conditions, response peak current had a linear relationship with the concentration of AMP in the range of 1.0 × 10?8 mol/L to 5.0 × 10?6 mol/L and a detection limit of 1.0 × 10?9 mol/L (S/N = 3). This imprinted sensor was used to detect AMP in food samples with recoveries of 91.4–105%. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40613.  相似文献   

6.
A novel method for combinatorial synthesis and screening of uniform‐size molecularly imprinted microspheres using a microfluidic device is presented, in which a new microfluidic device containing twelve pairs of “” shape microchannels is designed to produce droplets and imprinted microspheres via controlled suspension polymerization. This technique combines molecular imprinting and microfluidic device with the combinatorial chemical approach, allowing rapid screening and optimization of uniform imprinted microspheres. On the example of chloramphenicol (CAP), the imprinted microspheres of CAP were prepared by a combinatorial approach using water with 1.5% polyvinyl alcohol as continuous phase, and ethyl acetate–chloroform (4:1, v/v) as porogenic solvents. Functional monomers methacrylic acid (MAA), 4‐vinylpyridine or acrylamide were screened, and the molar ratio of template molecule to functional monomer was optimized. The results indicate that MAA is the best functional monomer for imprinting of CAP, and when the molar ratio of CAP to MAA is 1:5, the imprinted microspheres exhibit the best imprinting performance, and have good monodispersity and selectivity. This combinatorial protocol is well suited for fast and efficient screening and optimization of synthesis for uniform imprinted microspheres because 12 kinds of imprinting conditions can be performed simultaneously in this microfluidic device. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers  相似文献   

7.
Macromolecularly imprinted calcium phosphate/alginate hybrid polymer microspheres surface imprinted with bovine serum albumin were prepared in inverse‐phase suspension by introducing the intermixture solutions of bovine serum albumin (BSA) and CaCl2 in sodium alginate aqueous solution where (NH4)2HPO4 was added beforehand. Morphology of the imprinted microspheres was observed by optical microscopy. Rebinding dynamic and thermodynamic behaviors of surface molecularly imprinted calcium phosphate/alginate polymer microspheres (CP/A SMIPMs) and embedding molecularly imprinted calcium phosphate/alginate polymer microspheres (CP/A EMIPMs) were evaluated. CP/A SMIPMs exhibited significant improvement in equilibrium rebinding capacity (Qe) and imprinting efficiency (IE), compared to CP/A EMIPMs. The surface of CP/A SMIPMs was more competent to facilitate the migration and re‐assembling of proteins. Surface specific peak and interior specific peak were proposed to describe the characteristics of surface and interior specific rebinding behaviors in rebinding dynamics. The effects of (NH4)2HPO4 addition were investigated in detail, along with the concentration of sodium alginate and CaCl2 solutions to the rebinding and imprinting property of imprinted microspheres. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   

8.
Water‐compatible molecularly imprinted polymers (MIPs) for caffeine were synthesized in aqueous medium with a new functional monomer, 1‐(α‐methyl acrylate)‐3‐methylimidazolium bromide (1‐MA‐3MI‐Br), which had π–π and hydrogen‐bonding interactions. Caffeine‐imprinted polymers were prepared in suspension polymerization with 1‐MA‐3MI‐Br and methacrylic acid (MAA), which only had hydrogen bonding, as a functional monomer. For the specific binding characteristics of the new functional monomer 1‐MA‐3MI‐Br, the adsorption capacity and relative separation factor (β) of MIPs for caffeine were significantly enhanced. The maximum adsorption capacities of 1‐MA‐3MI‐Br–MIP and MAA–MIP imprinted microspheres for caffeine were 53.80 and 28.90 μmol/g, respectively. Moreover, the relative separation factors were measured by comparison of the separation characteristics under competitive adsorption conditions. The results showed that the β of MAA–MIP for caffeine relative to theophylline was only 1.65; this showed a very poor recognition selectivity for caffeine, but β of 1‐MA‐3MI‐Br–MIP for caffeine with respect to theophylline was remarkably enhanced to 3.19; this showed an excellent recognition selectivity and binding affinity toward caffeine molecules in an aqueous environment. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   

