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91.
Jolanta Pyteraf Witold Jamrz Mateusz Kurek Joanna Szafraniec-Szczsny Daniel Kramarczyk Karolina Jurkiewicz Justyna Knapik-Kowalczuk Jacek Tarasiuk Sebastian Wroski Marian Paluch Renata Jachowicz 《Molecules (Basel, Switzerland)》2021,26(11)
The flexibility of dose and dosage forms makes 3D printing a very interesting tool for personalized medicine, with fused deposition modeling being the most promising and intensively developed method. In our research, we analyzed how various types of disintegrants and drug loading in poly(vinyl alcohol)-based filaments affect their mechanical properties and printability. We also assessed the effect of drug dosage and tablet spatial structure on the dissolution profiles. Given that the development of a method that allows the production of dosage forms with different properties from a single drug-loaded filament is desirable, we developed a method of printing ketoprofen tablets with different dose and dissolution profiles from a single feedstock filament. We optimized the filament preparation by hot-melt extrusion and characterized them. Then, we printed single, bi-, and tri-layer tablets varying with dose, infill density, internal structure, and composition. We analyzed the reproducibility of a spatial structure, phase, and degree of molecular order of ketoprofen in the tablets, and the dissolution profiles. We have printed tablets with immediate- and sustained-release characteristics using one drug-loaded filament, which demonstrates that a single filament can serve as a versatile source for the manufacturing of tablets exhibiting various release characteristics. 相似文献
92.
利用可再生清洁能源将CO2转化为CO和其他小分子是合成含碳燃料的可观方法之一。间歇性可再生能源存储的重要策略之一是将二氧化碳进行电化学还原。选择具有高活性和稳定性的电催化剂对于电化学还原CO2至关重要。在这项研究中,我们使用简单的电沉积方法合成了具有纳米晶枝状结构的CuAu合金电极。各项表征显示原子比约为1:1的CuAu纳米枝晶对CO2的电化学还原具有出色的催化活性。合成的主要产物是H2和CO,这是合成气体是合成天然气,氨和甲醇合成的中间体。电化学阻抗谱(EIS)测量表明,相对于Cu和Au电沉积催化剂,CuAu纳米晶枝状催化剂具有相对低的电荷转移阻力。CuAu纳米枝晶催化剂是一种具有潜在的转化CO2为合成气体的高活性电催化剂。 相似文献
93.
Marina Huber-Gedert Dr. Michał Nowakowski Dr. Ahmet Kertmen Dr. Lukas Burkhardt Dr. Natalia Lindner Dr. Roland Schoch Dr. Regine Herbst-Irmer Dr. Adam Neuba Lennart Schmitz Tae-Kyu Choi Dr. Jacek Kubicki Prof. Dr. Wojciech Gawelda Prof. Dr. Matthias Bauer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(38):9905-9918
A new base metal iron-cobalt dyad has been obtained by connection between a heteroleptic tetra-NHC iron(II) photosensitizer combining a 2,6-bis[3-(2,6-diisopropylphenyl)imidazol-2-ylidene]pyridine with 2,6-bis(3-methyl-imidazol-2-ylidene)-4,4′-bipyridine ligand, and a cobaloxime catalyst. This novel iron(II)-cobalt(III) assembly has been extensively characterized by ground- and excited-state methods like X-ray crystallography, X-ray absorption spectroscopy, (spectro-)electrochemistry, and steady-state and time-resolved optical absorption spectroscopy, with a particular focus on the stability of the molecular assembly in solution and determination of the excited-state landscape. NMR and UV/Vis spectroscopy reveal dissociation of the dyad in acetonitrile at concentrations below 1 mM and high photostability. Transient absorption spectroscopy after excitation into the metal-to-ligand charge transfer absorption band suggests a relaxation cascade originating from hot singlet and triplet MLCT states, leading to the population of the 3MLCT state that exhibits the longest lifetime. Finally, decay into the ground state involves a 3MC state. Attachment of cobaloxime to the iron photosensitizer increases the 3MLCT lifetime at the iron centre. Together with the directing effect of the linker, this potentially makes the dyad more active in photocatalytic proton reduction experiments than the analogous two-component system, consisting of the iron photosensitizer and Co(dmgH)2(py)Cl. This work thus sheds new light on the functionality of base metal dyads, which are important for more efficient and sustainable future proton reduction systems. 相似文献
94.
Denis Mashkovtsev Wataru Mizukami Jacek Korchowiec Anna Stachowicz-Kuśnierz Yuriko Aoki 《Journal of computational chemistry》2020,41(25):2203-2212
The elongation method with intermediate mechanical and electrostatic embedding (ELG-IMEE) is proposed. The electrostatic embedding uses atomic charges generated by a charge sensitivity analysis (CSA) method and parameterized for three different population analyses, namely, the Merz–Singh–Kollman scheme, the charge model 5, and the atomic polar tensor. The obtained CSA models were tested on two model systems. Test calculations show that the electrostatic embedding provides several times of decrease in the difference of energies of testing and reference calculations in comparison with the conventional elongation approach (ELG). The mechanical embedding is implemented in a combination of the conventional elongation method and the ONIOM approach. Moreover, it was demonstrated that the geometry optimization with the ELG-IMEE reduces the errors in the optimized structures by about one order in root-mean-square deviation, when compared to ELG. 相似文献
95.
Manuel G. Ricardo Ameena M. Ali Jacek Plewka Ewa Surmiak Beata Labuzek Constantinos G. Neochoritis Jack Atmaj Lukasz Skalniak Ran Zhang Tad A. Holak Matthew Groves Daniel G. Rivera Alexander Dmling 《Angewandte Chemie (International ed. in English)》2020,59(13):5235-5241
Stapled peptides are chemical entities in‐between biologics and small molecules, which have proven to be the solution to high affinity protein–protein interaction antagonism, while keeping control over pharmacological performance such as stability and membrane penetration. We demonstrate that the multicomponent reaction‐based stapling is an effective strategy for the development of α‐helical peptides with highly potent dual antagonistic action of MDM2 and MDMX binding p53. Such a potent inhibitory activity of p53‐MDM2/X interactions was assessed by fluorescence polarization, microscale thermophoresis, and 2D NMR, while several cocrystal structures with MDM2 were obtained. This MCR stapling protocol proved efficient and versatile in terms of diversity generation at the staple, as evidenced by the incorporation of both exo‐ and endo‐cyclic hydrophobic moieties at the side chain cross‐linkers. The interaction of the Ugi‐staple fragments with the target protein was demonstrated by crystallography. 相似文献
96.
Jacek Lipok Tomasz Cierpicki Paweł Kafarski 《Phosphorus, sulfur, and silicon and the related elements》2013,188(6-7):1657-1660
Alternaria sp. isolated from the surface of carrot ( Daucus carota ) seeds appeared to be able to degrade amino-(4-methoxyphenyl)-methanephosphonic acid using it as a sole source of carbon, nitrogen, and phosphorus for growth. 相似文献
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100.
Vladislav S. Olkhovsky Vittoria Petrillo Jacek Jakiel Wiesław Kantor 《Central European Journal of Physics》2008,6(1):122-127
The particle tunneling through a 3-D rectangular potential barrier has been studied. The simplest model for multiple internal
reflections has been assumed. The explicit expression for all the transmission and reflection probability amplitudes have
been derived, as well as the tunneling and reflection phase times.
相似文献