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  • Author or Editor: A. R. Mohamed x
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Abstract  

Multielement neutron activation analysis has been applied to the determination of macro, micro and trace amounts of Al, Br, Ca, Cl, Co, Cr, Cs, Fe, K, La, Mg, Mn, Na, Rb, Sc and V in molasses of Kom Ombo, Edfu, Armant, Naga Hammady and Abu Korkass cane sugar factories. The threshold element concentrations are acceptable and below the safety. Differences in element concentrations may be related to different botanic textures and structures, different compositions of sugar cane plants, corrosion of containers or changes in soil as a result of geochemical differentiation. The method is sensitive down to 0.038 ppm of V. The relative errors due to counting statistics are in the range of 0.2–11%.

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Abstract  

Instrumental neutron activation analysis, INAA, was utilized for the determination of Al, Au, Br, Ca, Cl, Co, Cr, Cu, Fe, I, K, Mg, Mn, Na, Rb, Sc, V and W in 12 Tilapia Nilotica samples collected from the Aswan High Dam Lake following the destructive techniques.

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Determination of trace elements of egyptian crops by neutron activation analysis

II. Trace elements in umbelliferae and legumirosae families

Journal of Radioanalytical and Nuclear Chemistry
Authors: M. Sherif, R. Awadallah, and A. Mohamed

Abstract  

Neutron activation analysis, NAA, a high resolution Ge(Li) gamma ray spectrometer was used to determine the concentration of Al, As, Au, Br, Ca, Cd, Co, Cr, Cu, Fe, La, Mn, Mo, Sb, Se, W, and Zn in Cumin, coriander, carrots, and Daucus carrota (Umbelliferae Family), alfalfa, Kidney bean, Phaseolus sativus, Phaseolus vulgaris, bean, lenses, and fenugreek (Legumirosae Family). Multielement determination technique on destructive and nondestructive samples was followed. This method is simple, precise and sensitive to 17 trace elements.

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Abstract  

The concentration of 18 elements in different cane sugar products, i.e., cane sugar plants, crude and syrup juices, molasses, and the end products of the consumer sugar, were analyzed and processed. The samples were collected from five citics, i.e., Kom Ombo, Edfu, Armant, Deshna and Naga Hammady in Upper Egypt where the main Egyptian sugar industry factories are located. INAA was applied for the determination of Al, Ca, Cl, Co, Cr, Fe, Mg, Mn, Na and Sc, while Cu, Li, P, Sn, V and Zn were determined by ICP-AES and Pb and As were determined by AAS. These three analytical methods were applied to optimize the sensitivity and the accuracy of the measurements in order to provide a sound basis for the obtention of reliable clustering results.

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Summary

A simple, selective, precise, and stability-indicating thin-layer chromatographic method has been developed and validated for analysis of some angiotensin II receptor antagonists (AIIRAs), namely, Losartan potassium (Los-K), Irbesartan (Irb), and Candesartan cilexetil (Cand) in the bulk drug and in pharmaceutical formulations (tablets). The method was based on using TLC plates pre-coated with silica gel G 60 on aluminum sheets as stationary phase and the development system was performed using chloroform:methanol (9:1) giving well separated and compact spots for all the studied drugs (R F values 0.41–0.53). The separated spots were characterized by viewing under the UV lamp, then visualized as orange spots by spraying with Dragendorff's reagent and measured by densitometry. Under the optimum chromatographic conditions, linear relationships were obtained between response and concentrations of each studied drug with high correlation coefficients (0.9985–0.9994). Good accuracy and precision were successfully obtained for the analysis of tablets containing each drug alone or combined with diuretic drug hydrochlorothiazide (HCTZ). No interferences could be observed from the co-formulated HCTZ, commonly encountered excipients present in tablets as well as the degradation products. The results were compared successfully with reported methods and can be used as a stability-indicating assay.

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Abstract  

Multielemental instrumental neutron activation (INAA), inductively coupled plasmaatomic emission spectrometric (ICP-AES) and atomic absorption spectrophotometric (AAS) analyses are utilized for the determination of Ag, Al, As, Au, Ba, Be, Br, Ca, Cd, Ce, Cl, Co, Cr, Cu, Eu, Fe, Ga, Hf, K, La, Li, Lu, Mg, Mn, Na, Nb, Ni, P. Pb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Th, Ti, U, V, W and Zn in sugar cane plant, raw juice, juice in different stages, syrup, deposits, molasses, A, B and C sugar, refinery 1 and 2 sugar, and in soil samples picked up from the immediate vicinity of the cane plant roots at surface, 30 and 60 cm depth.

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Abstract  

Major, minor, trace and ultratrace concentrations of Ag, Al, As, Au, Ba, Be, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Eu, Fe, Ga, Hf, K, La, Li, Lu, Mg, Mn, Na, Nb, Ni, P, Pb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Th, Ti, U, V, W and Zn in crude juice, principal juice, sirup juice (produced during the successive stages of sugar industry), sugar cane plant, molasses, deposits (produced as a result of the addition of Ca(OH)2 and superphosphate and passage of SO2 through juice), A-and B-sugar and soil samples have been determined by destructive and nondestructive instrumental neutron activation (INAA), atomic absorption spectrophotometric (AAS) and inductively coupled plasma-atomic emission spectrometric (ICP-AES) analyses. The results obtained by the methods applied are in excellent agreement. Concentrations of the elements are different. Variations in element concentrations in cance plants and in crude juice may be attributed to composition changes or different botanical structures; in mixed juice, sirup, molasse and deposits they may be due to chemical treatments or corrosion effects on containers, whereas in soil samples to geochemical and biogeochemical fractionation as a result of adsorption and uptake of trace elements by plants from surrounding soil solutions.

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A new spectrodensitometric method was developed for the simultaneous determination of a quaternary mixture of antihyperlipidemics containing niacin, atorvastatin, and bezafibrate with either ezetimibe or simvastatin. Densitometric analysis was carried out using high-performance thin-layer chromatographic (HPTLC) silica gel 60G F254 plates as the stationary phase. The plates were developed with benzene—ACN—n-butanol (7:2:1, v/v) + 1.50%, v/v, glacial HOAC in absorbance mode at 242 nm. The retention factors of niacin, atorvastatin, bezafibrate, ezetimibe, and simvastatin were 0.17, 0.38, 0.51, 0.65, and 0.66, respectively. The method was validated according to the United States Pharmacopeia and National Formulary (USP 31—NF 26) and the International Conference on Harmonization (ICH) guidelines. Linearity ranges of all studied drugs were found to be in the range of 15–650 ng band−1 with correlation coefficient values of 0.9975 or more. Limits of detection and quantitation were 5–50 and 15–150 ng band−1, respectively. Upon applying polynomial regression to the same concentration ranges of standard solutions of all investigated drugs as well as spiked bezafibrate samples to rabbit plasma, correlation coefficient values had greatly improved. The proposed method was successfully applied for the simultaneous determination of the studied antihyperlipidemic drugs in plasma and in their pharmaceutical formulations. The developed method was utilized to study the pharmacokinetic behavior of bezafibrate and its drug—drug interaction with atorvastatin in rabbit males. This study has proven the increased myotoxicity risk upon coadministration of atorvastatin with bezafibrate.

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