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81.
A novel and effective electrochemical sensor for the determination of morphine (MO) in 0.04 mol L(-1) universal buffer solution (pH 7.4) is introduced using gold nanoparticles electrodeposited on a Nafion modified carbon paste electrode. The effect of various experimental parameters including pH, scan rate and accumulation time on the voltammetric response of MO was investigated. At the optimum conditions, the concentration of MO was determined using differential pulse voltammetry (DPV) in a linear range of 2.0 × 10(-7) to 2.6 × 10(-4) mol L(-1) with a correlation coefficient of 0.999, and a detection limit of 13.3 × 10(-10) mol L(-1), respectively. The effect of common interferences on the current response of morphine namely ascorbic acid (AA) and uric acid (UA) is studied. The modified electrode can be used for the determination of MO spiked into urine samples, and excellent recovery results were obtained. 相似文献
82.
JPC – Journal of Planar Chromatography – Modern TLC - This research article describes a simple and sensitive thin-layer chromatographic (TLC)-densitometric method for simultaneous... 相似文献
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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
85.
Maha M. Abdelrahman Amal B. Ahmed Mahmoud A. Omar Sayed M. Derayea Nada S. Abdelwahab 《Journal of separation science》2020,43(15):2981-2988
Citicoline and piracetam were subjected separately to different stress conditions as recommended by the international conference on harmonization. In addition, new stability indicating thin layer chromatographic and ultra high performance liquid chromatographic methods have been developed and validated for simultaneous determination of citicoline and piracetam in presence of their degradation products. Separation on the proposed thin layer chromatographic method was carried out using a developing system containing methanol:chloroform:ammonium chloride buffer (9:1:2, v/v/v) on silica gel plates at 230 nm. On the other hand, the mobile phase in the ultra high performance liquid chromatographic method was composed of water (containing 0.1% triethylamine):ethanol (92:8, v/v). The flow rate was 1 mL/min and ultraviolet detection was at 230 nm. Moreover, results of the developed methods were statistically compared to those obtained by the reported high‐performance liquid chromatography method and no significant difference between them was found. The greenness profile of ultra high performance liquid chromatographic method was assessed and compared with those of the previously published high‐performance liquid chromatography methods, it was noticed that the proposed ultra high performance liquid chromatographic method more environmentally friendly and greener than other methods. 相似文献
86.
The X-ray structure of (Ph3P)2Ag(SOC2SO)Ag(PPh3)2 shows this complex as the second authentic example containing a bridging trans-1,2-dithiooxalate ligand. The compound crystallizes in the monoclinic space group P21/c with a=13.159(2), b=11.895(2), c=20.939(5)Å, β= 101.35(2)° and Z = 2. The structure was solved by Patterson and Fourier methods for 5649 diffractometer data and refined to a final R value of 0.066 for 03545 observed reflections. The dimensions of the dithiooxalate bridge are compared with those of the corresponding trans-dithiooxalate in (Ph4As)4 (O2C2S2)2In(SOC2SO)In(S2C2O2)2]. Differences between structures containing bridging trans-dithiooxalate or bridging cis-dithiooxalate, respectively, are discussed. 相似文献
87.
Perišić-Janjić Nada U. Djaković-Sekulić Tatjana Lj. Jevrić Lidija R. Jovanović Bratislav Ž. 《平面色谱法杂志一现代薄层色谱法》2005,18(3):212-216
JPC – Journal of Planar Chromatography – Modern TLC - Quantitative structure-retention relationships (QSRR) have been used to study the chromatographic behavior of some s-triazines.... 相似文献
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Sherif Abdelmoez Rehab A. Abd El Azeem Ahmed A. Nada Tawfik A. Khattab 《无机化学与普通化学杂志》2016,642(3):219-221
Nowadays, encapsulated dyes in a polymeric matrix have opened up new perspectives in many applications such as filtration of subatomic particles, composite reinforcement, multifunctional membranes, tissue engineering scaffolds, wound dressing, coatings, medical purposes as well as sensors. In the presented work, we report on electrospinning neat peryelene dianhydride based thermoplastic elastomers. Perylene‐3, 4,9, 10‐tetracarboxylic dianhydride (PDA) is encapsulated into cellulose acetate (CA) electrospun fibers, which was prepared from 12 % cellulose acetate solution, at 20 kV with a distance of 10 cm. The flow rate was 0.2 ml · h–1. These water repellent nanofibrous coatings are anticipated to serve as hydrophobic coatings. Scanning electron microscope is used to study the properties of the electrospun PDA‐CA nanofibers. 相似文献