scholarly journals Determination of Traces of Pd(II) in Spiked Samples by Using 3,4-Dihydroxybenzaldehydeisonicotinol-hydrazone as a Chelating Agent with UV Visible Spectrophotometer

2011 ◽  
Vol 8 (1) ◽  
pp. 217-225 ◽  
Author(s):  
S. Lakshmi Narayana ◽  
C. Ramachandraiah ◽  
A. Varada Reddy ◽  
Dongyeun Lee ◽  
Jaesool Shim
Keyword(s):  
Metal Ion ◽  
Regression Coefficient ◽  
Chelating Agent ◽  
Molar Absorptivity ◽  
Inexpensive Method ◽  
Colored Complex ◽  
Major Cations ◽  
Uv Visible ◽  
Metal Ligand

A simple, rapid, sensitive and inexpensive method has been developed for the determination of trace amounts of palladium(II) using 3,4-dihydroxybenzaldehydeisonicotinoylhydrazone (3,4-DHBINH). The metal ion gives a yellow colored complex with 3,4-DHBINH in acetate buffer of pH 3.0 with 1:1 (metal: ligand) composition. The complex shows maximum absorption at 380 nm. Beer’s law is obeyed in the range 0.5-20.0 ppm of Pd(II). The molar absorptivity, Sandell’s sensitivity and detection limit were found to be 0.53×104L mol-1cm-1, 0.02 μg cm-2and 0.0948 μg mL-1, respectively. The correlation coefficient and regression coefficient of the Pd(II)-3,4-DHBINH complex were 1.08 and 0.04 respectively. Major cations and anions did not show any interference. Anti-microbial activity of the Pd(II)-3,4-DHBINH has been studied. The developed method has been successfully applied to the analysis of Pd(II) in spiked samples. Comparing the results with those obtained using an atomic absorption spectrophotometer tested the validity of the method

scholarly journals Spectrophotometric Determination of Selenium in Various Samples Using 5,6-Diaminouracil Hydrochloride (DAUH)

2015 ◽  
Vol 61 ◽  
pp. 128-136 ◽  
Author(s):  
Salwa Fares Rassi
Keyword(s):  
Acidic Medium ◽  
Metal Ion ◽  
Molar Absorptivity ◽  
Molar Ratio ◽  
Ratio Method ◽  
Colored Complex ◽  
Molar Ratio Method ◽  
Analytical Reagent ◽  
Color Reactions

A simple, rapid and sensitive spectrophotometric method was developed for the determination of Se (IV) using 5,6-diaminouracil hydrochloride (DAUH) as an analytical reagent. The reagent has been synthesized and characterized using IR, 1H NMR. The metal ion in aqueous medium forms yellow colored complex with DAUH showing maximum absorbance at 343 nm. Hence, analytical studies were further carried out at 343 nm. The reagent reacts with selenium in acidic medium to form yellow colored 1:1 (M:L) complex . The color reactions are instantaneous and absorbance values remain constant for one week. The composition of the Se (IV) complex with DAUH was studied by the method of job’s continuous variation and molar ratio method. Beer’s law was obeyed in the range 0.2-15.0 μg mL−1of Se (IV). The molar absorptivity and Sandell’s sensitivity of the method were found to be 0.5×10+4 L.mol-1.cm-1and 0.031μg.cm-2 respectively. Since DAUH method is more sensitive, it was applied for the determination of selenium in samples.

Extractive Spectrophotometric Method for the Determination of Glibenclamide by Ion-Pair Complex in Pure Form and Pharmaceutical Formulation

2019 ◽  
Vol 9 (o3) ◽  
Author(s):  
RUAA MUAYAD MAHMOOD ◽  
HAMSA MUNAM YASSEN ◽  
SAMAR , NAJWA ISSAC ABDULLA AHMED DARWEESH ◽  
NAJWA ISSAC ABDULLA
Keyword(s):  
Spectrophotometric Method ◽  
Molar Absorptivity ◽  
Ion Pair ◽  
Pharmaceutical Formulation ◽  
Ratio Method ◽  
Colored Complex ◽  
Colored Product ◽  
Method Of Continuous Variation ◽  
Job's Method

Simple, rapid and sensitive extractive spectrophotometric method is presented for the determination of glibenclamide (Glb) based on the formation of ion-pair complex between the Glb and anionic dye, methyl orange (MO) at pH 4. The yellow colored complex formed was quantitatively extracted into dichloromethane and measured at 426 nm. The colored product obeyed Beer’s law in the concentration range of (0.5-40) μg.ml-1. The value of molar absorptivity obtained from Beer’s data was found to be 31122 L.mol-1.cm-1, Sandell’s sensitivity value was calculated to be 0.0159 μg.cm-2, while the limits of detection (LOD) and quantification (LOQ) were found to be 0.1086 and 0.3292 μg.ml-1, respectively. The stoichiometry of the complex created between the Glb and MO was 1:1 as determined via Job’s method of continuous variation and mole ratio method. The method was successfully applied for the analysis of pharmaceutical formulation.

