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271.
A new method based on the combination of magnetic solid phase extraction (MSPE) and spectrofluorimetric determination was developed for isolation and preconcentration of fluoxetine form aquatic and biological samples using sodium dodecyl sulfate (SDS) coated Fe3O4 nanoparticles (NPs) as a sorbent. The unique properties of Fe3O4 NPs including high surface area and strong magnetism were utilized effectively in the MSPE process. Effect of different parameters influencing the extraction efficiency of fluoxetine including the amount of Fe3O4 and SDS, pH value, sample volume, extraction time, desorption solvent and time were optimized. Under optimized condition, the method was successfully applied to the extraction of fluoxetine from water and urine samples and absolute recovery amount of 85%, detection limit of 20 μg L−1 and a relative standard deviation (RSD) of 1.4% were obtained. The method linear response was over a range of 50–1000 μg L−1 with R2 = 0.9968. The relative recovery in different aquatic and urine matrices were investigated and values of 80% to 104% were obtained. The whole procedure showed to be conveniently fast, efficient and economical for extraction of fluoxetine from environmental and biological samples. 相似文献
272.
Motabar O Goldin E Leister W Liu K Southall N Huang W Marugan JJ Sidransky E Zheng W 《Analytical and bioanalytical chemistry》2012,402(2):731-739
Glucocerebrosidase is a lysosomal enzyme that catalyzes the hydrolysis of glucosylceramide to form ceramide and glucose. A
deficiency of lysosomal glucocerebrosidase due to genetic mutations results in Gaucher disease, in which glucosylceramide
accumulates in the lysosomes of certain cell types. Although enzyme replacement therapy is currently available for the treatment
of type 1 Gaucher disease, the neuronopathic forms of Gaucher disease are still not treatable. Small molecule drugs that can
penetrate the blood-brain barrier, such as pharmacological chaperones and enzyme activators, are new therapeutic approaches
for Gaucher disease. Enzyme assays for glucocerebrosidase are used to screen compound libraries to identify new lead compounds
for drug development for the treatment of Gaucher disease. But the current assays use artificial substrates that are not physiologically
relevant. We developed a glucocerebrosidase assay using the natural substrate glucosylceramide coupled to an Amplex-red enzyme
reporting system. This assay is in a homogenous assay format and has been miniaturized in a 1,536-well plate format for high
throughput screening. The assay sensitivity and robustness is similar to those seen with other glucocerebrosidase fluorescence
assays. Therefore, this new glucocerebrosidase assay is an alternative approach for high throughput screening. 相似文献
273.
274.
Clinton Ramstadius Omid Hekmat Lars Eriksson Henrik Stålbrand Ian Cumpstey 《Tetrahedron: Asymmetry》2009,20(6-8):795-807
A partially protected C-5C-5a unsaturated carbasugar with α-lyxo configuration is synthesised in five steps and 26% overall yield from a known mannose-derived hemiacetal, using ring-closing metathesis as a key step. This carbasugar is converted into valienamine derivatives with β-lyxo (i.e., corresponding to β-manno at C-1–C-4), α-lyxo (i.e., corresponding to α-manno at C-1–C-4) and β-2-acetamido-2-deoxy-xylo (i.e., corresponding to β-GlcNAc at C-1–C-4) configurations. This is the first report of the synthesis of the β-lyxo compound, 1,2-bis-epi-valienamine, which was found to inhibit Cellulomonas fimi β-mannosidase (CfMan2A) with Ki 140 μM. We report the crystal structures of three protected C-5C-5a unsaturated carbasugars with lyxo configuration. 相似文献
275.
Akbar H. Borzabadi Omid S. Fard 《Journal of Computational and Applied Mathematics》2009,232(2):449-454
In this paper an iterative approach for obtaining approximate solutions for a class of nonlinear Fredholm integral equations of the second kind is proposed. The approach contains two steps: at the first one, we define a discretized form of the integral equation and prove that by considering some conditions on the kernel of the integral equation, solution of the discretized form converges to the exact solution of the problem. Following that, in the next step, solution of the discretized form is approximated by an iterative approach. We finally on some examples show the efficiency of the proposed approach. 相似文献
276.
Motallebi Hasankola Seyed Sadegh Shafaghat Rouzbeh Jahanian Omid Talesh Amiri Saleh Shooghi Mahdi 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2465-2474
Journal of Thermal Analysis and Calorimetry - In this paper, the effects of inlet valve closing temperature (TIVC) and exhaust gas recirculation (EGR) on the emissions and the performance of a... 相似文献
277.
Le Ba Thong Mahian Omid Wongwises Somchai Szilágyi Imre Miklós 《Journal of Thermal Analysis and Calorimetry》2020,142(3):1145-1172
Journal of Thermal Analysis and Calorimetry - Graphene has attracted much attention from the science world because of its mechanical, thermal, and physical properties. Graphene nanofluid is well... 相似文献
278.
Ghaedi Ashkan Shafaghat Rouzbeh Jahanian Omid Motallebi Hasankola Seyed Sadegh 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2487-2487
Journal of Thermal Analysis and Calorimetry - Unfortunately, in the original publication of the article the second author’s first name was inadvertently misspelled 相似文献
279.
Motallebi Hasankola Seyed Sadegh Shafaghat Rouzbeh Jahanian Omid Nikzadfar Kamyar 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2517-2517
Journal of Thermal Analysis and Calorimetry - Unfortunately, in the original publication of the article the second author’s first name was inadvertently misspelled. The corrected author name... 相似文献
280.