排序方式: 共有57条查询结果,搜索用时 15 毫秒
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Po‐Jung Jimmy Huang Donatien de Rochambeau Hanadi F. Sleiman Juewen Liu 《Angewandte Chemie (International ed. in English)》2020,59(9):3573-3577
Highly selective recognition of metal ions by rational ligand design is challenging, and simple metal binding by biological ligands is often obscured by nonspecific interactions. In this work, binding‐triggered catalysis is used and metal selectivity is greatly increased by increasing the number of metal ions involved, as exemplified in a series of in vitro selected RNA‐cleaving DNAzymes. The cleavage junction is modified with a glycyl–histidine‐functionalized tertiary amine moiety to provide multiple potential metal coordination sites. DNAzymes that bind 1, 2, and 3 Zn2+ ions, increased their selectivity for Zn2+ over Co2+ ions from approximately 20‐, 1000‐, to 5000‐fold, respectively. This study offers important insights into metal recognition by combining rational ligand design and combinatorial selection, and it provides a set of new DNAzymes with excellent selectivity for Zn2+ ions. 相似文献
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Alexander L. Prinzen Daniel Saliba Christopher Hennecker Tuan Trinh Prof. Anthony Mittermaier Prof. Hanadi F. Sleiman 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):13000-13008
Triggering the release of small molecules in response to unique biomarkers is important for applications in drug delivery and biodetection. Due to low quantities of biomarker, amplifying release is necessary to gain appreciable responses. Nucleic acids have been used for both their biomarker-recognition properties and as stimuli, notably in amplified small-molecule release by nucleic-acid-templated catalysis (NATC). The multiple components and reversibility of NATC, however, make it difficult to apply in vivo. Herein, we report the use of the hybridization chain reaction (HCR) for the amplified, conditional release of small molecules from standalone nanodevices. We couple HCR with a DNA-templated reaction resulting in the amplified, immolative release of small molecules. We integrate the HCR components into single nanodevices as DNA tracks and spherical nucleic acids, spatially isolating reactive groups until triggering. This could be applied to biosensing, imaging, and drug delivery. 相似文献
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Katherine J. Castor Zhaomin Liu Dr. Johans Fakhoury Dr. Mark A. Hancock Prof. Anthony Mittermaier Prof. Nicolas Moitessier Prof. Hanadi F. Sleiman 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(52):17836-17845
A series of three platinum(II) phenanthroimidazoles each containing a protonable side‐chain appended from the phenyl moiety through copper(I)‐catalyzed azide–alkyne cycloaddition (CuAAC) were evaluated for their capacities to bind to human telomere, c‐Myc, and c‐Kit derived G‐quadruplexes. The side‐chain has been optimized to enable a multivalent binding mode to G‐quadruplex motifs, which would potentially result in selective targeting. Molecular modeling, high‐throughput fluorescence intercalator displacement (HT‐FID) assays, and surface plasmon resonance (SPR) studies demonstrate that complex 2 exhibits significantly slower dissociation rates compared to platinum phenanthroimidazoles without side‐chains and other reported G‐quadruplex binders. Complex 2 showed little cytotoxicity in HeLa and A172 cancer cell lines, consistent with the fact that it does not follow a telomere‐targeting pathway. Preliminary mRNA analysis shows that 2 specifically interacts with the ckit promoter region. Overall, this study validates 2 as a useful molecular probe for c‐Kit related cancer pathways. 相似文献
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Daniel Saliba Tuan Trinh Christophe Lachance-Brais Alexander L. Prinzen Felix J. Rizzuto Donatien de Rochambeau Hanadi F. Sleiman 《Chemical science》2021,13(1):74
DNA tweezers have emerged as powerful devices for a wide range of biochemical and sensing applications; however, most DNA tweezers consist of single units activated by DNA recognition, limiting their range of motion and ability to respond to complex stimuli. Herein, we present an extended, tripodal DNA nanotweezer with a small molecule junction. Simultaneous, asymmetric elongation of our molecular core is achieved using polymerase chain reaction (PCR) to produce length- and sequence-specific DNA arms with repeating DNA regions. When rigidified, our DNA tweezer can be addressed with streptavidin-binding ligands. Full control over the number, separation, and location of these ligands enables site-specific streptavidin recognition; all three arms of the DNA nanotweezer wrap around multiple streptavidin units simultaneously. Our approach combines the simplicity of DNA tile arrays with the size regime normally provided by DNA origami, offering an integrated platform for the use of branched DNA scaffolds as structural building blocks, protein sensors, and dynamic, stimuli-responsive materials.An extended, multivalent DNA nanotweezer that undergoes large-scale molecular motion upon protein recognition is presented. Our method based on “printing-elongation-folding” combines the DNA-minimal aspect of DNA tile-based assembly, with complexity of DNA origami. 相似文献
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Dr. Po-Jung Jimmy Huang Dr. Donatien de Rochambeau Prof. Hanadi F. Sleiman Prof. Juewen Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(9):3601-3605
Highly selective recognition of metal ions by rational ligand design is challenging, and simple metal binding by biological ligands is often obscured by nonspecific interactions. In this work, binding-triggered catalysis is used and metal selectivity is greatly increased by increasing the number of metal ions involved, as exemplified in a series of in vitro selected RNA-cleaving DNAzymes. The cleavage junction is modified with a glycyl–histidine-functionalized tertiary amine moiety to provide multiple potential metal coordination sites. DNAzymes that bind 1, 2, and 3 Zn2+ ions, increased their selectivity for Zn2+ over Co2+ ions from approximately 20-, 1000-, to 5000-fold, respectively. This study offers important insights into metal recognition by combining rational ligand design and combinatorial selection, and it provides a set of new DNAzymes with excellent selectivity for Zn2+ ions. 相似文献
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Nikky Kortbeek Aleida Braaksma Ferry HF Smeenk Piet JM Bakker Richard J Boucherie 《The Journal of the Operational Research Society》2015,66(7):1061-1076
The design and operations of inpatient care facilities are typically largely historically shaped. A better match with the changing environment is often possible, and even inevitable due to the pressure on hospital budgets. Effectively organizing inpatient care requires simultaneous consideration of several interrelated planning issues. Also, coordination with upstream departments like the operating theatre and the emergency department is much-needed. We present a generic analytical approach to predict bed census on nursing wards by hour, as a function of the Master Surgical Schedule and arrival patterns of emergency patients. Along these predictions, insight is gained on the impact of strategic (ie, case mix, care unit size, care unit partitioning), tactical (ie, allocation of operating room time, misplacement rules), and operational decisions (ie, time of admission/discharge). The method is used in the Academic Medical Center Amsterdam as a decision-support tool in a complete redesign of the inpatient care operations. 相似文献