VALIDATED RP-HPLC AND UV-SPECTROSCOPY METHODS FOR THE ESTIMATION OF DAPAGLIFLOZIN IN BULK AND IN TABLETS

INDIAN DRUGS ◽  
2017 ◽  
Vol 54 (03) ◽  
pp. 44-51
Author(s):  
B. Sabbagh ◽  
B. V. S. Lokesh ◽  
G. A. Akouwah ◽  
Keyword(s):  
Good Accuracy ◽  
Uv Spectroscopy ◽  
Linear Regression Analysis ◽  
Molar Absorptivity ◽  
Hplc Method ◽  
Rp Hplc ◽  
Accuracy And Precision ◽  
Significant Difference ◽  
Uv Visible

Two methods were developed for the determination of dapagliflozin (DAPA) in pure form and in tablets. The procedure utilized was UV-Visible Spectroscopy and RP-HPLC with PDA detector to quantify DAPA in bulk and tablets. The sensitive linear range was identified for both methods within 0.5-5.0μg/mL. The linear regression analysis was identified for both methods with correlation coefficient(r)>0.99. The LOD and LOQ values were found to be 0.05 μg/mL and 0.5 μg/mL for the method by UV-Spectroscopy. The molar absorptivity (ε) was calculated as 1.27 X 105 L.mol-1cm-1. The RP-HPLC method produced LOD and LOQ values of 1.0 ng/mL and 0.5 μg/mL. Both methods were simple, precise, reproducible to quantify the amount of unknown in bulk as well as in tablets and estimated accurately within the range of 100.0±0.5%. Statistical analysis was performed on the data obtained. There was no significant difference between the developed and reported methods with p>0.05. Both methods can be applied for routine analysis of DAPA in bulk and tablets with good accuracy and precision.

scholarly journals Nitroso-R-salt as a sensitive spectrophotometric reagent for the determination of paracetamol in pharmaceutical preparations

2009 ◽  
Vol 6 (3) ◽  
pp. 570-577
Author(s):  
Baghdad Science Journal
Keyword(s):  
Aqueous Solution ◽  
Statistical Difference ◽  
Pharmaceutical Preparations ◽  
Molar Absorptivity ◽  
Calibration Graph ◽  
Subsequent Reaction ◽  
Experimental Conditions ◽  
Colored Complex ◽  
British Pharmacopoeia

Nitroso-R-salt is proposed as a sensitive spectrophotometric reagent for the determination of paracetamol in aqueous solution. The method is based on the reaction of paracetamol with iron(III) and subsequent reaction with nitroso-R-salt to yield a green colored complex with maximum absorption at 720 nm. Optimization of the experimental conditions was described. The calibration graph was linear in the concentration range of 0.1 – 2.0 ?g mL-1 paracetamol with a molar absorptivity of 6.9 × 104 L mol-1 cm-1. The method was successfully applied to the determination of paracetamol in pharmaceutical preparations without any interference from common excipients. The method has been statistically evaluated with British Pharmacopoeia method and no statistical difference between methods was found at the 95% confidence level.

Preconcentration and Determination of Lead by Solidification of Floated Organic Drop Coupled with Nanodrop Spectrophotometry

2013 ◽  
Vol 829 ◽  
pp. 825-830 ◽  
Author(s):  
Ali Mazloomifar ◽  
Nafiseh Khatibi
Keyword(s):  
Sea Water ◽  
Chelating Agent ◽  
Limit Of Quantification ◽  
Liquid Phase Microextraction ◽  
Relative Standard ◽  
Preconcentration Factor ◽  
Uv Visible ◽  
Optimized Conditions ◽  
Sample Vial

The liquid-phase microextraction based on solidification of floating organic microdrop coupled with UV-visible spectrophotometer for preconcentration and determination of lead in the aqueous samples has been developed. In this technique, 20μL of 1-undecanol containing dithizone as the chelating agent (10-3mol L-1) was transferred to the water samples containing lead ions, and the solution was stirred for 25 min. The sample vial was cooled in an ice bath for 5 min. The solidified extract was transferred into a conical vial where it melted immediately, and then the organic phase was analyzed by Nanodrop spectrophotometer. Factors that influence the extraction and complex formation, such as pH, concentration of dithizone, extraction time, effect of ionic strenght, temperature and stirring rate were optimized. Under the optimized conditions, a preconcentration factor of 356, detection limit of 0.006 μgL-1, limit of quantification 0.018 μgL-1and a good relative standard deviation of 2.1% were obtained. The procedure was applied to sea water, mineral water and well water.

