scholarly journals New oxidative electrophilic coupling reactions and their application to spectrophotometric determination of iron(III) in environmental waters, soils and industrial effluent samples

2012 ◽  
Vol 10 (1) ◽  
pp. 27-36
Author(s):  
Okab Al ◽  
Abdul Galil
Keyword(s):  
Industrial Effluent ◽  
Environmental Water ◽  
Coupling Reactions ◽  
Coupling Reagents ◽  
Reaction Conditions ◽  
Red Color ◽  
Water And Soil Samples ◽  
Optimum Reaction ◽  
Trace Concentrations

New oxidative electrophilic coupling reagents, 2-amino-2?,5-dichlorobenzophenone (MCB) or 2-amino-5-chloro-2'-fluorobenzophenone (MFB) are exploited for the determination of trace concentrations of iron(III) in environmental water and soil samples. The methods were based on oxidation of the electrophilic coupling reagents, 2-amino- 2?,5-dichlorobenzophenone (MCB) or 2-amino-5-chloro-2'-fluorobenzophenone (MFB) by iron(III) and coupling with phenoxazine (PNZ) in acidic medium to yield red color derivative having an absorbance maximum at 520 nm, which is stable up to 12 h. Beer?s law are obeyed for iron in the concentration ranges 0.31-1.2121 ?gmL-1 and 0.42-1.41 ?gmL-1, respectively. The optimum reaction conditions and other important analytical parameters were established. Interference due to various non-target ions was also investigated. The developed methods were applied to the analysis of iron(III) in various matrices. The performance of developed methods were evaluated in terms of Student?s t-test and variance ratio F-test that indicate the significance of developed methods over reported method.

Determination of nitrites by the formation of bisazo dye

2007 ◽  
Vol 61 (6) ◽  
Author(s):  
B. Dayananda ◽  
H. Revanasiddappa
Keyword(s):  
Sample Volume ◽  
Molar Absorptivity ◽  
Reaction Conditions ◽  
Final Sample ◽  
Water And Soil Samples ◽  
Bromide Ion ◽  
Optimum Reaction ◽  
Acidic Conditions ◽  
Diazonium Ion

AbstractA facile, sensitive and rapid spectrophotometric method for the determination of nitrite is presented. The method involves the reaction of nitrite with 4-aminoazobenzene under acidic conditions in the presence of a bromide ion allowing to complete the diazotization reaction almost instantaneously. The formed diazonium ion is then coupled with acetyl acetone to give bisazo dye in an aqueous alkaline medium having maximum absorption at 500 nm. The molar absorptivity and Sandell’s sensitivity of the method were found to be 4.2 × 104 dm3 mol−1 cm−1 and 1.1 ng cm−2, respectively. The system obeys the Beer’s law within the concentration range of 0.1–9 µg of nitrite in the final sample volume of 10 cm3. Optimum reaction conditions were evaluated and the influence of ionic interference on the determination of nitrite has been studied. The developed method has been applied in the determination of nitrite in water and soil samples, and the results were statistically evaluated.

scholarly journals New Diazo Coupling Reactions for Visible Spectrophotometric Determination of Alfuzosin in Pharmaceutical Preparations

2007 ◽  
Vol 4 (4) ◽  
pp. 496-501 ◽  
Author(s):  
M. Vamsi Krishna ◽  
D. Gowri Sankar
Keyword(s):  
Pharmaceutical Preparations ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Basic Medium ◽  
Coupling Reactions ◽  
Acetyl Acetone ◽  
Diazo Coupling ◽  
Optimum Reaction ◽  
Diazonium Ion

