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51.
Patrick H. Maag Dr. Florian Feist Dr. Vinh X. Truong Dr. Hendrik Frisch Prof. Peter W. Roesky Prof. Christopher Barner-Kowollik 《Angewandte Chemie (International ed. in English)》2023,62(37):e202309259
We introduce a class of single-chain nanoparticles (SCNPs) that respond to visible light (λmax=415 nm) with complete unfolding from their compact structure into linear chain analogues. The initial folding is achieved by a simple esterification reaction of the polymer backbone constituted of acrylic acid and polyethylene glycol carrying monomer units, introducing bimane moieties, which allow for the photochemical unfolding, reversing the ester-bond formation. The compaction and the light driven unfolding proceed cleanly and are readily followed by size exclusion chromatography (SEC) and diffusion ordered NMR spectroscopy (DOSY), monitoring the change in the hydrodynamic radius (RH). Importantly, the folding reaction and the light-induced unfolding are reversible, supported by the high conversion of the photo cleavage. As the unfolding reaction occurs in aqueous systems, the system holds promise for controlling the unfolding of SCNPs in biological environments. 相似文献
52.
Alessandro Bismuto Patrick Finkelstein Patrick Müller Bill Morandi 《Helvetica chimica acta》2021,104(12):e2100177
In the last twenty years, nickel has successfully imprinted its role in the field of homogeneous catalysis as a valid and complementary alternative to palladium and platinum catalysts. However, compared to those, there are often many different available pathways in nickel catalysis due to the facile access of intermediate oxidation states. Among them, Ni(I) has been increasingly proposed as a key oxidation state in multiple transformations. This oxidation state had already been suggested a long time ago but has only recently undergone a renaissance with extensive ligand design which has led to over 100 isolated Ni(I) complexes. In addition, the analysis of many catalytic cycles has revealed that the Ni(I) species can not only occur as a decomposition product perturbing a Ni(0)–Ni(II) pathway but can also play a key role in alternative Ni(I)–Ni(III) cycles. This behavior is highly dependent on the class of transformation and ligand employed in catalysis. Herein, we concisely describe the journey of this oxidation state, combining the information gathered from inorganic synthesis and mechanistic investigations, from its synthesis to its postulated role in different catalytic cycles. 相似文献
53.
Dhont Guillaume Cassam-Chenaï Patrick Patras Frédéric 《Journal of mathematical chemistry》2021,59(10):2294-2326
Journal of Mathematical Chemistry - The construction of integrity bases for invariant and covariant polynomials built from a set of three dimensional vectors under the $${{\mathrm {SO(3)}}}$$ and... 相似文献
54.
55.
Patrick M. TomHon Dr. Suyong Han Dr. Sören Lehmkuhl Prof. Stephan Appelt Prof. Eduard Y. Chekmenev Prof. Milad Abolhasani Prof. Thomas Theis 《Chemphyschem》2021,22(24):2526-2534
We introduce a Spin Transfer Automated Reactor (STAR) that produces continuous parahydrogen induced polarization (PHIP), which is stable for hours to days. We use the PHIP variant called signal amplification by reversible exchange (SABRE), which is particularly well suited to produce continuous hyperpolarization. The STAR is operated in conjunction with benchtop (1.1 T) and high field (9.4 T) NMR magnets, highlighting the versatility of this system to operate with any NMR or MRI system. The STAR uses semipermeable membranes to efficiently deliver parahydrogen into solutions at nano to milli Tesla fields, which enables 1H, 13C, and 15N hyperpolarization on a large range of substrates including drugs and metabolites. The unique features of the STAR are leveraged for important applications, including continuous hyperpolarization of metabolites, desirable for examining steady-state metabolism in vivo, as well as for continuous RASER signals suitable for the investigation of new physics. 相似文献
56.
Dr. Ileana-Alexandra Pavel Dr. Gerardo Salinas Dr. Maciej Mierzwa Dr. Serena Arnaboldi Patrick Garrigue Prof. Alexander Kuhn 《Chemphyschem》2021,22(13):1321-1325
Numerous artificial micro- and nanomotors, as well as various swimmers have been inspired by living organisms that are able to move in a coordinated manner. Their cooperation has also gained a lot of attention because the resulting clusters are able to adapt to changes in their environment and to perform complex tasks. However, mimicking such a collective behavior remains a challenge. In the present work, magnesium microparticles are used as chemotactic swimmers with pronounced collective features, allowing the gradual formation of macroscopic agglomerates. The formed clusters act like a single swimmer able to follow pH gradients. This dynamic behavior can be used to spot localized corrosion events in a straightforward way. The autonomous docking of the swimmers to the corrosion site leads to the formation of a local protection layer, thus increasing corrosion resistance and triggering partial self-healing. 相似文献
57.
