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91.
Liliana Mititelu-Tartau Maria Bogdan Daniela Angelica Pricop Beatrice Rozalina Buca Ana-Maria Pauna Lorena Anda Dijmarescu Ana-Maria Pelin Liliana Lacramioara Pavel Gratiela Eliza Popa 《Molecules (Basel, Switzerland)》2021,26(13)
This paper is focused on the in vivo release and biocompatibility evaluation in rats of some novel systems entrapping zinc chloride in lipid vesicles. The particles were prepared by zinc chloride immobilization inside lipid vesicles made using phosphatidylcholine, stabilized with 0.5% chitosan solution, and dialyzed for 10 h to achieve a neutral pH. The submicrometric systems were physico-chemically characterized. White Wistar rats, assigned into four groups of six animals each, were treated orally with a single dose, as follows: Group I (control): deionized water 0.3 mL/100 g body weight; Group II (Zn): 2 mg/kg body weight (kbw) zinc chloride; Group III (LV-Zn): 2 mg/kbw zinc chloride in vesicles; Group IV (LVC-Zn): 2 mg/kbw zinc chloride in vesicles stabilized with chitosan. Haematological, biochemical, and immune parameters were assessed after 24 h and 7 days, and then liver fragments were collected for histopathological examination. The use of zinc submicrometric particles—especially those stabilized with chitosan—showed a delayed zinc release in rats. No substantial changes to blood parameters, plasma biochemical tests, serum complement activity, or peripheral neutrophils phagocytic capacity were noted; moreover, the tested substances did not induce liver architectural disturbances. The obtained systems provided a delayed release of zinc, and showed good biocompatibility in rats. 相似文献
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The kinetics of aromatic nucleophilic substitution of the nitric oxide‐generating diazeniumdiolate ion, DEA/NO, by thiols (L ‐glutathione, L ‐cysteine, DL ‐homocysteine, 1‐propanethiol, 2‐mercaptoethanol, and sodium thioglycolate) from the prodrug, DNP‐DEA/NO, has been examined in aqueous solution and in solutions of cationic DOTAP vesicles. Second‐order rate constants in buffered aqueous solutions (kRS‐ = 3.48–30.9 M?1 s?1; 30 °C) gave a linear Brønsted plot (βnuc = 0.414 ± 0.068) consistent with the rate‐limiting SNAr nucleophilic attack by thiolate ions. Cationic DOTAP vesicles catalyze the thiolysis reactions with rate enhancements between 11 and 486‐fold in Tris‐HCl buffered solutions at pH 7.4. The maximum rate increase was obtained with thioglycolate ion. Thiolysis data are compared to data for nucleophilic displacement by phenolate (kPhO‐ = 0.114 M?1 s?1) and hydroxide (kOH‐ = 1.82 × 10?2 M?1 s?1, 37 °C) ions. The base hydrolysis reaction is accelerated by CTAB micelles and DODAC vesicles, with the vesicles being ca 3‐fold more effective as catalysts. Analysis of the data using pseudo‐phase ion‐exchange (PIE) formalism implies that the rate enhancement of the thiolysis and base hydrolysis reactions is primarily due to reactant concentration in the surfactant pseudo‐phase. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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Jing Sui Lijuan Zhang Jadranka Travas-Sejdic Paul A. Kilmartin 《Macromolecular Symposia》2010,290(1):107-114
Summary: Hollow microspheres of PEDOT (poly(3,4-ethylenedioxythiophene) ranging from 0.5 to 10 µm have been synthesized by chemically oxidative polymerization of EDOT(3,4-ethylenedioxythiophene) using ammonium persulfate in a catanionic surfactant solution obtained by mixing cetyltrimethylammonium bromide (CTAB) and sodium dodecylbenzenesulfonate (SDBS). The effect of the molar ratio of CTAB to SDBS on the morphology of the PEDOT oxidation products has been investigated using SEM and TEM and by an analysis of the structural properties using UV-visible, FTIR and Raman spectroscopies, elemental analysis and conductivity measurements. The electro-catalytic activity of PEDOT hollow microspheres for the oxidation of ascorbic acid was investigated by cyclic voltammetry in a pH 6 citrate/phosphate buffer solution and compared to the activity of granular PEDOT particles formed in the absence of the catanionic surfactant. 相似文献
98.
H. Koibuchi 《The European Physical Journal B - Condensed Matter and Complex Systems》2008,66(1):85-90
A compartmentalized surface model of Nambu and Goto is studied on triangulated spherical surfaces by using the canonical Monte
Carlo simulation technique. One-dimensional bending energy is defined on the skeletons and at the junctions, and the mechanical
strength of the surface is supplied by the one-dimensional bending energy defined on the skeletons and junctions. The compartment
size is characterized by the total number L′ of bonds between the two-neighboring junctions and is assumed to have values in the range from L′ = 2 to L′ = 8 in the simulations, while that of the previously reported model is characterized by L′ = 1, where all vertices of the triangulated surface are the junctions. Therefore, the model in this paper is considered to
be an extension of the previous model in the sense that the previous model is obtained from the model in this paper in the
limit of L′↦1. The model in this paper is identical to the Nambu-Goto surface model without curvature energies in the limit of L′↦∞ and hence is expected to be ill-defined at sufficiently large L′. One remarkable result obtained in this paper is that the model has a well-defined smooth phase even at relatively large
L′ just as the previous model of L′↦ 1. It is also remarkable that the fluctuations of surface in the smooth phase are crucially dependent on L′; we can see no surface fluctuation when L′≤ 2, while relatively large fluctuations are seen when L′≥ 3. 相似文献
99.
Debye-Hückel theory of mixed charged-zwitterionic lipid layers 总被引:1,自引:0,他引:1
100.
Finken R Lamura A Seifert U Gompper G 《The European physical journal. E, Soft matter》2008,27(3):309-321
The stochastic motion of a two-dimensional vesicle in linear shear flow is studied at finite temperature. In the limit of
small deformations from a circle, Langevin-type equations of motion are derived, which are highly nonlinear due to the constraint
of constant perimeter length. These equations are solved in the low-temperature limit and using a mean-field approach, in
which the length constraint is satisfied only on average. The constraint imposes non-trivial correlations between the lowest
deformation modes at low temperature. We also simulate a vesicle in a hydrodynamic solvent by using the multi-particle collision
dynamics technique, both in the quasi-circular regime and for larger deformations, and compare the stationary deformation
correlation functions and the time autocorrelation functions with theoretical predictions. Good agreement between theory and
simulations is obtained. 相似文献