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31.
The research was conducted to know the effect of amikacin administrations to the concentration of drug in reptile. The 16 sanca batik snakes (Broghammerus reticulatus) were adapted then divided into four groups of which each was administered5 mg · kg–1 body weight of amikacin by posterior and anterior intravenous and intramuscular injection, respectively. The blood collection was done by cardio-puncture to each group at minute 1, 60 and 24, 48 h after drug injection and the drug concentration was analysed by High Performance Liquid Chromatography. The result showed that the drug by i.v. or i.m. administration routes (t1,t48) from posterior region had higher concentrations (81.90 ± 23.1) mg · mL–1, (17.23 ± 5.29) mg · mL–1) compared to the anterior injection (P < 0.01). The other concentration comparisons between regions resulted in no significant difference. 相似文献
32.
《Arabian Journal of Chemistry》2022,15(2):103586
A series of metal ion complexes was prepared in solid state from Cu(II), Hg(II) and UO2(II) ions with 3-oxo-3-(2-(2-oxoindolin-3-ylidene)hydrazineyl)-N-phenylpropanamide (H3L) ligand through solvent free synthesis methodology. The chemical formulae of the new compounds were estimated according to variable spectral and analytical investigations. The ligand exhibited a neutral or mononegative tetradentate mode of coordination towards the central ions inside the octahedral arrangement that proposed for the three complexes. The DFT/B3LYP method was applied under different basis sets (6-31G*or SDD) to optimize the structures of new compounds except the UO2(II) complex. The computational data were investigated to verify the binding mode that suggested spectrally. Moreover, studies in solution regarding Cu(II) ion via cyclic voltammetry were performed in absence or presence of H3L, to realize the significant effect of complex formation on the electrochemical manners of copper. The shifts in the potential peaks accompanied by the changes in the values of parameters correspond to kinetic and thermodynamic. Also, the solvation and kinetic characteristics for the cathodic and anodic potential of Cu(II) ion in absence or presence of H3L at different scan rates, were estimated. Finally, the ligand and copper ion exhibited high affinity towards complexation in solution. Furthermore, the activity of the new compounds towards inhibiting microbes was studied against Staphylococcus aureus (G+) and Escherichia coli (G-) bacteria as well as Candida albicans (fungus) by determining the inhibition zone diameter. Also, both the antioxidant and cytotoxic activity of the isolated compounds were evaluated. Commonly, a remarkable antimicrobial and anticancer activity was appeared with UO2(II) complex and the ligand. While, the antioxidant activity of all compounds appeared lower. 相似文献
33.
《Arabian Journal of Chemistry》2022,15(5):103758
This work suggests a green method for synthesizing Au nanoparticles (AuNPs) using the aqueous extract of Salix aegyptiaca extract. The mechanism of green synthesized AuNPs was examined by molecular electrostatic potential (MEP) calculations. AuNPs were characterized with different techniques such as Ultraviolet–visible spectroscopy (UV–vis), Fourier-transform infrared spectroscopy (FT-IR) spectroscopy, X-ray diffraction (XRD), and Transmission electron microscopy (TEM). Electrochemical investigation of modified glassy carbon electrode using AuNPs (AuNPs/GCE) shows that the electronic transmission rate between the modified electrode and [Fe (CN)6]3?/4? increased. Process of oxidation, energy gap, and chemical reactivity indexes of the (+)-epicatechin (2S,3S) were investigated using electrochemical techniques (cyclic voltammetry (CV) and differential pulse voltammetry (DPV) as well as UV–Visible spectroscopy and compared with quantum mechanical calculations. DPV and CV were used to obtain HOMO energies of the (+)-epicatechin (2S,3S), an optical energy gap was obtained from the UV–Vis spectroscopy. Frontier molecular orbitals analysis (FMO) and reactivity indexes such as chemical hardness (?), electrophilicity (?), electronic chemical potential (μ), electron acceptor power (?+), electron donor power (??) were determined with functional theory (DFT) calculations. In summary, the HOMO energy obtained from the experimental analyses (EHOMO (from DPV) = -5.24 eV, and EHOMO (from CV) = -5.28 eV) has a relative agreement with the HOMO energy calculated by B3LYP/6–31 g (d, p) including the solvent effect (water) (EHOMO (from B3LYP) = -5.75 eV). Also, UV–Vis spectroscopy gives the bandgap energy equal to 4.31 eV, while the 4.13 eV is calculated by TD-DFT-b3lyp/6–31 + g(d). 相似文献
34.
