scholarly journals Spectrophotometric methods for osmium determination using organic reagents: application to intermetallides

2009 ◽  
Vol 2 (1/2) ◽  
pp. 89-93 ◽  
Author(s):  
Mariana V. RYDCHUK ◽  
◽  
Galyna M. MYKHALYNA ◽  
Oksana S. BONISHKO ◽  
Olga P. DOBRYANSKA ◽  
...  
2006 ◽  
Vol 75 (4) ◽  
pp. 341-349 ◽  
Author(s):  
Sergey B Savvin ◽  
S N Shtykov ◽  
Alla V Mikhailova

2010 ◽  
Vol 4 (2) ◽  
pp. 115-124
Author(s):  
Mariana Rydchuk ◽  
◽  
Teodoziya Vrublevska ◽  
Mariya Boyko ◽  
Olha Korkuna ◽  
...  

The selectivity of the spectrophotometric methods for determination of microgram quantities of osmium (IV) with acidic monoazo dyes Tropaeolin O (TpO) and Tropaeolin OOO-I (TpOOOI) in the presence of concomitant metals, particularly platinum group, heavy and rare earths (RE) has been studied. The tolerance ratios of interfering elements have been established. The selectivity of the interaction of TpOOOI with osmium (IV) relatively to platinum group elements (PGEs) is much better than TpO. It has been established that the influence of interfering ions can be easily eliminated by means of masking agents viz. EDTA, tartrate, citrate, pyrophosphate and fluoride, and thereby the selectivity of the methods of osmium determination with TpO and TpOOOI has been sufficiently improved. The methods have been approved during the analyses of various model solutions containing ruthenium, platinum, palladium, rhodium and iridium and the masking reagents. Also osmium content has been determined in the intermetallic alloy Nd20Os15Sі65. The standard deviations did not exceed typical values for spectrophotometric methods (RSDs < 5 %). Thus the elaborated methods with various masking agents may be used for direct determination of osmium in complex samples without any preliminary separation of osmium in the form of OsO4 as well as without the extraction of matrices elements.


ChemInform ◽  
2006 ◽  
Vol 37 (37) ◽  
Author(s):  
S. B. Savvin ◽  
S. N. Shtykov ◽  
A. V. Mikhailova

1960 ◽  
Vol XXXIII (III) ◽  
pp. 417-427 ◽  
Author(s):  
John Kristoffersen

ABSTRACT By means of chromatographic and spectrophotometric methods progesterone and a substance closely similar to 20β-hydroxy-pregn-4-ene-3-one has been detected in luteal tissue from non-pregnant and pregnant cows. In 21 animals quantitative measurements based on a method giving an average net recovery of 56 per cent showed that in pregnancy the average progesterone content in the corpus luteum reached a maximum in the third to fifth month, with low values before and after this period. For 6 nonpregnant cows, the average value was 20.2 μg/g tissue, which is considerably higher than previous values reported in the literature. The relation between these findings and the bovine dependence on a functional corpus luteum in pregnancy is discussed, and it is pointed out that more information about the metabolism of progesterone in cattle is highly desirable.


Author(s):  
Abbas Shebeeb Al-kadumi ◽  
Sahar Rihan Fadhel ◽  
Mohammed Abdullah Ahmed ◽  
Luma Amer Musa

We proposed two simple, rapid, and convenient spectrophotometric methods are described for the determination of Amoxicillin in bulk and its pharmaceutical preparations. They are based on the measurement of the flame atomic emission of potassium ion (in first method) and colorimetric determination of the green colored solution for manganite ion at 610 nm formed after reaction of Amoxicillin with potassium permanganate as oxidant agent (in the second method) in basic medium. The working conditions of the methods were investigated and optimized. Beer's law plot showed a good correlation in the concentration range of 5-45 μg/ml. The detection limits and relative standared deviations were (2.573, 2.814 μg/ml) (2.137, 2.498) for the flame emission photometric method and (1.844, 2.016 μg/ml) (1.645,1.932) for colorimetric methods for capsules and suspensions respectively. The methods were successfully applied to the determination of Amoxicillin in capsules and suspensions, and the obtained results were in good agreement with the label claim. No interference was observed from the commonly encountered additives and expectancies.


2020 ◽  
Vol 16 ◽  
Author(s):  
Mamdouh R. Rezk ◽  
Mina Wadie ◽  
Soheir A. Weshahy ◽  
Mahmoud A. Tantawy

Background: Alfuzosin is recently co-formulated with solifenacin for relieving two coincident urological diseases, namely; benign prostate hyperplasia and overactive bladder Objective: Herein, green, simple and rapid spectrophotometric methods were firstly developed for simultaneous determination of the two cited drugs in their co-formulated pharmaceutical capsule Methods: Alfuzosin, which is the major component in the dosage form, was directly assayed at its extended wavelength at 330.0 nm. The challenging spectrum of the minor component, solifenacin, was resolved by five spectrophotometric methods, namely; dual wavelength (DW) at 210.0 & 230.0 nm, first derivative (1D) at 222.0 nm, ratio difference (RD) at 217.0 - 271.0 nm , derivative ratio (1DD) at 223.0 and mean centering of ratio spectra (MC) at 217.0 nm Results: The Proposed methods were successfully validated as per ICH guidelines. Alfuzosin showed linearity over the range of 4.0 - 70.0 μg/mL, while that of solifenacin were 4.0 - 50.0 μg/mL for DW, 2.0 - 70.0 μg/mL for 1D and RD methods, 1.0 - 70.0 μg/mL for 1DD and 4.0 - 70.0 μg/mL for MC method. Statistical comparison with their official ones showed no noticeable differences. The methods showed good applicability for assaying drugs in their newly combination. Besides eco-scale, the greenness profile of the methods was assessed and compared with the reported spectrophotometric one via the newest metric tool; green analytical procedure index (GAPI). Conclusions: The proposed methods are superior in not only being smart, accurate, selective, robust and time-saving, but also in using distilled water as an eco-friendly and cheap solvent


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