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51.
Adrian Pîrnău Mihaela Mic Mircea Bogdan Ioan Turcu 《Journal of inclusion phenomena and macrocyclic chemistry》2014,79(3-4):283-289
The inclusion of local anesthetic drug procaine hydrochloride by β-cyclodextrin was investigated by 1D and 2D proton NMR spectroscopy and isothermal titration calorimetry (ITC) at 298 K. The stoichiometry of the complex was determinate by the method of continuous variation, using the chemical induced shift of both host and guest protons. The association constant K, of the obtained complex was calculated and found to be 293.17 M?1. Rotating frame NOE spectroscopy, was used to ascertain the solution geometry of the host–guest complex. The result reveals that the procaine molecule penetrates into the β-cyclodextrin cavity with the aromatic ring. The energetics of complexation process is investigated by ITC technique. The analysis indicates that the complexation of procaine by β-CD is an exothermic process and show that both enthalpy and entropy contribute to the binding process. The obtained value for the association constant is in good agreement with that obtained from NMR. 相似文献
52.
Croitor Lilia Petric Mihaela F. Vlase Gabriela Vlase Titus Siminel Anatolii V. Bourosh Paulina N. Crisan Manuela E. 《Journal of Thermal Analysis and Calorimetry》2020,141(3):973-979
Journal of Thermal Analysis and Calorimetry - Acid–base multicomponent systems based on active pharmaceutical ingredients 2-chloro-5-nitrobenzoic acid (2Cl5NBH) and monoethanolamine were... 相似文献
53.
Alyssa B. Sanders Jacob T. Zangaro Nakoa K. Webber Ryan P. Calhoun Elizabeth A. Richards Samuel L. Ricci Hannah M. Work Daniel D. Yang Kaitlyn R. Casey Joseph C. Iovine Gabriela Baker Taylor V. Douglas Sierra B. Dutko Thomas J. Fasano Sarah A. Lofland Ashley A. Rajan Mihaela A. Vasile Benjamin R. Carone Nathaniel V. Nucci 《Molecules (Basel, Switzerland)》2022,27(5)
Despite considerable advances in recent years, challenges in delivery and storage of biological drugs persist and may delay or prohibit their clinical application. Though nanoparticle-based approaches for small molecule drug encapsulation are mature, encapsulation of proteins remains problematic due to destabilization of the protein. Reverse micelles composed of decylmonoacyl glycerol (10MAG) and lauryldimethylamino-N-oxide (LDAO) in low-viscosity alkanes have been shown to preserve the structure and stability of a wide range of biological macromolecules. Here, we present a first step on developing this system as a future platform for storage and delivery of biological drugs by replacing the non-biocompatible alkane solvent with solvents currently used in small molecule delivery systems. Using a novel screening approach, we performed a comprehensive evaluation of the 10MAG/LDAO system using two preparation methods across seven biocompatible solvents with analysis of toxicity and encapsulation efficiency for each solvent. By using an inexpensive hydrophilic small molecule to test a wide range of conditions, we identify optimal solvent properties for further development. We validate the predictions from this screen with preliminary protein encapsulation tests. The insight provided lays the foundation for further development of this system toward long-term room-temperature storage of biologics or toward water-in-oil-in-water biologic delivery systems. 相似文献
54.
Physics of Atomic Nuclei - The formalism of asymptotic normalization coefficients and methods for determining them from experimental nuclear data are discussed. A new method is proposed that uses... 相似文献
55.
Mihai Răducă Cristian D. Ene Sorana Ionescu Mihaela Florea 《Journal of Coordination Chemistry》2019,72(8):1222-1237
Abstract1-D coordination polymers, 1∞[Zn(fl)2]·2EtOH and 1∞[Zn(fl)2]·2MeOH, and a dinuclear complex, [{Zn(fl)2}2(dienpip)]·4H2O·4EtOH (dienpip?= N,N′-bis(2-aminoethyl)piperazine), were obtained using Zn(II) ions and fluorescein anions (fl). Thermal analysis shows stability of the polymers after solvent removal up to more than 400?°C. Crystallization solvent molecules were removed under reduced pressure with the preservation of the polymeric structure, 1∞[Zn(fl)2]. Desolvated crystals were exposed to I2 vapors and the crystal structure determination by X-ray diffraction confirmed the presence of I2 molecules in the channels generated in crystals by the metal-organic framework. The iodine content, evaluated by X-ray diffraction, corresponds to the overall formula 1∞[Zn(fl)2]·0.3I2. The optical properties of the coordination polymers and the dinuclear complex have been investigated. 相似文献
56.
