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141.
A chemical derivatization technique in ToF-SIMS along with principal component analysis (PCA) were used to perform a quantitative study of the surface amine density of the plasma-polymerized ethylenediamine (PPEDA) thin film. We used the scores on principal component (PC) 1 from a PCA of ToF-SIMS data for the PPEDA films and their chemical-derivatized surfaces for comparison with the surface amine densities. These surface amine densities were independently determined by UV-visible spectroscopy. Our work found a good linear relationship between the surface amine densities and the scores on PC 1 from a PCA of the ToF-SIMS data for the chemical-derivatized PPEDA surfaces, but not for the PPEDA thin films themselves. In addition to quantification, our PCA results provided insights into the surface chemical composition of each surface. 相似文献
142.
Dually Electroactive Disulfide‐Confined Aryldiazonium Salt Used as a Linker Molecule for Preparing Immunosensor Platforms
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Md. Mohibul Islam Khan Mithrabinda K. Poduval Tae‐Hyun Kim Kyuwon Kim 《Electroanalysis》2015,27(8):1952-1959
A new electroactive disulfide‐confined aryl diazonium (DSAD) salt was synthesized and used as a linker for biomolecules immobilization to prepare two kinds of immunoassay platforms. DSAD was electrodeposited on ITO electrode surfaces by cyclic voltammetry. Disulfide group of DSAD attached on the surfaces were electrochemically oxidized into thiosulfinate or thiosulfonate groups. For the first work, a detection of rabbit antigen was performed on ITO microelectrodes array by spatially‐selective approach. In the second work, DSAD was deposited on electrochemically reduced graphene oxide‐modified ITO surfaces, which were used as a platform for electrochemical sandwich immunoassay for detecting mouse antigen. 相似文献
143.
Byung Hyun Kang Hye Sook Min You Jeong Lee Bomi Choi Eun Ji Kim Jonghoon Lee Jeong-Rae Kim Kwang-Hyun Cho Tae Jin Kim Kyeong Cheon Jung Seong Hoe Park 《Experimental & molecular medicine》2015,47(3):e154
Analysis of the T-cell receptor (TCR) repertoire of innate CD4+ T cells selected by major histocompatibility complex (MHC) class II-dependent thymocyte–thymocyte (T-T) interaction (T-T CD4+ T cells) is essential for predicting the characteristics of the antigens that bind to these T cells and for distinguishing T-T CD4+ T cells from other types of innate T cells. Using the TCRmini Tg mouse model, we show that the repertoire of TCRα chains in T-T CD4+ T cells was extremely diverse, in contrast to the repertoires previously described for other types of innate T cells. The TCRα chain sequences significantly overlapped between T-T CD4+ T cells and conventional CD4+ T cells in the thymus and spleen. However, the diversity of the TCRα repertoire of T-T CD4+ T cells seemed to be restricted compared with that of conventional CD4+ T cells. Interestingly, the frequency of the parental OT-II TCRα chains was significantly reduced in the process of T-T interaction. This diverse and shifted repertoire in T-T CD4+ T cells has biological relevance in terms of defense against diverse pathogens and a possible regulatory role during peripheral T-T interaction. 相似文献
144.
Gold Nanorod–Photosensitizer Complex Obtained by Layer‐by‐Layer Method for Photodynamic/Photothermal Therapy In Vitro
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Seung Beom Kim Tae Heon Lee Prof. Il Yoon Prof. Young Key Shim Prof. Woo Kyoung Lee 《化学:亚洲杂志》2015,10(3):563-567
Gold nanorod (GNR)–photosensitizer (PS) complex was prepared using anionic PS (sodium salt of purpurin‐18) and cationic poly(allylamine hydrochloride) by layer‐by‐layer method, and was characterized by transmission electron microscopy, UV‐vis spectroscopy, and zeta potential. The GNR–PS complex is a promising agent for synergistic (photothermal and photodynamic) therapy (PTT/PDT), in which PTT generates heat as well as operates the PS release which maximize the following PDT activity. The combined dual therapy, PTT followed by PDT, exhibits a significantly higher photocytotoxicity result based on synergistic effect of hyperthermia from PTT as well as singlet oxygen photogeneration from PDT. 相似文献
145.
