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91.
JPC – Journal of Planar Chromatography – Modern TLC - A sensitive high-performance thin-layer chromatographic (HPTLC) method was developed for the estimation of metformin in human... 相似文献
92.
Eman A. Abdelwaly Abeer A. Mohamed Amira M. El-Kosasy Miriam F. Ayad 《Biomedical chromatography : BMC》2022,36(3):e5292
Combining short-acting and long-acting insulin analogs was a real challenge that was overcome by NovoNordisk through the co-formulation of insulin aspart and insulin degludec in single-dosage form. The proposed study provides a simple, short, and reliable HPLC method with diode array detection that is developed and validated for the simultaneous determination of insulin aspart and insulin degludec in human plasma. The proposed method achieved good separation between the two analytes utilizing a C8 column at 35°C in a very short run time (6 min), with a simple, low-cost, and reliable extraction method through precipitation of plasma protein. Gradient elution was applied using a mobile phase consisting of 0.1 M sodium sulfate (pH 3.4) and acetonitrile. The method was validated according to EMA Guideline on Bioanalytical Validation. The proposed method had a linear range from 3.0 to 300 μg/mL for insulin aspart and from 3.5 to 300 μg/mL for insulin degludec. The intra- and inter-day precision of insulin aspart were 0.36–3.33% and 1.59–8.84%, respectively, and accuracy was between 10.06 and 3.09% The intra- and inter-day precision of insulin degludec were 0.29–1.93% and 0.89–5.14%, respectively, and accuracy was between −5.29 and 3.91%. 相似文献
93.
Mohamad M. Ahmad Eman Al-Libidi Abdullah Al-Jaafari Syed Ghazanfar Koji Yamada 《Applied Physics A: Materials Science & Processing》2014,116(3):1299-1306
CaCu3Ti4O12 powder has been synthesized by mechanochemical milling (C-m) and solid-state reaction (C-ssr) techniques. C-m powder has a grain size of ~24 nm as determined from X-ray diffraction and FE-SEM measurements. The grain size of C-m ceramics has increased to 20 μm compared to a size of 3 μm for C-ssr ceramics after sintering at 1,050 °C for 10 h. Giant dielectric constant was observed in both ceramics with that of C-m larger than that of C-ssr. Impedance results show that the grain conductivity of C-m is more than two orders of magnitude lower than that of C-ssr, whereas its grain boundary conductivity is larger than that of C-ssr. These results are supported by the EDX results that show Cu-enriched grain boundaries in C-m ceramics. 相似文献
94.
This paper describes the development of screen-printed (SPE) and carbon paste (CPE) sensors for the rapid and sensitive quantification of naphazoline hydrochloride (NPZ) in pharmaceutical formulations. This work compares the electroactivity of conventional carbon paste and screen-printed carbon paste electrodes towards potentiometric titration of NPZ. The repeatability and accuracy of measurements performed in the analysis of these pharmaceutical matrices using new screen printed sensors were evaluated. The influence of the electrode composition, conditioning time of the electrode and pH of the test solution, on the electrode performance were investigated. The drug electrode showed Nernstain responses in the concentration range from 1 × 10(-6) to 1 × 10(-2) mol L(-1) with slopes of 57.5 ± 1.3 and 55.9 ± 1.6 mV per decade for SPE and CPE, respectively, and was found to be very precise and usable within the pH range 3-8. These sensors exhibited a fast response time (about 3 s for both SPE and CPE, respectively), a low detection limit (3.5 × 10(-6) and 1.5 × 10(-6) M for SPE and CPE, respectively), a long lifetime (3 and 2 months for SPE and CPE, respectively) and good stability. The selectivity of the electrode toward a large number of inorganic cations, sugars and amino acids was tested. It was applied to potentiometric determination of NPZ in pure state and pharmaceutical preparation under batch conditions. The percentage recovery values for the assay of NPZ in tablets (relative standard deviations ≤0.3% for n = 4) were compared well with those obtained by the official method. 相似文献
95.