Dr. Uttam Chakraborty Patrick Bügel Lorena Fritsch Dr. Florian Weigend Prof. Dr. Matthias Bauer Prof. Dr. Axel Jacobi von Wangelin 《ChemistryOpen》2021,10(2):265-271
The controlled assembly of well-defined planar nanoclusters from molecular precursors is synthetically challenging and often plagued by the predominant formation of 3D-structures and nanoparticles. Herein, we report planar iron hydride nanoclusters from reactions of main group element hydrides with iron(II) bis(hexamethyldisilazide). The structures and properties of isolated Fe4, Fe6, and Fe7 nanoplatelets and calculated intermediates enable an unprecedented insight into the underlying building principle and growth mechanism of iron clusters, metal monolayers, and nanoparticles. 相似文献
58.
The generation of highly organized amyloid fibrils is associated with a wide range of conformational pathologies, including primarily neurodegenerative diseases. Such disorders are characterized by misfolded proteins that lose their normal physiological roles and acquire toxicity. Recent findings suggest that proteostasis network impairment may be one of the causes leading to the accumulation and spread of amyloids. These observations are certainly contributing to a new focus in anti‐amyloid drug design, whose efforts are so far being centered on single‐target approaches aimed at inhibiting amyloid aggregation. Chaperones, known to maintain proteostasis, hence represent interesting targets for the development of novel therapeutics owing to their potential protective role against protein misfolding diseases. In this minireview, research on nanoparticles that can either emulate or help molecular chaperones in recognizing and/or correcting protein misfolding is discussed. The nascent concept of “nanochaperone” may indeed set future directions towards the development of cost‐effective, disease‐modifying drugs to treat several currently fatal disorders. 相似文献
59.
Santos Jovy Ann Simon Paulo Bernot Anthony R. Babasi Christopher Ward Patrick A. Hwang Son-Jong Zidan Ragaiy Teprovich Joseph A. 《Journal of Solid State Electrochemistry》2021,25(4):1441-1452
Journal of Solid State Electrochemistry - In this work, we evaluate the electrochemical properties of MBH4-C60 (M = Li+, Na+) nanocomposites for potential use as a solid-state electrolyte in... 相似文献
60.
Solomon Tesfaye Hannah Braun Kaleab Asres Ephrem Engidawork Anteneh Belete Ilias Muhammad Christian Schulze Nadin Schultze Sebastian Guenther Patrick J. Bednarski 《Molecules (Basel, Switzerland)》2021,26(12)
Medicinal plants have been traditionally used to treat cancer in Ethiopia. However, very few studies have reported the in vitro anticancer activities of medicinal plants that are collected from different agro-ecological zones of Ethiopia. Hence, the main aim of this study was to screen the cytotoxic activities of 80% methanol extracts of 22 plants against human peripheral blood mononuclear cells (PBMCs), as well as human breast (MCF-7), lung (A427), bladder (RT-4), and cervical (SiSo) cancer cell lines. Active extracts were further screened against human large cell lung carcinoma (LCLC-103H), pancreatic cancer (DAN-G), ovarian cancer (A2780), and squamous cell carcinoma of the esophagus (KYSE-70) by using the crystal violet cell proliferation assay, while the vitality of the acute myeloid leukemia (HL-60) and histiocytic lymphoma (U-937) cell lines was monitored in the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) microtiter assay. Euphorbia schimperiana, Acokanthera schimperi, Kniphofia foliosa, and Kalanchoe petitiana exhibited potent antiproliferative activity against A427, RT-4, MCF-7, and SiSo cell lines, with IC50 values ranging from 1.85 ± 0.44 to 17.8 ± 2.31 µg/mL. Furthermore, these four extracts also showed potent antiproliferative activities against LCLC-103H, DAN-G, A2780, KYSE-70, HL-60, and U-937 cell lines, with IC50 values ranging from 0.086 to 27.06 ± 10.8 µg/mL. Hence, further studies focusing on bio-assay-guided isolation and structural elucidation of active cytotoxic compounds from these plants are warranted. 相似文献