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111.
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113.
Bizhan Malaekeh-Nikouei Toka Banaee Javad Aghamohammadian Navid Mosallaei Seyed Ahmad Mohajeri 《Chromatographia》2011,73(7-8):817-821
An isocratic reversed-phase HPLC method with ultraviolet detection at 205 nm has been developed for analysis of cyclosporine A (CyA) in rabbit ocular samples. Neither internal standard nor extraction was needed for sample preparation. Acetonitrile (ACN; 1 mL) was added to 250 μL aqueous and vitreous samples to precipitate proteins. The supernatant was dried and the residue was reconstituted in mobile phase and injected for HPLC analysis. Chromatography was performed on an octadecyl silane-A (ODSA) C18 (4.6 × 250 mm, 5 μm) column. The column temperature was fixed at 70 °C and the mobile phase was ACN 65%, methanol 20% and water 15% at a flow rate of 1.5 mL min?1. The calibration curve for CyA in rabbit ocular samples was linear over the concentration range 0.2 and 10 μg mL?1 with a correlation coefficient of 0.9992. Intra-day and inter-day precision were 4.61–7.83% and 5.27–10.70%, respectively. Intra-day and inter-day accuracy were 89.2–108% and 83.4–111%, respectively. The limits of detection (LOD) and quantification (LOQ) were 5.7 and 38 ng mL?1, respectively. The method was successfully used for analysis of CyA in real aqueous and vitreous humor samples from New Zealand albino rabbits. The method is therefore suitable for analysis of CyA in ocular samples. 相似文献
114.
The mechanism of catalytic reduction of peroxydisulfate on the palladized aluminum electrode modified by Prussian blue (PB/Pd‐Al) was studied. The charge transfer‐rate limiting step as well as overall reduction reaction of S2O82? is found to be a one‐electron and two‐electron abstraction respectively. The modified electrode is exploited for the hydrodynamic amperometry of peroxydisulfate. It is found that the calibration graph is linear in the S2O82?concentration range 5×10?6–1.5×10?3 mol L?1. The detection limit of the method was 2.4×10?6 mol L?1 S2O82. The method was successfully used for the determination of S2O82? in decolorizing powders 相似文献
115.
For classes of periodic functions defined by constraints imposed on the L
1-norm of the result of action of differential operators with constant coefficients and real spectrum on these functions, we
determine the exact values of the best L
1-approximations by generalized splines from the classes considered.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 50, No. 11, pp. 1443–1451, November, 1998. 相似文献
116.
In this work we investigate the single- and the double-spin asymmetries at the collisions of polarized protons pp → (γ
*, Z
0, Z′) + X within the scope of QCD, the electroweak interaction and superstring E
6 theory. The helicity amplitude method is used. Analytical expressions for the single- and the double-spin asymmetries are
obtained and their dependence on the transverse momentum of the lepton pair is investigated at the three different values
of invariant masses of the lepton pair. The pure contribution coming from the superstring Z′ boson on the single- and double- spin asymmetries has been extracted. The results obtained allow investigation of the spin
structure of the proton. 相似文献
117.
Solmaz Ghaffari Nasim Sadri Alamdari Zahra Jafari Azar Ali Reza Dabir Siaghi Farzad Kobarfard Sanaz Ghaffari 《Journal of Dispersion Science and Technology》2013,34(9):1332-1335
Preparation of sustained release dosage forms is one of the main objectives in drug formulation. Theophylline that has a narrow therapeutic index, making it a good choice to prepare a sustained release dosage form. Theophylline sustained release microcapsules were prepared by applying the coacervation method. The effect of the type and ratio of polymers, as well as the type of washing solvents, was studied on particle size, drug loading efficiency, and in vitro drug release profile. Results showed that Eudragit RS and RL could be more suitable polymers for preparation of sustained release microcapsules of theophylline when used in ratio of 1:1 and when the washing solvent was hexane. 相似文献
118.
MOHAJERI Seyed Amin SAJADI TABASSI Sayyed Abolghasem HASSANPOUR MOGHADAM Maryam MOHAJERI Seyed Ahmad 《中国科学:化学(英文版)》2014,57(6):857-865
The aim of this work was to synthesize a pantoprazole-imprinted polymer(MIPs)and study its binding and release properties in an aqueous media.Methacrylic acid(MAA),methacrylamide(MAAM),hydroxyethyl methacrylate(HEMA),and 4-vinyl pyridine(4VP)were tested as functional monomers.Different solvents were also applied as polymerization media under heat or UV radiation.The optimized MIP was prepared in chloroform as a solvent,4-vinyl pyridine as a functional monomer,and ethylene glycole dimethacrylate(EGDMA)as a crosslinker monomer under UV irradiation.Binding and release properties of MIP were studied in comparison with a non-imprinted polymer(NIP)in aqueous media,at different pH values.The protective effect of polymer for drugs against acidic conditions was evaluated at pH 2.Results indicated that the MIP had superior binding properties compared to NIP for pantoprazole.The percentage of drug released from MIP was significantly less than from NIP at all pH values,which was attributed to the presence of imprinted cavities in the MIP matrix.MIP also had a stronger protective effect for pantoprazole in acidic media,in comparison with NIP. 相似文献
119.
Multiwall Carbon Nanotube‐Ionic Liquid Modified Paste Electrode as an Efficient Sensor for the Determination of Diazepam and Oxazepam in Real Samples
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M. A. Zare M. Saber Tehrani S. Waqif Husain P. Aberoomand Azar 《Electroanalysis》2014,26(12):2599-2606
A carbon‐based electrode using multiwall carbon nanotube as a modifier and room temperature ionic liquid as a binder has been applied for the determination of diazepam (DZP) and oxazepam (OZP) in real samples including serum, urine and tablets. Square wave voltammetry as an appropriate electrochemical technique was applied to achieve improved limits of detection and higher sensitivities. The electrochemical studies were investigated under various experimental conditions such as pH, buffer concentration, ionic strength, deposition potential, deposition time and scan rate to achieve higher sensitivities. Linear concentration ranges for DZP and OZP were 0.02–0.76 mg L?1 and 0.05–1.90 mg L?1 with the detection limits of 4.1 µg L?1 and 5.8 µg L?1, respectively. The proposed method was successfully applied for the analysis of commercially available tablets as well as serum and urine samples and satisfactory results were obtained. 相似文献