Eman A. El Rady 《合成通讯》2013,43(1):37-49
4‐Amino‐5‐arylmethylidene‐3‐phenyl‐pyridazin‐6‐ones 7 have been synthesized and reacted with selected nucleophile reagents such as phenyl hydrazine, semicarbazide, semithiocarbazide, cyanoacetohydrazide, 2‐aminothiophenol, and 2‐phenylenediamine in ethanol triethyl‐amine solution. An unexpected 1‐phenyl‐3‐arylaziridene 10, 3‐aryl‐5‐oxo(thio)‐1,2,4‐triazole 21, 4‐amino‐3‐aryl‐6‐hydroxy‐pridazine 27, 2‐arylbenzothiazole 30a–c, and 2‐arylbenzimidazole 30d–f have been obtained, respectively. Also, 2‐aminothiophenol and 2‐phenylenediamine were reacted with N‐phenylmethylidene‐2‐cyanoacetohydrazide 2, affording the new 1,4‐benzodiazepine derivatives 35. 相似文献
96.
Fawi M. Abd El Latif Eman A. Ei Rady Mohamed A. Khalil 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2497-2505
2-Cyano-2-nitrosomethylbenzthiazole reacts with some active methylene and nucleophile derivatives to yield new fused and isolated polyfunctional pyrazine, -[1,2,4]triazine, -[1,4,5]benzoxadiazepin, -[1,4,5]benzothiadiazepine, [1,4,5]benzotriazepine, -triazole and -triazolo[3,2-c]triazine derivatives in one-pot reaction. The structures were based on IR, MS, and 1 H NMR spectra and elemental data. 相似文献
97.
Kamal M. Dawood Eman A. Ragab Ahmad M. Farag 《Phosphorus, sulfur, and silicon and the related elements》2013,188(8):1796-1802
Treatment of 3-cyanoacetylpyrazole derivative 1 with phenyl isothiocyanate in potassium hydroxide at room temperature followed by α-haloketones 4a–d and hydrazonoyl halides 10a–e gave the corresponding pyrazolylthiophene 6a–d and pyrazolyl-1,3,4-thiadiazole 12a–e derivatives, respectively. 相似文献
98.
Utility of 6‐Amino‐2‐thiouracils as a Core of Biologically Potent Polynitrogen–Sulfur Fused Heterocycles
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Samira T. Rabie Reham A. Abdel‐Monem Nadia R. Mohamed Ahmed I. Hashem Afaf A. Nada 《Journal of heterocyclic chemistry》2014,51(Z1):E189-E196
One pot three‐component reaction was assisted to form some new pyridopyrimidine derivatives to be investigated as antimicrobial and antitumor agents. The newly synthesized compounds showed high significant antimicrobial activity against the applied strains of both Gram‐positive and Gram‐negative bacteria and fungi. The cytotoxic activity of some compounds was evaluated as inhibitor of growth in both human liver carcinoma and breast cell lines. The results showed that some compounds exhibited very high cytotoxicity against human liver cell line and breast cancer cells. 相似文献
99.
Haller E Rabie M Mark MJ Danzl JG Hart R Lauber K Pupillo G Nägerl HC 《Physical review letters》2011,107(23):230404
We investigate local three-body correlations for bosonic particles in three dimensions and one dimension as a function of the interaction strength. The three-body correlation function g(3) is determined by measuring the three-body recombination rate in an ultracold gas of Cs atoms. In three dimensions, we measure the dependence of g(3) on the gas parameter in a BEC, finding good agreement with the theoretical prediction accounting for beyond-mean-field effects. In one dimension, we observe a reduction of g(3) by several orders of magnitude upon increasing interactions from the weakly interacting BEC to the strongly interacting Tonks-Girardeau regime, in good agreement with predictions from the Lieb-Liniger model for all strengths of interaction. 相似文献
100.
Estevez L Kelarakis A Gong Q Da'as EH Giannelis EP 《Journal of the American Chemical Society》2011,133(16):6122-6125
We report the synthesis of multifunctional hybrids in both films and bulk form, combining electrical and ionic conductivity with porosity and catalytic activity. The hybrids are synthesized by a two-step process: (a) ice templation of an aqueous suspension comprised of Nafion, graphite oxide, and chloroplatinic acid to form a microcellular porous network and (b) mild reduction in hydrazine or monosodium citrate which leads to graphene-supported Pt nanoparticles on a Nafion scaffold. 相似文献