Simple, rapid and sensitive spectrophotometric procedures were developed for the analysis of Alfuzosin hydrochloride (AFZ) in pure form as well as in pharmaceutical formulations. The methods are based on the reaction of AFZ with nitrite in acid medium to form diazonium ion, which is coupled with ethoxyethylenemaleic ester (Method A) or ethylcyanoacetate (Method B) or acetyl acetone (method C) in basic medium to form azo dyes, showing absorption maxima at 440, 465 and 490 nm respectively. Beer’s law is obeyed in the concentration of 4-20 μg/mL of AFZ for methods A, B and 3-15 μg/mL of AFZ for method C. The molar absorptivity and sandell’s sensitivity of AFZ- ethoxyethylenemaleic ester, AFZ- ethylcyanoacetate and AFZ-acetyl acetone are1.90 × 104, 0.022; 1.93 × 104, 0.021 and 2.67 × 104L mole-1cm-1, 0.015 μg cm-2respectively. The optimum reaction conditions and other analytical parameters were evaluated. The methods were successfully applied to the determination of AFZ in pharmaceutical formulations.

scholarly journals Indirect spectrophotometric determination of gentamicin and vancomycin antibiotics based on their oxidation by potassium permanganate

2006 ◽  
Vol 4 (4) ◽  
pp. 708-722 ◽  
Author(s):  
Akram El-Didamony ◽  
Alaa Amin ◽  
Ahmed Ghoneim ◽  
Ayman Telebany
Keyword(s):  
Acid Medium ◽  
Potassium Permanganate ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Reaction Conditions ◽  
Subsequent Determination ◽  
Optimum Reaction ◽  
Acid Orange Ii ◽  
Sulphuric Acid Medium

AbstractFour simple, accurate, sensitive and economical procedures (A–D) for the estimation of gentamicin sulphate and vancomycin hydrochloride, both in pure form and in pharmaceutical formulations have been developed. The methods are based on the oxidation of the studied drugs by a known excess of potassium permanganate in sulphuric acid medium and subsequent determination of unreacted oxidant by reacting it with amaranth dye (method A), acid orange II (method B), indigocarmine (method C) and methylene blue (method D), in the same acid medium at a suitable λmax=521, 485, 610 and 664 nm, respectively. The reacted oxidant corresponds to the drug content. Regression analysis of Beer-Lambert plots showed good correlations in the concentration ranges 4–8, 3–8, 4–9 and 5–9 µg ml−1 with gentamicin and 4–8, 1.5–4, 1.5–4 and 3.5–5.5 µg ml−1 with vancomycin for methods A, B, C, and D, respectively. The molar absorptivity, sandell sensitivity, detection and quantification limits were calculated. The stoichiometric ratios for the cited drugs were studied. The optimum reaction conditions and other analytical parameters were evaluated. The influence of the substance commonly employed as excipients with these drugs were studied. The proposed methods were applied to the determination of these drugs in pharmaceutical formulations. The results have demonstrated that the methods are equally accurate and reproducible as the official methods.

scholarly journals Determination of Nickel in End-Fitting of Spoolable Reinforced Plastic Line Pipe

2018 ◽  
Vol 142 ◽  
pp. 01002
Author(s):  
Xiaodong Shao
Keyword(s):  
Ammonium Persulfate ◽  
Reaction Conditions ◽  
Line Pipe ◽  
Acid Gas ◽  
Determination Of Nickel ◽  
Reinforced Plastic ◽  
Relative Standard ◽  
Optimum Reaction ◽  
Fitting In

Spoolable reinforced plastic line pipe will be widely used in the exploitation of acid gas and oil wells. End-fitting is a mechanical device that forms the transition from the spoolable reinforced plastic line pipe to the connector. It was well known that nickel was an important element in the end-fitting. In this paper, a novel spectrophotometric method was described for determination of nickel in the end-fitting of spoolable reinforced plastic line pipe. The method was based on the color reaction between nickel and dimethylglyoxime, which was favored in an alkaline medium, producing a red compound in the presence of ammonium persulfate as an oxidant. Under the optimum reaction conditions the absorption value was proportional to the concentration of nickel in the range of 0.080~0.50% (R2 = 0.9999), and the relative standard deviation was less than 3.0% (n=5). The proposed method was applied successfully to determine nickel in end-fitting of spoolable reinforced plastic line pipe.