9.
采用反相高效液相色谱-蒸发光散射监测器(RP-HPLC-ELSD)测定附子地上部分中新乌头碱和次乌头碱的含量。色谱柱为Krom asil C18(150 mm×4.6 mm,5μm),流动相为乙腈-0.1%乙二胺水溶液(体积比为60∶40),柱温为室温,流速1 mL/m in,漂移管温度89.0℃,气体流量2.60 L/m in。结果表明,新乌头碱和次乌头碱均得到较好分离,均在12.5~400μg/mL呈现良好的线性关系;平均加样回收率分别为100.01%(RSD=0.31%),99.53%(RSD=0.51%)。RP-HPLC-ELSD法具有准确度高,简便快捷,干扰少,重现性好的优点,可用于附子地上部分中双酯型生物碱的测定。  相似文献   

10.
This work describes the preparation of molecularly imprinted polymers using ZnO quantum dots, which were used for the selective detection of diethylhexyl phthalate (DEHP). Methacrylic acid, ethylene glycol dimethacrylate, 2,2′‐azobis(2‐methylpropionitrile) and ZnO were used as functional monomer, crosslinker, initiator and optical material, respectively. Molecularly imprinted polymers were successfully synthesized, and the linear relationship between fluorescence intensity and amount was from 0.5 to 40 µmol L?1 for DEHP. The coefficient of correlation was 0.9923 and the imprinting factor was 11.16. The results were above 97.50% and relative standard deviation below 3.86% for the detection of DEPH in actual water samples. This study could provide a novel method using molecularly imprinted polymers for highly selective and sensitive detection of DEHP. © 2018 Society of Chemical Industry  相似文献   

11.
Polyethylene glycol grafted calcium alginate hydrogel microspheres are synthesized by ring‐opening and addition reaction of epoxy chloropropane. FTIR, 13C NMR, optical microscope, SEM, TG, and DSC are used for characterization. Swelling behaviors are studied and it is found that polyethylene glycol grafted calcium alginate microspheres are improved in anti‐swelling properties. Protein‐imprinted polyethylene glycol grafted calcium alginate hydrogel microspheres exhibit enhanced specific rebinding quantity (11.16 mg/g) and selective recognition properties (4.71 against BHb), towards target molecule in the presence of competing protein, compared with that of the unmodified samples (4.96 mg/g and 1.75, respectively). © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43617.  相似文献   

12.
The aim of this study is to prepare flavone imprinted silica with good sphericity. Previous studies have demonstrated that imprinted silica can be synthesized using a simple sol‐gel method and a grinding‐sieving process. Despite the simplicity of the synthetic method, the appearance of the final product obtained is often very irregular and nonuniform. This product has many utilization issues and problems, e.g., residues and low operability. In this study, one type of novel spherical flavone imprinted silica was synthesized. A sol‐gel method and molecular imprinting technique were employed. By using luteolin as a template molecule, aminopropyltriethoxysilane (APTS) as the functional monomer, tetraethoxysilane (TEOS) as the cross‐linking agent, molecularly imprinted silica microspheres were prepared via a two‐stage reaction. The preparation conditions were monitored by the appearance of the products. SEM images show that under optimum conditions, the diameters of these microspheres are ca. 20–30 μm. The amino group adsorption peaks can be seen from the IR spectra. Results from elemental analysis indicate that 3.206 μmol of amino groups were successfully introduced into 1 g of product. This microspheric adsorbent has a high adsorption capacity to the template molecule, high adsorption selectivity and reproducibility. The adsorption capacity amounted to 32.987 mg/g and the separation factor was up to 84.3, while the adsorption capacity hardly decreased after 15 cycles.  相似文献   