Electrochemical Behaviour and Rapid Determination of L‐Dopa at Electrochemically Pretreated Screen Printed Carbon Electrode
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Andreea Alexandra Rabinca Mihaela Buleandra Adriana Balan Ioan Stamatin Anton Alexandru Ciucu 《Electroanalysis》2015,27(10):2275-2279
A simple and rapid voltammetric method based on a disposable electrochemically pretreated screen‐printed carbon electrode is proposed for the determination of L ‐dopa. Under optimum differential pulse voltammetry conditions a limit of detection of 3.6×10?7 M for L ‐dopa was obtained. The method was successfully applied to the determination of L ‐dopa in a commercial pharmaceutical formulation. 相似文献
57.
Mihaela Badea Rodica Olar Dana Marinescu Gina Vasile 《Journal of Thermal Analysis and Calorimetry》2008,92(1):209-214
A series of new complexes with mixed ligands of the type [ML(C3H3O2)2]·nH2O (((1)
M=Mn, n=1; (2)
M=Co(II), n=2; (3)
M=Ni(II), n=4; (4)
M=Cu(II), n=1.5; (5)
M=Zn(II), n=0; L=3-amino-1,2,4-triazole and (C3H3O2)=acrylate anion) were synthesized and characterised by chemical analysis and IR data. In all complexes the 3-amino-1,2,4-triazole
acts as bridge while the acrylate acts as bidentate ligand except for complex (5) where it is found as unidentate. The thermal behaviour steps were investigated in nitrogen flow. The thermal transformations
are complex processes according to TG and DTG curves including dehydration, acrylate ion and 3-amino-1,2,4-triazole degradation
respectively. The final products of decomposition are the most stable metal oxides, except for complex (4) that leads to metallic copper. 相似文献
58.
Y. Al-Angry S. Savin K. E. Rammutla M. J. Pooley E. R. H. Van Eck A. V. Chadwick 《辐射效应与固体损伤》2013,168(1-6):209-213
A problem in the study of nanoparticles is that they will tend to grow at moderate temperatures. For example, most oxides (e.g. SnO2, ZrO2, MgO) will show significant grain growth at 400°C. This severely limits experimental studies that require measurements over an extensive temperature range. In this contribution we demonstrate that the incorporation of A12O3, can significantly restrict grain growth in MgO and ZrO2 even at high temperatures. 相似文献
59.
M. D. Bondar’kov D. M. Bondar’kov A. M. Maksimenko V. A. Zheltonozhskii M. V. Zheltonozhskaya V. V. Petrov A. I. Savin 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(2):261-265
The content of the isotopes 3H, 14C, 36Cl, 55Fe, 59Ni, 63Ni, 60Co, 90Sr, 93m
Nb, 108Ag, 133Ba, 134Cs, 137Cs, 154Eu, and 155Eu in the GRP-2-125 graphite from the reactor of Power Unit 2 at the Chernobyl Nuclear Power Plant was measured. The results
were compared with the calculations and literature data. Some regularities and correlations were revealed in the content of
various radionuclides in graphite. Graphite porosity and desorption of radionuclides from graphite were studied.
Original Russian Text ? M.D. Bondar’kov, D.M. Bondar’kov, A.M. Maksimenko, V.A. Zheltonozhskii, M.V. Zheltonozhskaya, V.V.
Petrov, A.I. Savin, 2009, published in Izvestiya Rossiiskoi Akademii Nauk. Seriya Fizicheskaya, 2009, Vol. 73, No. 2, pp.
274–278. 相似文献
60.
K. V. Goncharenko S. S. Savin V. I. Tishkov 《Moscow University Chemistry Bulletin》2010,65(3):131-134
A method for the detection of nanogram amounts of formate dehydrogenase on membranes was developed. The optimization of the
method was carried out for determination of the best mediator concentration and tetranitrotetrazolium blue. It was found that
5-methyl-phenazil methosulfate is a more effective mediator than phenazine methosulfate. Different types of membranes were
tested and it was shown that nitrocellulose membrane provides a low background and the highest sensitivity. Under optimal
conditions the detection limit was 15 ng of the enzyme in the probe. 相似文献