Determination of the Optimum Reaction Conditions for the PCR in Kenyan Musa Germplasm

2002 ◽  
Vol 2 (2) ◽  
pp. 64-66 ◽  
Author(s):  
Justus M. Onguso . ◽  
Esther M. Kahangi . ◽  
Douglas W. Ndiritu . ◽  
Fusao Mizutani .
Keyword(s):  
Reaction Conditions ◽  
Optimum Reaction

scholarly journals Efficient removal of Hg2+, Cd2+ and Pb2+ from aqueous solution and mixed industrial wastewater using a designed chelating ligand, 2-pyridyl-N-(2′-methylthiophenyl) methyleneimine (PMTPM)

2019 ◽  
Vol 79 (6) ◽  
pp. 1092-1101 ◽  
Author(s):  
Krishnendu Kumar Pobi ◽  
Biplab Mondal ◽  
Sumanta Nayek ◽  
Apurba K. Patra ◽  
Rajnarayan Saha
Keyword(s):  
Aqueous Solution ◽  
Industrial Wastewater ◽  
Chelating Agent ◽  
Chloride Ions ◽  
Coordination Geometry ◽  
Reaction Conditions ◽  
X Ray ◽  
Stability Order ◽  
Optimum Reaction

Abstract The present study is focused on the removal of Hg2+, Cd2+ and Pb2+ ions from aqueous solution using a tridentate chelating agent, 2-pyridyl-N-(2′-methylthiophenyl) methyleneimine (PMTPM); and applicability of such removal from industrial wastewater using PMTPM is also investigated. The results showed that the metal ions removal efficiency using PMTPM was in the order of Hg2+(99.46%) > Cd2+(95.42%) > Pb2+(94.54%) under optimum reaction conditions (L:M2+ = 3:1, pH = 9, time = 24 h, temp. = 30 °C). Formed chelated complexes such as [Hg(PMTPM)Cl2] (1), [Cd(PMTPM)Cl2] (2) and [Pb(PMTPM)Cl2] (3) were characterized by numerous spectroscopic tools and X-ray structure determination of a representative complex of Hg2+. In the X-ray structure of [Hg(PMTPM)Cl2], 1, the Hg2+ adopted a distorted tetrahedral coordination geometry surrounding two N donors of PMTPM and two chloride ions. A similar coordination geometry surrounding the respective metal centres in 2 and 3 was established. The thermogravimetric analysis (TGA) revealed a stability order of [Cd(PMTPM)Cl2] > [Hg(PMTPM)Cl2] > [Pb(PMTPM)Cl2]. Further the comparative metal leaching behaviour of these chelate complexes exhibited higher stability in alkaline solution than in acidic. Moreover, PMTPM was applied in real mixed industrial wastewater with alkaline pH, and adequate removals of toxic metals were achieved.

scholarly journals SPECTROFLUORIMETRIC DETERMINATION OF EOSIN CHEMILUMINESCENCE SYSTEM FOR THE ANALYSIS OF DABIGATRAN IN PHARMACEUTICAL FORMULATIONS

2019 ◽  
pp. 104-108
Author(s):  
DHANAPAL Y ◽  
SRUDHIVINOD V ◽  
MOHAMAD WASEEM A
Keyword(s):  
Method Development ◽  
Pharmaceutical Formulations ◽  
Calibration Graph ◽  
Eosin Y ◽  
Linear Calibration ◽  
Reaction Conditions ◽  
Quenching Effect ◽  
Spectrofluorimetric Determination ◽  
Optimum Reaction

Objectives: The objectives of this study were to develop a rapid, simple, and economical spectrofluorometric method for quantification of dabigatran from marketed formulation and its principle involved based on the protonated process of a binary mixture complex formation with eosin Y. Methods: A simple and precise spectrofluorometric technique was applied for the method development. It depends on measuring the quenching effect of the drug on the native fluorescence of eosin at excitation under the optimum reaction conditions. Results: The reaction linear calibration graph constructed between the fluorescence quenching valves flouresence intensity (ΔF) and the concentration ranges of 5–50 μg/ml. Spectrofluorometric analytical performance was validated by accuracy, precision, and specificity, and the results were satisfactory. Conclusion: This method was to develop a fast, simple, and economically applied successfully for the assay, and qualification of dabigatran tablet contains drug, also with different coformulated pharmaceutical formulations.

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