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971.
Mostafa Erfani Mina Tabatabaei Alireza Doroudi Mohammad Shafiei 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(2):491-500
Zoledronic acid is a bisphosphonates to treat bone problems. Rhenium-188-zoledronic acid could be used as a palliate agent in skeletal metastases. Radiolabeled product was prepared through optimized radiochemical procedures. The organs uptake especially bone uptake assessed in healthy animals mice. The radiochemical purity of the radiotracer was > 95% which was stable up to 24 h. Bone uptake (1.08?±?0.14% ID/g at 1 h) with retention of activity in bone up to 24 h (0.26?±?0.06% ID/g) was reached. This radiotracer can be used as a developing candidate for a palliative treatment of bone metastasis. 相似文献
972.
Phosphated tungstate as a new, reusable and efficient solid phosphoric acid catalyst was synthesized and used to promote the reaction of diaminoglyoxime with various aromatic aldehydes. The prepared phosphated tungstate was characterized using various techniques including X‐ray diffraction, scanning electron microscopy, energy‐dispersive X‐ray spectroscopy, Fourier transform infrared spectroscopy and thermal analysis. A wide variety of heterocyclic nitrones were obtained under mild reaction conditions and in high yields by using the prepared catalyst. 相似文献
973.
4,13-Didecyl-1,7,10,16-tetraoxa-4,13-diazacyclooctadecane (kryptofix22DD) has been explored as a neutral ionophore for preparing polyvinyl chloride (PVC)-based membrane sensor selective to lead(II). The optimized membrane incorporating kryptofix22DD as the active material, nitrobenzene as plasticizer and sodium tetraphenylborate as an anion excluder and membrane modifier in PVC (in the weight ratio of 5.0: 63.0: 2.0: 30.0, respectively) was directly coated on the surface of graphite rod. The sensor exhibits a Nernstian slope (29.4 mV/decade) in the concentration range of 1.0 × 10–5 to 1.0 × 10–1 M Pb2+. The detection limit of the sensor is 6.5 × 10–6 M. The proposed sensor has a fast response time (~10 s), a satisfactory reproducibility and relatively long lifetime. The electrode shows high selectivity toward Pb2+ ion in comparison to other common cations. The proposed sensor is suitable for use in aqueous solutions in a wide pH range of 2.0–10.0. It was used as an indicator electrode for the end point detection in the potentiometric titration of Pb2+ ion with ethylenediaminetetraacetic acid (EDTA) and sodium iodide (NaI) solutions. The proposed sensor was successfully applied for the recovery of Pb2+ ions spiked in real water samples. 相似文献
974.
975.
Alireza?KhataeeEmail author Mahsa?Haddad Irani-nezhad Javad?Hassanzadeh 《Mikrochimica acta》2018,185(3):190
It is reported that a mixture of WS2 nanosheets (WS2 NS) and silver nanoclusters (AgNCs) displays strongly enhanced peroxidase-mimicking activity. The catalytic effect of the mixture was studied by colorimetry, fluorometry, chemiluminescence (CL) and electrochemistry. The effect is interpreted in terms of a difference between the Fermi energy level of the two nanomaterials. This leads to the formation of charge separation regions which act as active sites for enzyme mimetic interaction with the substrates. The mixture of WS2 NS and AgNCs was exploited for the non-enzymatic determination of H2O2 and glucose. A stopped-flow method was applied as a sensitive CL detection system using the bicarbonate-H2O2 reaction. The mixture has a powerful peroxidase mimicking activity on the bicarbonate-H2O2 CL reaction, and this effect is much larger than that of any single constituent. In addition, the CL emission is improved several times by using the stopped-flow technique. Under optimum condition, H2O2 can be determined in the 2.5–1500 nM concentration range. Moreover, glucose levels in human serum can be quantified via glucose oxidase based oxidation which leads to the generation of H2O2. Using this CL assay, a linear relationship was obtained between the intensity of the CL emission and glucose concentration in the range of 0.03–20 μM, with a limit of detection (3S) of 13 nM. 相似文献
976.
