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111.
de Farias Davi Marques de Faria Lucas Vinícius Lisboa Thalles Pedrosa Matos Maria Auxiliadora Costa Muñoz Rodrigo Alejandro Abarza Matos Renato Camargo 《Journal of Solid State Electrochemistry》2020,24(5):1165-1173
Journal of Solid State Electrochemistry - In this paper, we compare reduced graphene oxide (RGO) electrode with multi-walled carbon nanotubes (MWCNT) as modifiers for the sensitive detection of... 相似文献
112.
Alejandro Valverde Amira ben Hassine Vernica Serafín Cristina Muoz‐San Martín María Pedrero María Garranzo‐Asensio Maria Gamella Noureddine Raouafi Rodrigo Barderas Paloma Yez‐Sedeo Susana Campuzano Jos M. Pingarrn 《Electroanalysis》2020,32(4):706-714
This paper reports the development of a dual immunosensor using magnetic microcarriers (MBs) and amperometric transduction at dual screen‐printed carbon electrodes (SPdCEs) for the simultaneous determination of two biomarkers: interleukin‐13 receptor α2 (IL‐13Rα2) and E‐cadherin (E‐CDH), with both extracellular and soluble fraction; oncogenic and tumor suppressor markers, respectively, of great relevance in metastatic processes. The implemented methodology involved the formation of sandwich‐type immunocomplexes using specific capture antibodies immobilized onto carboxylic acid magnetic microbeads (HOOC‐MBs), and biotinylated detector antibodies labeled with streptavidin?horseradish peroxidase conjugates (Strep‐HRP). The amperometric detection was performed by addition of hydrogen peroxide in the presence of hydroquinone (HQ) as the redox mediator. The dual immunosensing platform provided linear calibration ranges suitable for the determination of both biomarkers in liquid and solid clinical specimens as well as excellent selectivity against other cancer biomarkers. This simple handling dual bioplatform was applied to the determination of the soluble and extracellular fraction of the target biomarkers in serum and paraffined‐embedded tissues from colorectal cancer (CRC) patients diagnosed at different tumor grade. The obtained results reveal great potential of this configuration to improve the reliability in diagnosing metastatic CRC. 相似文献
113.
Santana-Martínez Ivette Ramírez-Palma María Teresa Sánchez-Escalera Javier Martínez-Otero Diego García-Eleno Marco A. Dorazco-González Alejandro Cuevas-Yañez Erick 《Structural chemistry》2020,31(1):191-201
Structural Chemistry - Structural insights of a group of bi-1,2,3-triazoles derived from oxidative CuAAC are described through an X-ray crystallography study, distinguishing a dihedral angle which... 相似文献
114.
Ruben Canton‐Vitoria Tobias Scharl Anastasios Stergiou Alejandro Cadranel Raul Arenal Dirk M. Guldi Nikos Tagmatarchis 《Angewandte Chemie (International ed. in English)》2020,59(10):3976-3981
Molybdenum disulfide nanosheets covalently modified with porphyrin were prepared and fully characterized. Neither the porphyrin absorption nor its fluorescence was notably affected by covalent linkage to MoS2. The use of transient absorption spectroscopy showed that a complex ping‐pong energy‐transfer mechanism, namely from the porphyrin to MoS2 and back to the porphyrin, operated. This study reveals the potential of transition‐metal dichalcogenides in photosensitization processes. 相似文献
115.
Dr. Reiko Ueoka Dr. Roy A. Meoded Alejandro Gran‐Scheuch Dr. Agneya Bhushan Prof. Dr. Marco W. Fraaije Prof. Dr. Jörn Piel 《Angewandte Chemie (International ed. in English)》2020,59(20):7761-7765
Bacterial trans‐acyltransferase polyketide synthases (trans‐AT PKSs) are multimodular megaenzymes that biosynthesize many bioactive natural products. They contain a remarkable range of domains and module types that introduce different substituents into growing polyketide chains. As one such modification, we recently reported Baeyer–Villiger‐type oxygen insertion into nascent polyketide backbones, thereby generating malonyl thioester intermediates. In this work, genome mining focusing on architecturally diverse oxidation modules in trans‐AT PKSs led us to the culturable plant symbiont Gynuella sunshinyii, which harbors two distinct modules in one orphan PKS. The PKS product was revealed to be lobatamide A, a potent cytotoxin previously only known from a marine tunicate. Biochemical studies show that one module generates glycolyl thioester intermediates, while the other is proposed to be involved in oxime formation. The data suggest varied roles of oxygenation modules in the biosynthesis of polyketide scaffolds and support the importance of trans‐AT PKSs in the specialized metabolism of symbiotic bacteria. 相似文献
116.
117.
Muhammad Arshad M. Alejandro Fernández Eoghan M. McGarrigle Varinder K. Aggarwal 《Tetrahedron: Asymmetry》2010,21(13-14):1771-1776
The epoxidation of meroquinene aldehyde with a chiral sulfur ylide as the key step in the synthesis of quinine and quinidine is described. The epoxidation reactions proceed under reagent control with high selectivity and good yield. The effect of sulfide and ylide substituents on the stereochemical outcome of the reaction is discussed. 相似文献
118.
An integrated mechanical model for fiber-laden membranes is presented and representative predictions of relevance to cellulose
ordering and orientation in the plant cell wall are presented. The model describes nematic liquid crystalline self-assembly
of rigid fibers on an arbitrarily curved fluid membrane. The mechanics of the fluid membrane is described by the Helfrich
bending-torsion model, the fiber self-assembly is described by the 2D Landau-de Gennes quadrupolar Q-tensor order parameter model, and the fiber-membrane interactions (inspired by an extension of the 2D Maier-Saupe model to
curved surfaces) include competing curvo-philic (curvature-seeking) and curvo-phobic (curvature-avoiding) effects. Analysis
of the free energy reveals three fiber orientation regimes: (a) along the major curvature, (b) along the minor curvature,
(c) away from the principal curvatures, according to the competing curvo-philic and curvo-phobic interactions. The derived
shape equation (normal stress balance) now includes curvature-nematic ordering contributions, with both bending and torsion
renormalizations. Integration of the shape and nematic order equations gives a complete model whose solution describes the
coupled membrane shape/fiber order state. Applications to cylindrical membranes, relevant to the plant cell wall, shows how
growth decreases the fiber order parameter and moves the fibers’ director from the axial direction towards the azimuthal orientation,
eventually leading to a state of stress predicted by pure membranes. The ubiquitous 54.7° cellulose fibril orientation with
respect to the long axis in a cylindrical plant cell wall is shown to be predicted by the preset model when the ratio of curvo-phobic
and curvo-philic interactions is in the range of the cylinder radius. 相似文献
119.
120.