Hari Jang Jin Woo Lee Qinghao Jin Soo‐Young Kim Dongho Lee Jin Tae Hong Youngsoo Kim Mi Kyeong Lee Bang Yeon Hwang 《Helvetica chimica acta》2015,98(10):1419-1425
Two new biflavones, (aR)‐3′‐methoxycupressuflavone ( 1 ) and (aR)‐3′,3′′′‐dimethoxycupressuflavone ( 2 ), and two new furanone glucosides, zabeliosides A and B ( 3 and 4 , resp.), along with two known biflavones, cupressuflavone ( 5 ) and amentoflavone ( 6 ), were isolated from the leaves of Zabelia tyaihyonii. The structures of the new compounds were elucidated by 1D‐ and 2D‐NMR, HR‐ESI‐MS, and circular dichroism. 相似文献
146.
Ki Dong Yang Woo Ri Ko Jun Ho Lee Prof. Sung Jae Kim Prof. Hyomin Lee Prof. Min Hyung Lee Prof. Ki Tae Nam 《Angewandte Chemie (International ed. in English)》2017,56(3):796-800
The electrocatalytic conversion of CO2 to value-added hydrocarbons is receiving significant attention as a promising way to close the broken carbon-cycle. While most metal catalysts produce C1 species, such as carbon monoxide and formate, the production of various hydrocarbons and alcohols comprising more than two carbons has been achieved using copper (Cu)-based catalysts only. Methods for producing specific C2 reduction outcomes with high selectivity, however, are not available thus far. Herein, the morphological effect of a Cu mesopore electrode on the selective production of C2 products, ethylene or ethane, is presented. Cu mesopore electrodes with precisely controlled pore widths and depths were prepared by using a thermal deposition process on anodized aluminum oxide. With this simple synthesis method, we demonstrated that C2 chemical selectivity can be tuned by systematically altering the morphology. Supported by computational simulations, we proved that nanomorphology can change the local pH and, additionally, retention time of key intermediates by confining the chemicals inside the pores. 相似文献
147.
Qinghao Jin Chul Lee Jin Woo Lee Jeong Yeon Choi Jin Tae Hong Youngsoo Kim Mi Kyeong Lee Bang Yeon Hwang 《Helvetica chimica acta》2014,97(8):1152-1157
A phytochemical investigation of the fruits of Melia azedarach led to the isolation of two new C‐seco‐nimbolinin‐type limonoids, 3α‐acetoxy‐1α,7α‐dihydroxy‐12α‐methoxynimbolinin ( 1 ) and 3α‐acetoxy‐1α,12α‐dihydroxy‐7α‐(2‐methylprop‐2‐enoyl)nimbolinin ( 2 ), together with eleven known compounds, 3 – 13 . Their structures were elucidated on the basis of extensive spectroscopic analysis, including 1H‐ and 13C‐NMR, HMQC, HMBC, NOESY, and HR‐FAB‐MS. 相似文献
148.
TiO2–SiO2 in PEG: A Highly Efficient Green Catalytic System for One‐Pot Synthesis of Benzo[a]xanthen‐11‐ones
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Mudumala Veeranarayana Reddy Se Mo Son Yeon Tae Jeong 《Journal of heterocyclic chemistry》2014,51(5):1246-1250
Polyethylene glycol was found to be an inexpensive non‐toxic and effective medium for the one‐pot synthesis of benzo[a]xanthen‐11‐ones in the presence of TiO2–SiO2 as the catalyst in good to excellent yield. The salient features of this protocol are the simplicity of the procedure, the ready accessibility of the catalyst, its cost effectiveness, and reusable catalyst in relatively short reaction times. 相似文献
149.
Mudumala Veeranarayana ReddySomeshwar D. Dindulkar Yeon Tae Jeong 《Tetrahedron letters》2011,52(37):4764-4767
α-Aminophosphonates were synthesized in a simple and efficient method from the three-component condensation reaction of 5-amino 2,2-difluoro-1,3-benzodioxole, aromatic aldehydes, and diethyl phosphite by silica-supported boron trifluoride (BF3·SiO2) in ionic liquid ([bmim][HCl]) under solvent-free conditions at room temperature in good to excellent yields and short reaction times. The catalyst can be recovered and reused for several times without any significant loss of activity. It was observed that a homogeneous reaction medium proved beneficial for the yield of the reaction. 相似文献
150.
Yong Kyun Sim Suhyun Jung Jung Yun LimJuhyun Kim Seong-Ho KimBong Keun Song Bum Tae KimHyuk Lee Seongsoon Park 《Tetrahedron letters》2011,52(9):1041-1043
A facile process was developed to manufacture biocatalyst-conjugated magnetic nanobeads, which afford no loss of the intrinsic activity and enantioselectivity of biocatalysts. Up to 90% of their activities remained after six-time recycling in aqueous media. 相似文献