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71.
We synthesized a novel 1,3,5-substituted triethylbenzene derivative with a benzimidazole moiety as a binding and signalling subunit. The triethylbenzene platform was judiciously incorporated into the receptor design such that all the fluorophores are in close proximity to each other in order to facilitate stacking. The advantage of this approach lies in the fact that the receptor will offer a dual channel emission for the multiple ratiometric determination of metal ions. The sensor was tested in a CH3CN/H2O (7:3, v/v, pH 7.1) HEPES buffered solution and successfully developed for the ratiometric and simultaneous estimation of Fe3+ and Cu2+ ions in aqueous samples. 相似文献
72.
We synthesized a novel benzimidazole-based, anthracene-coupled fluorescent receptor capable of recognizing and estimating the concentrations of Fe3+ in semi-aqueous solution by ratiometric estimation. Our sensor can be made highly selective for Fe3+ over other metal ions by changing the solvent composition. 相似文献
73.
Yoo NY Youn YS Oh NM Oh KT Lee DK Cha KH Oh YT Lee ES 《Colloids and surfaces. B, Biointerfaces》2011,88(1):419-424
The purpose of this study was to fabricate porous poly(lactide-co-glycolide) (PLGA) microparticles for efficient pulmonary deposition and increased therapeutic duration of the antioxidant anthocyanin (ATH). These microparticles were prepared by a water-in-oil-in-water (W(1)/O/W(2)) multi-emulsion method with vaporizing ammonium bicarbonate (AB) as a porogen and starch as a viscous additive. High porosity achieved by the decomposition reaction of AB to the base of ammonia, carbon dioxide, and water vapor at 50°C enabled efficient deposition of ATH throughout the entire lung in BALB/c mice. In addition, the porous microparticles incorporating starch showed sustained ATH release characteristics (up to 5 days) and protracted antioxidant activity (up to 5 days) for 2,2-diphenyl-1-pikryl-hydrazyl (DPPH) radicals, which was comparable to that of the porous microparticles without starch which completely released ATH in 2h. Furthermore, these porous microparticles incorporating starch led to longer ATH residence (up to 20 days) in in vivo lung epithelium. We believe that this system has great pharmaceutical potential as a long-acting antioxidant for continuously relieving oxidative stress in pulmonary diseases like chronic obstructive pulmonary disease (COPD). 相似文献
74.
Spintronic devices are very important for futuristic information technology. Suitable materials for such devices should have half-metallic properties so that only one spin passes through the device. In particular, organic half metals have the advantage that they may be used for flexible devices and have a long spin-coherence length. We predict that the one-dimensional infinite chromium porphyrin array, which we call Cr-PA(∞), shows half-metallic behavior when the spins on the chromium atoms are in a parallel alignment. Since the chromium atoms are separated by a large distance (>8 ?), the coupling between spins is small and thus their directions can be readily controlled by an external magnetic field. In the ferromagnetic state, the band gap for major spin electrons is 0.30 eV, while there is no band gap for the minor spin electrons, thus reflecting the half-metallic property. This unique property originates from the high spin state of Cr which results in the spin asymmetry of the conduction band in Cr-PA(∞). Electron transport of Cr-PA(1,2,3) is calculated with the nonequilibrium Green function technique in the presence of Au electrodes. It turned out that the spin-filtering ability appears from the dimeric Cr-PA(2). Thus, a new organometallic framework for designing a spin filter is proposed. Though many others have designed novel spintronic devices, none of them are realized due to the lack of a practical fabrication method at present. However, the porphyrin-based spintronic device provides a synthesizable framework. 相似文献
75.
Lee SY Lee S Kho IH Lee JH Kim JH Chang JH 《Chemical communications (Cambridge, England)》2011,47(36):9989-9991
An enzyme-magnetic nanoparticle conjugate is prepared via conjugation of Ni(2+) ions onto the surface of magnetic nanoparticles to interact with a six histidine-tagged enzyme. The catalytic properties and enzyme rigidification of the conjugates are more stable at high concentrations of aromatic hydrocarbons. 相似文献
76.
Lee BR Oh KT Oh YT Baik HJ Park SY Youn YS Lee ES 《Chemical communications (Cambridge, England)》2011,47(13):3852-3854
We report charge-switching ionic nanocomplexes comprised of glycol chitosan grafted with 2,3-dimethylmaleic acid (DMA) (denoted as 'GCS-g-DMA' hereafter) and a proapoptotic peptide. This system allowed for improved peptide delivery to tumor sites via a mechanism of selective peptide release when the pH was dropped from 7.4 to 6.8. 相似文献
77.
Stable aluminium fluoride chelates with triazacyclononane derivatives proved by X-ray crystallography and 18F-labeling study 总被引:1,自引:0,他引:1
Shetty D Choi SY Jeong JM Lee JY Hoigebazar L Lee YS Lee DS Chung JK Lee MC Chung YK 《Chemical communications (Cambridge, England)》2011,47(34):9732-9734
A single crystal structure of an aluminium-fluoride complex of a model compound (NODA-benzyl) was studied to understand the co-ordination chemistry. Series of ligands with an extra carboxylic acid linker for biomolecule conjugation were studied for improved (18)F-labeling applications. 相似文献
78.
Kim YS Bae SY Kim KH Lee TW Hur JA Hoang MH Cho MJ Kim SJ Kim Y Kim M Lee K Lee SJ Choi DH 《Chemical communications (Cambridge, England)》2011,47(31):8907-8909
A new pyrene-cored π-conjugated molecule has been synthesized through Sonogashira coupling reaction. The single-crystalline microribbon-based FET exhibited the highest mobility of 0.7 cm(2) V(-1) s(-1) (I(on)/I(off) > 10(6)). Single-crystalline microribbons were employed to operate in an organic phototransistor (OPT) under very low light intensity (I = 5.6 μW cm(-2)). 相似文献
79.
80.
Hae-Jung Chae Geum-Jin Kim Barsha Deshar Hyun-Jin Kim Min-Ji Shin Hyukbean Kwon Ui-Joung Youn Joo-Won Nam Sung-Hak Kim Hyukjae Choi Sung-Suk Suh 《Molecules (Basel, Switzerland)》2021,26(13)
Colorectal cancer is one of the life-threatening ailments causing high mortality and morbidity worldwide. Despite the innovation in medical genetics, the prognosis for metastatic colorectal cancer in patients remains unsatisfactory. Recently, lichens have attracted the attention of researchers in the search for targets to fight against cancer. Lichens are considered mines of thousands of metabolites. Researchers have reported that lichen-derived metabolites demonstrated biological effects, such as anticancer, antiviral, anti-inflammatory, antibacterial, analgesic, antipyretic, antiproliferative, and cytotoxic, on various cell lines. However, the exploration of the biological activities of lichens’ metabolites is limited. Thus, the main objective of our study was to evaluate the anticancer effect of secondary metabolites isolated from lichen (Usnea barbata 2017-KL-10) on the human colorectal cancer cell line HCT116. In this study, 2OCAA exhibited concentration-dependent anticancer activities by suppressing antiapoptotic genes, such as MCL-1, and inducing apoptotic genes, such as BAX, TP53, and CDKN1A(p21). Moreover, 2OCAA inhibited the migration and invasion of colorectal cancer cells in a concentration-dependent manner. Taken together, these data suggest that 2OCAA is a better therapeutic candidate for colorectal cancer. 相似文献