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941.
Karl Gatterdam Eike F. Joest Dr. Marina S. Dietz Prof. Dr. Mike Heilemann Prof. Dr. Robert Tampé 《Angewandte Chemie (International ed. in English)》2018,57(20):5620-5625
Live‐cell labeling, super‐resolution microscopy, single‐molecule applications, protein localization, or chemically induced assembly are emerging approaches, which require specific and very small interaction pairs. The minimal disturbance of protein function is essential to derive unbiased insights into cellular processes. Herein, we define a new class of hexavalent N‐nitrilotriacetic acid (hexaNTA) chelators, displaying the highest affinity and stability of all NTA‐based small interaction pairs described so far. Coupled to bright organic fluorophores with fine‐tuned photophysical properties, the super‐chelator probes were delivered into human cells by chemically gated nanopores. These super‐chelators permit kinetic profiling, multiplexed labeling of His6‐ and His12‐tagged proteins as well as single‐molecule‐based super‐resolution imaging. 相似文献
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943.
Dr. Zhizeng Gao Dr. Andrew J. Thompson Prof. James C. Paulson Prof. Stephen G. Withers 《Angewandte Chemie (International ed. in English)》2018,57(41):13538-13541
Reagents to visualize and localize neuraminidase activity would be valuable probes to study the role of neuraminidases in normal cellular processes as well as during viral infections or cancer development. Herein, a new class of neuraminidase‐imaging probes that function as proximity ligation reagents by releasing a highly reactive fluorophore that tags nearby cellular material is described. It is further demonstrated that it is possible to create an influenza virus‐specific reagent, which can specifically detect influenza virus infections in mammalian cells. These reagents have potential use as specific histological probes independent of viral antigenicity and, therefore, offer some advantages over commonly used anti‐neuraminidase antibodies. 相似文献
944.
Back Cover: Single‐Nanoparticle Cell Barcoding by Tunable FRET from Lanthanides to Quantum Dots (Angew. Chem. Int. Ed. 41/2018)
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945.
Yuliang Jiang Sheng Zhang Bingxiang Wang Tao Qian Can Jin Shishan Wu Jian Shen 《Tetrahedron》2018,74(39):5733-5738
Hypochlorite (OCl?) plays important roles both in physiological and pathological processes, the detection of which is of great significance. Herein, a novel fluorescent probe based on the triphenylamine-type schiff base derivative (TPAD) was developed to detect OCl?. Probe TPAD exhibited specific fluorescence response toward ClO? with the fluorescence quenching rate up to 80%, and the detection limit was estimated to be 0.8?μM. The sensing mechanism study demonstrated that TPAD reacted with ClO?via an oxidation process, which was evidenced by MS and NMR characterization. Moreover, owing to the excellent sensing properties and negligible cytotoxicity, TPAD was successfully applied in the bioimaging of OCl? in living A549?cells. 相似文献
946.
Dr. Qingqing Miao Dr. David C. Yeo Dr. Christian Wiraja Dr. Jianjian Zhang Xiaoyu Ning Prof. Chenjie Xu Prof. Kanyi Pu 《Angewandte Chemie (International ed. in English)》2018,57(5):1256-1260
Early detection of skin diseases is imperative for their effective treatment. However, fluorescence molecular probes that allow this are rare. The first activatable near‐infrared (NIR) fluorescent molecular probe is reported for sensitive imaging of keloid cells, skin cells from abnormal scar fibrous lesions. As keloid cells have high expression levels of fibroblast activation protein‐alpha (FAPα), the probe (FNP1) is designed to have a caged NIR dye and a FAPα‐cleavable peptide substrate linked by a self‐immolative segment. FNP1 can quickly and specifically turn on its fluorescence at 710 nm by 45‐fold in the presence of FAPα, allowing it to effectively recognize keloid cells from normal skin cells. Integration of FNP1 with a simple microneedle‐assisted topical application enables sensitive detection of keloid cells in metabolically‐active human skin tissue with a theoretical limit of detection down to 20 000 cells. 相似文献
947.
Imaging of Colorectal Cancers Using Activatable Nanoprobes with Second Near‐Infrared Window Emission
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Ge Xu Qinglong Yan Xiaoguang Lv Prof. Ying Zhu Kai Xin Ben Shi Rongchen Wang Jian Chen Wei Gao Prof. Ping Shi Prof. Chunhai Fan Prof. Chunchang Zhao Prof. He Tian 《Angewandte Chemie (International ed. in English)》2018,57(14):3626-3630
Fluorescent probes in the second near‐infrared window (NIR‐II) allow high‐resolution bioimaging with deep‐tissue penetration. However, existing NIR‐II materials often have poor signal‐to‐background ratios because of the lack of target specificity. Herein, an activatable NIR‐II nanoprobe for visualizing colorectal cancers was devised. This designed probe displays H2S‐activated ratiometric fluorescence and light‐up NIR‐II emission at 900–1300 nm. By using this activatable and target specific probe for deep‐tissue imaging of H2S‐rich colon cancer cells, accurate identification of colorectal tumors in animal models were performed. It is anticipated that the development of activatable NIR‐II probes will find widespread applications in biological and clinical systems. 相似文献
948.
The photodissociation dynamics of isocyanic acid (HNCO) has been studied by the timesliced velocity map ion imaging technique at 193 nm. The NH(aΔ) products were measured via (2+1) resonance enhanced multiphoton ionization. Images have been accumulated for the NH(aΔ) rotational states in the ground and vibrational excited state (v=0 and 1). The center-of-mass translational energy distribution derived from the NH(aΔ) images implies that the CO vibrational distributions are inverted for most of the measured NH(v|j) internal states. The anisotropic product angular distribution observed indicates a rapid dissociation process for the N-C bond cleavage. A bimodal rotational state distribution of CO(v) has been observed, this result implies that isocyanic acid dissociates in the S1 state in two different pathways. 相似文献
949.