Capillary electrophoresis facilitates determination of metal complex stoichiometry by Job’s method of continuous variation

2013 ◽  
Vol 10 (5) ◽  
pp. 409 ◽  
Author(s):  
Nathan E. Boland ◽  
Alan T. Stone
Keyword(s):  
Capillary Electrophoresis ◽  
Chelating Agent ◽  
Formation Constants ◽  
Continuous Variation ◽  
Spectroscopic Characteristics ◽  
Peak Areas ◽  
Method Of Continuous Variation ◽  
Job's Method ◽  
Metal Ligand

Environmental context Knowledge of metal-chelating agent speciation is integral to our ability to predict and interpret the behaviour of synthetic chelating agents in the environment. Capillary electrophoresis can be used to separate metal–ligand complexes with similar spectroscopic characteristics but different stoichiometries, thereby providing insight into metal–ligand speciation that is not possible by any other technique. Here, we demonstrate the utility of capillary electrophoresis for the determination of metal–ligand stoichiometries and evaluate its limitations. Abstract Job’s method of continuous variation is a traditional method used to determine the stoichiometry of metal–ligand complexes. The method is often applied to whole-sample absorbance measurements but its utility is limited when two or more complexes are present at significant concentrations and have similar absorption spectra. Here we employ capillary electrophoresis (CE), which separates complexes on the basis of charge and hydrodynamic radii, to extend the capabilities of Job’s method. Solutions containing nickel(II) and diethylenetriaminepentaacetic acid (DTPA) yield three CE peaks. Job’s method plot maxima, based on areas for each of the three CE peaks, coincide with nickel(II)-to-DTPA ratios of 1 : 1 and 1 : 2, which correspond to two complexes previously identified using whole-sample measurements, plus a ratio of 3 : 2, which corresponds to a previously unreported complex. We demonstrate how CE peak areas and electromigration times can be used to determine complex stoichiometries and formation constants. We discuss the strengths and weaknesses of Job’s Method coupled with CE and implications for speciation determination in environmentally relevant systems.

scholarly journals UV-Vis Spectrophotometric Determination of Selected Heavy Metals (Pb, Cr, Cd and As) in Environmental, Water and Biological Samples with Synthesized Glutaraldehyde Phenyl Hydrazone as the Chromogenic Reagent

2021 ◽  
Vol 2 (3) ◽  
pp. 1-5
Author(s):  
Samuel Echioda ◽  
Adepeju Oluwabunmi Ogunieye ◽  
Salisu Salisu ◽  
Amina Abdulazeez Abdulrasheed ◽  
I. Y. Chindo ◽  
...  
Keyword(s):  
Spectrophotometric Determination ◽  
Biological Samples ◽  
Environmental Water ◽  
Molar Absorptivity ◽  
Ligand Complex ◽  
Chromogenic Reagent ◽  
Validity Range ◽  
Metal Ligand ◽  
Water And Biological Samples

A simple, sensitive, selective, and non-extractive UV-Vis spectrophotometric method for the determination of cadmium, lead, chromium, and arsenic in biological, soil and water samples using synthesized and characterized phenyl hydrazone; glutaraldehydephenyl hydrazone (GPH) as the chromogenic reagent was developed. GPH was synthesized as new chromogenic analytical reagents for the direct UV-Vis spectrophotometric determination of the selected metals of interest in a slightly acidic pH of 6.5-7.5 and 20 % dimethylformamide (DMF) solution to give stable coloured metal-ligand complexes. The reactions were instantaneous; the wavelengths of maximum absorptions were followed spectrophotometrically and noted. The reagent GPH revealed a wavelength of maximum absorption between 360.0 (Cr) to 395.0 nm for (Pb and As) at a working pH of 6.5 to 7.5 room temperature (37 °C). The reagent GPH had a molar absorptivity (L mol-1 cm-1) ranging from 2.213×104 (Pb) to 2.460×104 (As), a mole ratio of metal to ligand of 2:1, the detection limit (µg/g) ranging from 0.3432 (As) to 0.5250 (Pb) and the metal-ligand complex was stable for 0-48 hours. The reagents had a Beer’s law validity range (mg L-1) of 0.001 to 100. The Sandell’s sensitivities (µg/cm2) ranged from 0000409 (As) to 0.00499 (Pb) for APDH and 0.00406 (As) to 0.00452 (Pb) respectively. Large excess of cations and anions as possible interferences up to 15 folds were studied and do not interfere with the determination of the selected metals of interest. The developed method is highly selective for Cd, Pb, and Cr and As and was successfully used for the determination for the said elements in soil, water, and biological samples. The results of the developed methods were comparable with AAS and were found to be in good agreement. The method had very high precision and very good accuracy.

