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141.
Artificial antibodies in the form of gel granules were prepared by the molecular imprinting technique from the monomers acrylamide and N,N'-methylene-bis-acrylamide. Gel granules, freed from the selectively adsorbed protein (the antigen), are neutral and, accordingly, do not migrate in an electrical field. However, upon selective interaction with the antigen at a pH different from its pI, the granules become charged. The selectivity of the gel antibodies was studied by free zone electrophoresis in a tube with inside diameter larger than the size of the granules. Such electrophoretic analyses showed that gel antibodies against iron-free transferrin had a high selectivity for this protein, although some crossreaction took place with iron-saturated transferrin, indicating that these artificial antibodies can easily distinguish the minute differences in the 3-D structure of the transferrins. Analogously, gel antibodies against iron-saturated transferrin were highly selective for this protein with some crossreaction with iron-free transferrin. The mobilities of iron-free and iron-saturated transferrin are very similar, and, therefore, capillary free zone electrophoresis cannot distinguish between these structurally related proteins. However, significant differences in the mobilities of the selective gel granules can be observed depending on their interaction with iron-free or iron-saturated transferrin, i.e., the artificial gel antibodies may become powerful analytical tools. 相似文献
142.
Ji-Yeon Park Ah-Reum Han Yun-Seo Kil Unwoo Kang Se-Hee Kim 《Natural product research》2016,30(13):1504-1510
A new secoiridoid glycoside, 7β-O-dimethyl butanedioate morroniside (1) was isolated from the fruits of Cornus officinalis (Cornaceae) along with the known compound, caffeoyltartaric acid dimethyl ester (2) which was isolated from the family Cornaceae for the first time. Their structures were elucidated by physical and spectroscopic data analysis, including 1D and 2D NMR, ESI-MS and CD experiments. 相似文献
143.
Yoon Yeol Yoon Soo Young Cho Kil Yong Lee Kyung Seok Ko Kyoochul Ha 《Journal of Radioanalytical and Nuclear Chemistry》2013,296(1):397-402
234U, 238U, 226Ra, and 228Ra were analyzed in 14 Korean hot spring waters. Uranium was extracted with mixture of extractive scintillation cocktail containing HDEHP and 234U, 238U were analyzed with LSC. Radium isotopes were separated using Ba coprecipitation method and counted with LSC and 228Ra was also analyzed its daughter 228Ac with HPGe γ-detector. Among them 226Ra was ranged <0.01–0.155 Bq/L and 228Ra is below detection limit <0.1 Bq/L. And also, uranium content was ranged <0.01–49.7 μg/L and 234U/238U ratio was ranged 0.69–1.17. 相似文献
144.
Yeasmin S Kim CH Park HJ Sheikh MI Lee JY Kim JW Back KK Kim SH 《Applied biochemistry and biotechnology》2011,164(3):294-304
Cellulase-free xylanase has potential for its application in the selective removal of hemicellulose from kraft pulp to give
good strength to paper. In this study, a gene (xyn) encoding cellulase activity–free xylanase enzyme (Xyn) was isolated from Paenibacillus polymyxa PPL-3. The xyn gene encoded a protein of 221 amino acids, and the purified Xyn was about 22.5 kDa measured by sodium dodecyl sulfate–polyacrylamide
gel electrophoresis. Moreover, the cellulase activity–free xylanase enzyme (Xyn) was displayed on the cell surface of Saccharomyces cerevisiae EBY100 using Aga2p as an anchor protein. Cell surface display of xylanase enzyme (Xyn) on S. cerevisiae EBY100 was confirmed by immunofluorescence microscopy. Optimum cell surface display of xylanase enzyme (Xyn) was observed
at pH 7 and 40 °C. Therefore, cell surface–displayed xylanase enzyme (Xyn) can be used in the paper industry. 相似文献
145.
Moon BS Kil HS Park JH Kim JS Park J Chi DY Lee BC Kim SE 《Organic & biomolecular chemistry》2011,9(24):8346-8355
Aromatic radiofluorination of the diaryliodonium tosylate precursor with [(18)F]fluoride ions has been applied successfully to access [(18)F]flumazenil in high radiochemical yields of 67.2 ± 2.7% (decay corrected). The stability and reactivity of the diaryliodonium tosylate precursor plays a key role in increasing the production of (18)F-labelled molecules under the fluorine-18 labelling condition. Various conditions were explored for the preparation of [(18)F]flumazenil from different diaryliodonium tosylate precursors. Optimum incorporation of [(18)F]fluoride ions in the 4-methylphenyl-mazenil iodonium tosylate precursor (5f) was achieved at 150 °C for 5 min by utilizing 4 mg of the precursor, K(2.2.2)/K(2)CO(3) complex, and the radical scavenger in N,N-dimethylformamide. This approach was extended to a viable method for use in automated synthesis with a radiochemical yield of 63.5 ± 3.2% (decay corrected, n = 26) within 60.0 ± 1.1 min. [(18)F]Flumazenil was isolated by preparative HPLC after the reaction was conducted under improved conditions and exhibited sufficient specific activity of 370-450 GBq μmol(-1), with a radiochemical purity of >99%, which will be suitable for human PET studies. 相似文献
146.
A hydrogen-bond-assisted model is proposed for ring-opening metathesis polymerization (ROMP) of a secondary amide of 1-cyclobutene, resulting in the fastest reaction rate in a nonpolar solvent, toluene. This new model was supported by the investigation on how the solvent effect affected the NMR spectra, ROMP kinetic studies, and the copolymerization of monomers 1 and 2. 相似文献
147.
148.
Kim KS Noh SB Katsuda T Ito S Osuka A Kim D 《Chemical communications (Cambridge, England)》2007,(24):2479-2481
Intramolecular charge transfer in 5,15-bis(azulenylethynyl) substituted zinc(ii) porphyrin leads to a significant enhancement of two-photon absorption at near-IR region, which has been investigated by femtosecond Z-scan method. 相似文献
149.
150.
Dinuclear [(TPyA)FeII(DBQ2-)FeII(TPyA)](BF4)2 possesses extensive pi-pi interactions between the FeII dimers that give rise to a two-dimensional supramolecular sheet structure. The magnetic susceptibility shows a room-temperature spin-crossover behavior; however, thermal hysteresis is not observed. 相似文献