《Arabian Journal of Chemistry》2022,15(7):103876
Knowledge of drug solubility data in supercritical carbon dioxide (SC-CO2) is a fundamental step in producing nano and microparticles through supercritical fluid technology. In this work, for the first time, the solubility of metoclopramide hydrochloride (MCP) in SC-CO2 was measured in pressure and temperature range of 12 to 27 MPa and 308 to 338 K, respectively. The results represented a range mole fractions of 0.15 × 10-5 to 5.56 × 10-5. To expand the application of the obtained data, six semi-empirical models and three models based on the Peng-Robinson equation of state (PR + VDW, PR + WS + Wilson and PR + MHV1 + COSMOSAC) with different mixing rules and various ways to describe intermolecular interactions were investigated. Furthermore, total enthalpy, sublimation enthalpy and solvation enthalpy relevant to MCP solvating in SC-CO2 were estimated. 相似文献
35.
《Arabian Journal of Chemistry》2022,15(11):104225
Cinnamomum camphora leaf essential oil (CEO) was extracted using enzymatic-ultrasound pretreatment followed by microwave assisted extraction (EUP-MAE) method and simultaneously studied as a mycelial growth inhibitor against five important pathogens which cause potato dry rot. The optimum EUP-MAE conditions with a real CEO yield of 19.23 ± 0.12 mg/g were obtained through Plackett–Burman design and Box–Behnken design as follows: 3 % of enzyme dosage, 2 h of pretreatment time, 5 of pH, 210 W of ultrasound power, 50 °C pretreatment temperature, 16 mL/g of water to solid ratio, 30 min of microwave time and 500 W of microwave power. Compared to the reference methods, EUP-MAE possessed a highest CEO yield than these of ultrasound-microwave assisted extraction (U-MAE) and traditional hydrodistillation (HD). Gas chromatography-mass spectrometry (GC–MS) analysis demonstrated that eucalyptol, camphor, and α-terpineol were the three main constituents of CEO. Results from in vitro antifungal activity assay revealed that the mycelial growths of all the five tested Fusarium solani, Fusarium culmorum, Fusarium trichothecioides, Fusarium sporotrioides, and Fusarium avenaceum were apparently affected by CEO. These findings not only provide a potential paradigm for the separation of plant essential oil, but also guarantee a promising utilization of the CEO for potato protection to control the Fusarium spp. 相似文献
36.
《Arabian Journal of Chemistry》2022,15(12):104337
Indisputable importance of drug solubility in various industrial perspectives has motivated the scientists to evaluate different techniques to improve it. Fenoprofen is a significant nonsteroidal anti-inflammatory drug (NSAID), that is the orally administered to relieve mild to moderate pain and the unfavorable symptoms of osteoarthritis and rheumatoid arthritis (i.e., inflammation and stiffness). Supercritical fluids (SCFs) belong to a certain type of fluids, in which their temperature and pressure are higher than the critical point. This property allows the CO2SCF to simultaneously possess the characteristics of both a liquid and a gas. The prominent target of this paper is to mathematically develop three predictive models via machine learning (ML) technique to optimize the solubility of Fenoprofen in CO2SCF. In this study, we have 32 data vectors in each dataset, including two input features of pressure and temperature. The output target is solubility, which we are going to model and analyze. Models are constructed through the use of Modular ANN (MANN), Gaussian processes regression (GPR), and the K-Nearest Neighbor technique (KNN) in this body of work. The glowworm swarm optimization (GSO) swarm-based method is utilized in order to carry out the process of model optimization. The root mean squared error (RMSE) rates for GSO-KNN, GSO-MANN, and GSO-GPR are respectively 5.25E-04, 5.46E-04, and 3.01E-05. The aforementioned models were also judged according to a number of other criteria, and since the GSO-GPR model was found to be the most effective according to all of these standards, it is being treated as the conclusive model of this investigation. In addition, the maximum error has been brought down to 5.02E-05 with the help of this model, which has an R2-score of 0.999. 相似文献
37.