13.
Using tribenuron‐methyl as a template and N,O‐bismethacryloyl ethanolamine as a functional crosslinking monomer, a molecularly imprinted nanowire membrane was prepared over an anodic alumina oxide membrane. The nanowire fabric of the imprinted membrane was established with a scanning electron microscope and a transmission electron microscope. However, the nonimprinted particulate membrane is formed in the absence of a template. Scatchard analysis showed that an equal class of binding sites were formed in the imprinted nanowire membrane and the dissociation constant and the maximum number of these binding sites were estimated to be 1.44 × 10−5 M and 22.7 µmol/g, respectively. The permeation experiments throughout the imprinted membrane and the nonimprinted one were carried out in a solution containing the template and its competitive analogs. These results demonstrated that the molecularly imprinted nanowire membrane exhibited higher transport selectivity for the template tribenuron‐methyl than its analogs, chlorimuron‐ethyl, thifensulfuron‐methyl and N‐(4‐bromophenylcarbamoyl)‐5‐chloro‐1H‐benzo[d]imidazole‐2‐carboxamide. But the nonimprinted granular membrane had no permselectivity for the four substrates. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

14.
To obtain the desired specific adsorbents for monocrotophos (MCP) to enrichment, separation, and analysis of trace pesticides residue in soils and foods, molecularly imprinted polymer microspheres were prepared by precipitation polymerization using MCP, methacylic acid (MAA), ethylene glycol dimethacrylate, azobisisobutyronitrile, and toluene as template, functional monomer, crosslinker, initiator, and porogen, respectively. Computer simulation was employed to demonstrate the mechanism of the interaction between MCP and MAA in toluene. It was found that one MCP was entrapped by two MAAs in toluene through hydrogen bond. The binding properties of MCP in toluene for imprinted microspheres were evaluated by equilibrium rebinding experiments. Scatchard plot analysis revealed that there were two classes of binding sites populated in the imprinted polymer microspheres with dissociation constants of 0.0019 and 0.12 mmol/L, respectively. The specificity of the imprinted microspheres was investigated by binding analysis using MCP and structurally related organophosphorous pesticides. The results indicated that the obtained imprinted microspheres showed a good selectivity for MCP. POLYM. ENG. SCI., 47:1302–1308, 2007. © 2007 Society of Plastics Engineers  相似文献   

15.
This study focus on the effect of the porogenic solvent on the morphology, recognition, and drug release of carbamazepine‐molecularly imprinted polymer nanospheres prepared by precipitation polymerization. The scanning electron microscopy (SEM) images and Brunauer‐Emmett‐Teller (BET) analysis showed that molecularly imprinted polymer (MIP) prepared by acetonitrile exhibited a regular spherical shape at the nanoscale with a high degree of monodispersity, specific surface area of 242 m2 g−1, and pore volume of 1 mL g−1, while those using chloroform and toluene produced irregular polymer particles with low specific surface area and pore volume. MIP prepared by acetonitrile/chloroform (1 : 1, v/v) showed mediator texture properties compared to MIPs obtained by acetonitrile or chloroform. Results from saturation and displacement assays indicated that the imprinted nanospheres with binding capacity of 2.85 (mg CBZ/g polymer) had high specific affinity to CBZ in contrast to nonimprinted nanospheres (1.63 mg CBZ/g polymer). The imprinted nanospheres with 2.4 selectivity factor had good recognition to CBZ than analog template of oxcarbazepine. Moreover, release studies showed that 20% of loaded CBZ was released from the imprinted nanospheres within the initial 6 h, while another 80% of CBZ was released in the following 9 days. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

16.
Molecularly imprinted polymeric membranes were prepared from cellulose acetate (CA), of which acetyl content was 40%, by applying the alternative molecular imprinting technique. The Z‐d ‐Glu imprinted polymeric membranes thus obtained recognized d ‐Glu in preference to l ‐Glu from racemic Glu mixtures and vice versa. The affinity constants between Glu and the chiral recognition site for two kinds of membranes were determined to be 3.1 × 103 mol−1 dm3 from the adsorption isotherm of d ‐Glu or L ‐Glu in the molecularly imprinted CA membranes. Enantioselective electrodialysis was attained with the present membranes reflecting their adsorption selectivity. d ‐Glu was preferentially permeated through the Z‐d ‐Glu imprinted CA membrane, whereas L ‐Glu was permeated through the Z‐L ‐Glu imprinted CA membrane. The present study suggests that the molecularly imprinted CA membranes are applicable to the optical resolution of racemic amino acids. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 493–499, 1999  相似文献   

