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排序方式: 共有500条查询结果,搜索用时 15 毫秒
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Tien Song Hiep Pham Shinichi Hasegawa Peter Mahon Katia Guérin Marc Dubois Aimin Yu 《Electroanalysis》2022,34(3):435-444
Three reduced graphene oxide nanocomposites were employed to achieve the simultaneous electrochemical determination of multi-drugs including acetaminophen (ACTM), carbendazim (CB) and ciprofloxacin (CFX). All nanocomposite modified electrodes showed improved current responses for three drugs. Notably cauliflower-like platinum nanoparticles decorated reduced graphene oxide modified electrode (or Pt−RGO/GCE) exhibited the best performance in terms of electrochemical stability. Using Pt−RGO/GCE, the linear detect ranges of 30–120 μM, 25–115 μM and 10–25 μM, and detection limit values of 3.49, 2.96, and 1.53 μM were achieved for ACTM, CB and CFX respectively. The electrode was further used for the successful determination of above drugs in tap and river water using differential pulse voltammetry. From the obtained results, we believe that Pt-RGO/GCE is highly promising for the fabrication of robust electrochemical sensors for simultaneously determining ACTM, CB and CFX or similar types of drugs in the future. 相似文献
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Nguyen Tien A. Berezhnaya M. V. Pham Thanh L. Mittova V. O. Vo Mai Q. Nguyen Linh T. Tr. Do Huong Tr. Mittova I. Ya. Viryutina E. L. 《Russian Journal of Applied Chemistry》2019,92(4):498-504
Russian Journal of Applied Chemistry - Nanopowders of neodymium ferrite with perovskite structure were synthesized by co-precipitation precipitation via hydrolysis of iron(III) and neodymium(III)... 相似文献
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Huu-Hung Nguyen Thi-Phuong Nguyen Nguyen Tien Trung Cam-Tu D. Phan Thi-Bich-Ngoc Dao Dinh-Tri Mai Jirapast Sichaem Ngoc-Hong Nguyen Cong-Luan Tran Thuc-Huy Duong 《Arabian Journal of Chemistry》2021,14(7):103189
Two new cycloartanes, combretanones G and H (1 and 2), were isolated from the leaves of Combretum quadrangulare. Their structures were elucidated by applying a set of spectroscopic methods, while their relative configurations were determined using DFT-NMR chemical shift calculations and subsequent assignment of DP4 probabilities. Compounds 1 and 2 are C-23/C-24 stereoisomers of the previously-reported euphonerin E. Both exhibited moderate cytotoxicity against three human cancer cell lines. Compound 2 was shown to be a potent antiparasitic. Our results confirm the traditional medicinal uses of Combretum quadrangulare in Vietnam. 相似文献
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Nadya Abbood Dr. Tien Duy Vo Dr. Jonas Watzel Dr. Kenan A. J. Bozhueyuek Prof. Dr. Helge B. Bode 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(26):e202103963
Bacterial natural products in general, and non-ribosomally synthesized peptides in particular, are structurally diverse and provide us with a broad range of pharmaceutically relevant bioactivities. Yet, traditional natural product research suffers from rediscovering the same scaffolds and has been stigmatized as inefficient, time-, labour- and cost-intensive. Combinatorial chemistry, on the other hand, can produce new molecules in greater numbers, cheaper and in less time than traditional natural product discovery, but also fails to meet current medical needs due to the limited biologically relevant chemical space that can be addressed. Consequently, methods for the high throughput generation of new natural products would offer a new approach to identifying novel bioactive chemical entities for the hit to lead phase of drug discovery programs. As a follow-up to our previously published proof-of-principle study on generating bipartite type S non-ribosomal peptide synthetases (NRPSs), we now envisaged the de novo generation of non-ribosomal peptides (NRPs) on an unreached scale. Using synthetic zippers, we split NRPSs in up to three subunits and rapidly generated different bi- and tripartite NRPS libraries to produce 49 peptides, peptide derivatives, and de novo peptides at good titres up to 145 mg L−1. A further advantage of type S NRPSs not only is the possibility to easily expand the created libraries by re-using previously created type S NRPS, but that functions of individual domains as well as domain-domain interactions can be studied and assigned rapidly. 相似文献
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Po‐Yeng Feng Yi‐Hung Liu Prof. Tien‐Sung Lin Prof. Shie‐Ming Peng Prof. Ching‐Wen Chiu 《Angewandte Chemie (International ed. in English)》2014,53(24):6237-6240
Chemical reduction of a hydroxyphenyl‐substituted borane triggers a sequential electron‐ and intramolecular hydrogen‐atom‐transfer process to afford a hydridoborate phenoxide dianion. On the other hand, hydrogen‐atom abstraction of the borane leads to the isolation of a neutral borylated phenoxyl radical, which can be transformed to the corresponding benzoquinone borataalkene derivative by reduction with cobaltocene. 相似文献
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Super elastic nitinol (NiTi) wires were exploited as highly robust supports for three distinct crosslinked polymeric ionic liquid (PIL)-based coatings in solid-phase microextraction (SPME). The oxidation of NiTi wires in a boiling (30% w/w) H2O2 solution and subsequent derivatization in vinyltrimethoxysilane (VTMS) allowed for vinyl moieties to be appended to the surface of the support. UV-initiated on-fiber copolymerization of the vinyl-substituted NiTi support with monocationic ionic liquid (IL) monomers and dicationic IL crosslinkers produced a crosslinked PIL-based network that was covalently attached to the NiTi wire. This alteration alleviated receding of the coating from the support, which was observed for an analogous crosslinked PIL applied on unmodified NiTi wires. A series of demanding extraction conditions, including extreme pH, pre-exposure to pure organic solvents, and high temperatures, were applied to investigate the versatility and robustness of the fibers. Acceptable precision of the model analytes was obtained for all fibers under these conditions. Method validation by examining the relative recovery of a homologous group of phthalate esters (PAEs) was performed in drip-brewed coffee (maintained at 60 °C) by direct immersion SPME. Acceptable recoveries were obtained for most PAEs in the part-per-billion level, even in this exceedingly harsh and complex matrix. 相似文献