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排序方式: 共有321条查询结果,搜索用时 15 毫秒
61.
Eva Garrido Dr. María Alfonso Dr. Borja Díaz de Greñu Beatriz Lozano-Torres Dr. Margarita Parra Dr. Pablo Gaviña Dr. M. Dolores Marcos Prof. Ramón Martínez-Máñez Dr. Félix Sancenón 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(13):2813-2816
This work reports the synthesis, characterization, and sensing behavior of a hybrid nanodevice for the detection of the potent abuse drug 25I-NBOMe. The system is based on mesoporous silica nanoparticles, loaded with a fluorescent dye, functionalized with a serotonin derivative and capped with the 5-HT2A receptor antibody. In the presence of 25I-NBOMe the capping antibody is displaced, leading to pore opening and rhodamine B release. This delivery was ascribed to 5-HT2A receptor antibody detachment from the surface due to its stronger coordination with 25I-NBOMe present in the solution. The prepared nanodevice allowed the sensitive (limit of detection of 0.6 μm ) and selective recognition of the 25I-NBOMe drug (cocaine, heroin, mescaline, lysergic acid diethylamide, MDMA, and morphine were unable to induce pore opening and rhodamine B release). This nanodevice acts as a highly sensitive and selective fluorometric probe for the 25I-NBOMe illicit drug in artificial saliva and in sweets. 相似文献
62.
Claudio Parra Emilio Soto Gloria León Cristian O. Salas Michael Heinrich Carlos Echiburú-Chau 《Natural product research》2018,32(6):719-722
Continuing with our study characterising Senecio nutans Sch. Bip., we have isolated and identified a simple coumarin, scopoletin, that could be relevant for the biological properties of the species related with the ancestral medical uses. This is the first report of scopoletin from S. nutans. In addition, the extract was analysed for its antioxidant activity using the ABTS and FRAP method as well as providing the first nutritional analyses of this plant from northern Chile highlands. 相似文献
63.
Solubilization of phospholipid bilayers by C14-alkyl betaine/anionic mixed surfactant systems 总被引:1,自引:0,他引:1
The mechanisms governing the solubilizing interactions between zwitterionic/anionic mixed surfactant systems at different molar fractions of the zwitterionic surfactant (X
zwitter) and unilamellar liposomes were investigated. Solubilization was detected as a decrease in static lightscattering of liposome suspensions. Three parameters were regarded as corresponding to the effective surfactant/lipid molar ratios (Re) at which the surfactant system a) saturated the liposomesRe
sat; b) resulted in 50% solubilization of liposomesRe
50%, and c) led to a complete solubilization of these structuresRe
sol. These parameters corresponded to theRe at which light scattering stars to decrease, reaches 50% of the original value and shows no further decrease. From these parameters the surfactant partition coefficients for these three steps (K
sat,K
50% andK
sol) were also determined. The mixed systems were formed byN-tetradecyl-N, N-dimethylbetaine (C14-Bet) and sodium dodecyl sulphate (SDS) in PIPES buffer at pH 7.20. Liposomes were formed by egg phosphatidylcholine and phosphatidic acid (9:1 molar ratio). When the range ofX
zwitter was about 0.4–0.6Re andK parameters showed a maximum, whereas the critical micelle concentration (CMC) of these systems exhibited a minimum. Given that the ability of the surfactant systems to solubilize liposomes is inversely related toRe
sol, this capacity appeared to be directly correlated with the CMC of the systems. The progressive rise ofK during the process indicates that an increasing surfactant partition equilibrium governs the interaction process from the saturation until the solubilization of vesicles, the free surfactant concentration remaining almost constant with similar values to the CMC for each mixed system studied. 相似文献
64.
A potentiometric permanganate titration has been developed for the determination of hydrogen peroxide in the presence of fluoride, as well as of the peroxide content in the titanium—fluoride—peroxide mixed complex. It is based on the stabilization of manganese(III) with an excess of fluoride in a moderately acidic medium (pH close to 3) and on the use of iron(III) as catalyst. Errors are less than 0.5%. 相似文献
65.
J. Alderete J. Belmar M. Parra C. Zúñiga Corresponding author V. Jimenez 《Liquid crystals》2013,40(11):1319-1325
The synthesis and liquid crystalline properties of a new series of calamitic liquid crystals containing 4-H-benzopyran-4-one (chromone) within the central core is reported. The first homologue in the series display SmA phase (8a), the homologues (8b–e) exhibit SmA and SmC mesophases and the homologues (8f–h) exhibit only a SmC mesophase. 相似文献
66.
Ana M. Costero Ursula Llaosa Salvador Gil Margarita Parra Manuel Colera 《Tetrahedron: Asymmetry》2009,20(13):1468-1471
Two new cyclohexane-based thiourea chiral ligands have been synthesized in their enantiomerically pure forms. Both the ability of these ligands in the complexation of chiral dicarboxylates and their sensing properties have been studied. The influence of the stoichiometry of the formed complexes on the fluorescent properties of the systems has been established. The effect of additional substitution in the cyclohexyl moiety was considered by comparing the properties of the newly prepared ligands with those of similar compounds previously described. 相似文献
67.
68.
Combined parametric optimization of P3HT: PC70BM films for efficient bulk-heterojunction solar cells
Siddiqui Hafsa Parra Mohammad Ramzan Pandey Padmini Qureshi M. S. Haque Fozia Zia 《Journal of Solid State Electrochemistry》2019,23(12):3267-3274
Journal of Solid State Electrochemistry - In this report, the effects of photoactive blend compositions, film thicknesses, and annealing conditions on the P3HT:PC70BM solar cells performance and... 相似文献
69.
Two homologous series of esters derived from Schiff's bases containing the 1,3,4-thiadiazole unit (series 3 and 5) were synthesized and their liquid crystalline properties investigated by optical microscopy and differential scanning calorimetry. Depending on the position occupied by the carbonyl group, the smectic A phase was observed in series 3 and nematic phase in series 5. 相似文献
70.