17.
The rebinding behavior of protein‐imprinted hydrogel is different from classical small molecularly imprinted polymer especially in protein aggregating state and interaction changeability between protein and imprinted sites. BSA‐imprinted calcium alginate‐hydroxy ethyl cellulose microspheres were prepared, and the rebinding behavior was studied. An “imprinting induce‐fit model” was proposed to describe the rebinding property of protein‐imprinted hydrogel. Three kinds of different interacting forms between protein and imprinted hydrogel were discovered by Scatchard analysis. Slogistic fit analysis of rebinding rate coefficient was carried out, and the imprinted hydrogel was found capable of promoting rebinding through induce‐fit behavior. Higher imprinting efficiency was found in microsphere samples with lower crosslinking density. Rebinding regression equation was established, and the rebinding quantity was computable with parameters including BSA aggregate concentration [Pn], dissociating rate (k1), and single molecule rebinding rate (k2). The experimental and calculated rebinding concentration were compared, and errors between ?9.43% and 5.59% were found. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122:1847–1856, 2011  相似文献   

18.
Applicability of molecularly imprinted polymers (MIP) in conventional protein separation processes demands monolithic construction of columns with macroporous structure in addition to the high specificity and adsorption capacity. In this study, therefore, lysozyme (Lyz) imprinted monolithic cryogel columns were synthesized using electrostatic functional monomers (EFMs) to provide strong interactions between template and polymer, leading to specific recognition and capture of Lyz. SEM images and FTIR spectroscopy analysis confirmed the macroporous structure and presence of EFMs in the samples. Adsorption isotherms, heterogeneity, and breakthrough curves as well as selectivity of the molecularly imprinted cryogels (EFMs‐MIC) and non‐imprinted cryogels (EFMs‐NIC) were investigated. Results showed effective imprinting with a maximum adsorption capacity of 211 mg/g and a high imprinting factor (IF) of 4.2 at low Lyz concentrations. A high relative selectivity coefficient of 7.24 was obtained for Lyz over cytochrome c, a competing protein, indicating that the imprinted sites could well distinguish Lyz. Reusability of MICs was also examined, where insignificant changes were observed in the cryogel adsorption/desorption characteristics after four cycles. Therefore, it is suggested to use EFMs and cryogelation in the synthesis of imprinted monolithic cryogels column for application in conventional protein separation processes. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42880.  相似文献   

19.
Imprinted polymers are now being increasingly considered for active biomedical uses such as drug delivery. In this work, the use of molecularly imprinted polymers (MIPs) in designing new drug delivery devices was studied. Imprinted polymers were prepared from methacrylic acid (MAA) (functional monomer), ethylene glycol dimethacrylate (cross‐linker), and dipyridamole (DIP) (as a drug template) using precipitation polymerization method. The influence of the template/functional monomer proportion and pH on the achievement of MIPs with nanopore cavities with a high enough affinity for the drug was investigated. The small pores (average 3.9 nm) in the imprinted microspheres show excellent retention properties for the target analyte. The polymeric devices were further characterized by FT‐IR, thermogravimetric analysis, scanning electron microscopy, photon correlation spectroscopy, Brunauer‐Emmett‐Teller analysis, and binding experiments. The imprinted polymers showed a higher affinity for DIP and a slower release rate than the nonimprinted polymers. The controlled releases of DIP from the prepared imprinted polymers were investigated by an in vitro dissolution test by measuring the absorbance at 284 nm by means of a UV–Visible spectrophotometer. Loaded imprinted microsphers showed very slow release in various solutions such as phosphate buffer solution (pH 6.8), HCl (pH 1.0) and mixture of HCl and MeOH at 37.0 ± 0.5°C and were able to prolong DIP release for more than two days. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

20.
和厚朴酚分子印迹聚合物微球的制备及表征   总被引:1,自引:0,他引:1  
采用单步溶胀聚合法制备了和厚朴酚分子印迹聚合物微球(MIPMs)。Scatchard分析表明分子印迹聚合物微球在识别和厚朴酚分子的过程中存在两类结合位点,其高亲和位点的解离常数为KD1=0.13 mmol/L,最大表观结合量Qmax=45.21μmol/g。静态吸附试验证明MIPMs对模板分子具有较强的特异吸附能力,以厚朴酚为竞争底物,其分离因子达1.85。  相似文献   

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