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181.
The role of molecularly imprinted polymers (MIPs) is changing from academic to applied researches. Challenging problems about MIP will be more highlighted in applicable uses and solving these problems is vital. The controlled/“living” radical polymerization (CLRP) techniques are applicable to solve the challenging problems in MIPs. The “living” nature of CLRP helps to improve the heterogeneity of binding sites in MIPs as a main challenge where precise control over sizes, compositions, and surface functionalities is achieved. Among different techniques of CLRP, reversible addition-fragmentation chain transfer (RAFT) technique presents distinguished benefits such as compatibility and tolerance to a wide range of functional monomers and mild reaction conditions rather than other CLRP techniques. In this review, in order to obtain more insights into the potential benefits of RAFT polymerization in fabrication of nano and micro MIP networks, recent research in advanced MIP materials for different templates with improved morphology, efficiency, and binding capacities with respect to traditional free radical polymerization (FRP) will be discussed. MIPs prepared via RAFT method have advantages of MIPs as high performance molecular recognition devices and CLRP as controllable polymerization mechanism, simultaneously. 相似文献
182.
Poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction agarose resins with 5‐aminobenzimidazole as a functional ligand
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Tao Liu Dong‐Qiang Lin Cun‐Xiang Wang Shan‐Jing Yao 《Journal of separation science》2016,39(16):3130-3136
Hydrophobic charge‐induction chromatography is a new technology for antibody purification. To improve antibody adsorption capacity of hydrophobic charge‐induction resins, new poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction resins with 5‐aminobenzimidazole as a functional ligand were prepared. Adsorption isotherms, kinetics, and dynamic binding behaviors of the poly(glycidyl methacrylate)‐grafted resins prepared were investigated using human immunoglobulin G as a model protein, and the effects of ligand density were discussed. At the moderate ligand density of 330 μmol/g, the saturated adsorption capacity and equilibrium constant reached the maximum of 140 mg/g and 25 mL/mg, respectively, which were both much higher than that of non‐grafted resin with same ligand. In addition, effective pore diffusivity and dynamic binding capacity of human immunoglobulin G onto the poly(glycidyl methacrylate)‐grafted resins also reached the maximum at the moderate ligand density of 330 μmol/g. Dynamic binding capacity at 10% breakthrough was as high as 76.3 mg/g when the linear velocity was 300 cm/h. The results indicated that the suitable polymer grafting combined with the control of ligand density would be a powerful tool to improve protein adsorption of resins, and new poly(glycidyl methacrylate)‐grafted hydrophobic charge‐induction resins have a promising potential for antibody purification applications. 相似文献
183.
Is Cd2 truly a van der Waals molecule? Analysis of rotational profiles recorded at the , transitions
Rotational profiles of the 228Cd2 isotopomer recorded in the (υ′, υ″) = (26, 0), (27, 0), (42, 0), (45, 0), (46, 0), (48, 0) vibrational bands of the transition were analysed. As a result, the , , , , and excited- as well as the ground-state rotational constants of the (114Cd)2 were determined. The analysis allowed determining the absolute values for the and excited- and ground-state bond lengths, respectively. The obtained result – the – distinctly shorter than that obtained with assumption of pure ground-state van der Waals bonding, supports a theoretical prediction of a covalent admixture to the bonding. Analysis of the partially-resolved rotational profile recorded in the (υ′, υ″) = (38, 0) band of the same isotopomer recorded at the transition allowed estimating the rotational constant in the B1u state. 相似文献
184.
A new fluorescent dye, N-allyl-4-morpholinyl-1,8-naphthalimide (AMN), was synthesized as a fluorescence indicator in the fabrication of a sensor for
determining water content in organic solvents. To prevent leakage of the fluorophore, AMN was photo-copolymerized with acrylamide,
(2-hydroxyethyl)methacrylate, and triethylene glycol dimethacrylate on a glass surface treated with a silanizing agent. The
sensing mechanism is based on the solvatochromic feature of the covalently immobilized AMN. The fluorescence intensity of
AMN decreased with increasing water contents when it was excited at 400 nm. In the range of ca. 0.00–4.40% (v/v), the fluorescence
intensity of AMN changed as a linear function of water content. The sensor exhibited satisfactory reproducibility, reversibility,
and a response time (t
99) of the order of 50 s. The detection limit was solvent-dependent, when acetonitrile was used as the solvent, and the detection
limit could be as low as 0.006% (v/v) of water. Additionally, the prepared sensor is pH-insensitive and possesses a relatively
long lifetime of at least one month. 相似文献
185.
Sun Y Yan F Yang W Zhao S Yang W Sun C 《Analytical and bioanalytical chemistry》2007,387(4):1565-1572
In this work we present a strategy for the covalent immobilization of periodate oxidized glucose oxidase () to aminated silica nanoparticles (ASNPs) modified on gold electrodes. Silica nanoparticles greatly enhanced the catalytic
ability of GOx toward the oxidation of glucose and improved the electron transfer between the GOx and the electrode surface.
ASNPs of varying size—that is 100, 80, 60, and 30 nm—were prepared, and they were used to fabricate biosensors. Electrochemical
impedance spectroscopy (EIS) of ferrocyanide followed the assembly process and verified the successful immobilization of on ASNPs modified on gold electrodes. From the analysis of catalytic signals of biosensors using different sizes of ASNPs
under the same conditions, the surface concentration of electrically wired enzyme (Γ
ET) was estimated and was found to increase with decreasing ASNPs size. Therefore, the sensitivity of biosensors using smaller
ASNPs was higher than that using larger particles. Specifically, we utilized the ASNPs with optimal size (30 nm) to fabricate
the glucose biosensor. The resulting electrodes showed a wide linear response to glucose at least to 6 mM and reached 95%
of the steady-state current in less than 4 s with a sensitivity of 5.02 μA mM−1 cm−2 and a detection limit of 0.01 mM. The biosensor also showed excellent stability and good reproducibility.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users. 相似文献
186.
Studies of interactions between silane coupling agents and cellulose fibers with liquid and solid-state NMR 总被引:1,自引:0,他引:1
Salon MC Gerbaud G Abdelmouleh M Bruzzese C Boufi S Belgacem MN 《Magnetic resonance in chemistry : MRC》2007,45(6):473-483
The hydrolysis of three alkoxy-silane coupling agents, gamma-methacryloxypropyl trimethoxy silane (MPS), gamma-aminopropyl triethoxy silane (APS), and gamma-diethylenetriaminopropyl trimethoxy silane (TAS), was carried out in ethanol/water solutions (80/20 w/w) at different pH values and followed by 1H, 13C and 29Si NMR spectroscopy. Acidic media were found to stabilize the hydrolyzed forms. As expected, the formation of silanol groups was followed by their self-condensation to generate oligomeric structures, yielding, ultimately, solid homopolycondensated structures, as analyzed by 29Si and 13C high-resolution solid-state NMR. Hydrolyzed MPS in acidic media was then successfully adsorbed onto a cellulose surface and the ensuing substrates submitted to thermal treatment at 110-120 degrees C under reduced pressure, in order to create covalent bonds between cellulose and the coupling agent. 相似文献
187.
188.
对聚合物表面进行接枝聚合是一种有效的材料改性方法。近年来,S.Tazuke,Y.Ogiwara,高志民等人做了一些用紫外光引发接枝方面的工作,获得了较满意的结果。为提高聚丙烯(简称为PP)膜的光稳定性,我们研究了将一种受阻胺类光稳定剂,甲基丙烯酸2,2,6,6-四甲基哌啶醇酯(简称为MTMP)光接枝到PP膜表面的聚合过程。 相似文献
189.
190.