scholarly journals Spectrophotometric Determination of Sulfamethoxazole Based on Charge-Transfer Complexation with Sodium Nitroprusside

2017 ◽  
Vol 30 (3) ◽  
pp. 102
Author(s):  
Tariq Y. Mahmoud ◽  
Sarmad B. Dikran ◽  
Alaa K. Mohammed
Keyword(s):  
Charge Transfer ◽  
Sodium Nitroprusside ◽  
Pharmaceutical Preparation ◽  
Molar Absorptivity ◽  
Amine Hydrochloride ◽  
Colored Complex ◽  
Central Composite Experimental Design ◽  
Charge Transfer Complexation ◽  
Good Agreement

   A simple, accurate and precise spectrophotometric method has been developed for the analysis of sulfamethoxazole (SMZ) in pure form and pharmaceutical preparation. The method involves a direct charge transfer complexation of sulfamethoxazole (SMZ) with sodium nitroprusside (SNP) in alkaline medium and the presence of hydroxyl amine hydrochloride. Variables affecting the formation of the formed orange colored complex were optimized following two approaches univariate and central composite experimental design (CCD) multivariate. Under optimum recommended conditions, the formed complex exhibits λmax at 512 nm and the method conforms Beer's law for SMZ concentration in the range of 5.0-150.0 (µg.mL-1) with molar absorptivity 1.139×103 L.mol-1.cm-1, and r = 0.9997. Analysis of SMZ pharmaceutical dosages shows a good agreement with the real amounts.

scholarly journals Spectrophotometric Methods for the Assay of Fluvoxamine Using Chromogenic Reagents

2010 ◽  
Vol 7 (4) ◽  
pp. 1539-1545
Author(s):  
V. Annapurna ◽  
G. Jyothi ◽  
V. Nagalakshmi ◽  
B. B. V. Sailaja
Keyword(s):  
Ascorbic Acid ◽  
Regression Analysis ◽  
Standard Error ◽  
Oxidative Coupling ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Method Of Least Squares ◽  
Spectrophotometric Methods ◽  
Uv Visible

Simple, accurate and reproducible UV-Visible spectrophotometric methods were established for the assay of FXA based on the oxidative coupling and condensation reactions. Condensation and coupling of the FXA with Ninhydrin-Ascorbic acid is proposed in method A. Method B includes complexation of FXA with cobalt thiocyanate. The ligating property of FXA with sodium nitro prusside is incorporated in method C. The optical characteristics such as Beers law limits, molar absorptivity and Sandell’s sensitivity for the methods (A-C) are given. Regression analysis using the method of least squares was made to evaluate the slope(b), intercept(a) and correlation coefficient (r) and standard error of estimation (Se) for each system. Determination of FXA in bulk form and in pharmaceutical formulations were also incorporated.

scholarly journals Simple, Rapid and Sensitive UV-Visible Spectrophotometric Method for Determination of Antidepressant Amitriptyline in Pharmaceutical Dosage Forms

2013 ◽  
Vol 2013 ◽  
pp. 1-5
Author(s):  
Pankaj Soni ◽  
Deepak Sinha ◽  
Rajmani Patel
Keyword(s):  
Antidepressant Drug ◽  
Pharmaceutical Preparations ◽  
Correlation Coefficients ◽  
Molar Absorptivity ◽  
Tricyclic Antidepressant ◽  
Simple Approach ◽  
Colour Intensity ◽  
Pharmaceutical Dosage Forms ◽  
Uv Visible

The paper describes a new and simple approach for spectrophotometric determination of tricyclic antidepressant drug amitriptyline. Enhancement of the colour intensity of the Fe(III)-SCN−complex on addition of the drug amitriptyline forms the basis of the proposed method. The value of molar absorptivity of the Fe(III)-SCN−amitriptyline ion pair complex in terms of the drug lies in the range of (2.82–3.36) × 103 L·mol−1·cm−1at the absorption maximum 460 nm. The detection limit of the method was 0.3 μg·mL−1. The slope, intercept, and correlation coefficients for the present method were found to be 0.008, 0.002, and +0.998, respectively. The effect of analytical variables on the determination of the drug and the composition of the complex are discussed in the paper. The method is applicable in the determination of amitriptyline in pharmaceutical preparations.

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