Electropolymerization is one of the most important methodologies to synthesize and develop conducting polymers. The complexity of the polymerization mechanism, ion doping processes and structural defects are considered to be symbiotic and unavoidable, making the stagnant state and huge band gap with advanced interdisciplinary research fields and important applications in the last three decades. Herein, we provide a point of view into controlled electropolymerization by regioselective activation reactions of monomers, where self-dimerizations instead of self-electropolymerizations were utilized. The resulting dimers play a role in the connections between functional building blocks to form functional polymers on demand. This account highlights the typical findings in controlled electropolymerizations as a forum for discussing new opportunities in exploiting novel designs and applications. 相似文献
38.
Stefan Fritsch Nazli Aldemir Jan Balszuweit Kevin Bojaryn Prof. Dr. Jens Voskuhl Dr. Christoph Hirschhäuser 《ChemistryOpen》2022,11(7):e202200098
The first total synthesis of resveratrone and iso-resveratrone based on an epoxide olefination approach is described. The pivotal reaction proceeds by insertion of the lithiated epoxide into a boronic ester and subsequent syn-elimination. Resveratrone has been described to have remarkable photophysical properties, including two-photon absorption. Therefore, an azide derivative has been prepared to allow for use as a biological label. 相似文献
39.
Alena Shlyaykher Marvin Ehmann Dr. Antti J. Karttunen Dr. Frank Tambornino 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(54):13552-13557
The full series of quasibinary alkali-metal selenocyanates was synthesized either by oxidation of the respective cyanides (A=Li−Rb) or by metathesis (A=Cs). For Li[SeCN] only ball-milling and subsequent annealing led to the isolation of the quasibinary selenocyanate. Their structures were refined from single-crystal and powder X-ray data. The respective solid-state IR and Raman spectra were interpreted with the aid of solid-state quantum-mechanical calculations and DSC-TGA measurements allowed for extraction of melting points. Only for Li[SeCN] a possible phase transition was observed that is discussed on the basis of VT-PXRD experiments. It is also the only quasibinary selenocyanate to form a hydrate (Li[SeCN] ⋅ 2H2O). 相似文献
40.
Zhiguo Lu Xiangyu Wang Tianlu Zhang Luyao Zhang Jun Yang Yan Li Jie Shen Jianze Wang Yunwei Niu Zuobing Xiao Guiying Liu Xin Zhang 《中国化学快报》2021,31(12):3139-3142
Silk has been widely used in the clothing industry due to their soft and smooth features, good biocompatibility, good heat dissipation, warmth and ultraviolet resistance. The application of fragrance to silk can significantly improve the performance of silk. However, there are two key scientific problems that need to be solved: slowing down the release rate of fragrances and increasing the scent lasting time of silk. In this study, cationic and temperature-sensitive liposomes were designed and prepared to encapsulate eugenol. These fragrance-loaded liposomes significantly slowed down the release rate of the fragrance and controlled the release rate of the fragrance in a thermo-sensitive manner. The liposomes adhered to the silk through electrostatic adsorption interaction. The positive charge on the fragrance-loaded liposomes neutralized much negative charge on silk and thereby increasing the adhesion efficiency. 相似文献