Heman?Mirzapour Homayon?Ahmad?PanahiEmail authorView authors OrcID profile Elham?Moniri Alireza?Feizbakhsh 《Mikrochimica acta》2018,185(9):440
Magnetic nanoparticles (MNPs) modified with organic dendrimers are shown to be a viable sorbent of the microextraction of the drug rosuvastatin (RST; also known as Crestor). The MNPs were prepared from iron(II) chloride and iron(III) chloride and then coated with silicon dioxide. The coated MNPs produced by this method have diameters ranging from 10 to 60 nm according to scanning electron microscopy. The MNPs were further modified with organic dendrimers containing methyl methacrylate and ethylene diamine. The resulting MNPs were characterized by SEM, Fourier transform infra-red and thermal gravimetry analysis. Then, the efficacy of the modified MNPs with respect to the extraction of RST was studied. The adsorption of RST by MNPs can be best described by a Langmuir isotherm. Following elution with buffer, RST was quantified by HPLC. The method was applied to the determination of RST in (spiked) human blood plasma, urine, and in tablets. RST extraction efficiencies are 54.5% in plasma, 86.6% from the drug matrix, and 94.3% in urine. The highest adsorption capacity of the RST by the MNPs adsorbent was 61 mg?g?1. 相似文献
977.
Mir Mohammad Hassan Kahila Amin Mahdi Najy Mohammad Mir-Derikvand 《Natural product research》2018,32(15):1858-1862
Thymoquinone is the most important secondary metabolite in black Cumin, which has several pharmaceutical applications. In this study, effect of TiO2 and SiO2 nanoparticles as new elicitors, on expression of Geranyl diphosphate synthase gene (GPPS gene), as a key gene involved in thymoquione biosynthesis pathway was investigated in two Iranian accessions. Plants were treatment in the early flowering stage and after 24 h of 50 and 100 mg/L of each nanoparticle, separately. After RNA extraction, GPPS gene expression was analysed by qRT-PCR method. The results showed that the TiO2 and SiO2 nanoparticles, generally stimulates the GPPS expression. The TiO2 nanoparticles were more effective than SiO2 for the induction of GPPS expression. Also, 100 mg/L treatment of nanoparticles raised gene expression more than 50 mg/L concentration. It can be concluded these nanoparticles can be used as robust elicitors to enhance the production of Thymoquinone in black cumin through up-regulation of related metabolic pathway genes. 相似文献
978.
Baghban Alireza Pourfayaz Fathollah Ahmadi Mohammad Hossein Kasaeian Alibakhsh Pourkiaei Seyed Mohsen Lorenzini Giulio 《Journal of Thermal Analysis and Calorimetry》2018,131(2):1213-1220
Journal of Thermal Analysis and Calorimetry - The effect of Na2CO3 additive on the steam gasification characteristics of Sunjiahao (SJH) coal char was studied in the present paper. Na2CO3-catalyzed... 相似文献
979.
Research on Chemical Intermediates - A novel binuclear complex of niobium(V) containing two curcuminato, and two bridging chloro ligands, was synthesized and characterized by means of nuclear... 相似文献
980.
Ali Mohebbi Mahboob Nemati Mir Ali Farajzadeh Mohammad Reza Afshar Mogaddam Farzaneh Lotfipour 《Journal of separation science》2022,45(11):1894-1903
A temperature-induced counter-current homogenous liquid-liquid extraction procedure performed in a burette has been proposed for the isolation of aflatoxins B1, B2, G1, and G2 from various fruit chip samples. In this method, a homogenous solution of deionized water and cyclohexylamine is added to the solid sample and the resulted mixture is vortexed. In the following, the liquid phase is taken and passed through the burette filled with a mixture of calcium oxide (as a phase separation agent) and sand (to avoid clumping the calcium oxide). By doing so, the temperature of the solution is increased by hydration of calcium oxide and consequently, the homogenous state is broken and the aflatoxins are migrated into the resulted tiny droplets of cyclohexylamine. This phase is collected on the top of the solution owing to its low density with respect to an aqueous solution. Numerous parameters which can affect the efficiency of the suggested approach were evaluated and under the best situations, great repeatability, low limits of determination and quantification, and high extraction recoveries were acquired. In the end, the suggested approach was employed for the quantification of the selected aflatoxins in various fruit chips samples marketed in Tabriz City, Iran. 相似文献