scholarly journals 2-Hydroxy-1-naphthaldehyde-P-hydroxybenzoichydrazone: A New Chromogenic Reagent for the Determination of Thorium(IV) and Uranium(VI)

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
V. S. Anasuya Devi ◽  
V. Krishna Reddy
Keyword(s):  
Detection Limit ◽  
Simultaneous Determination ◽  
Uranium Content ◽  
Molar Absorptivity ◽  
Spectrophotometric Methods ◽  
Maximum Absorbance ◽  
Highly Sensitive ◽  
Beer's Law ◽  
Beer’S Law

Simple, sensitive, selective, direct, derivative, and simultaneous spectrophotometric methods are developed for the determination of uranium and thorium individually and simultaneously. The methods are based on the reaction of 2-hydroxy-1-naphthaldehyde-p-hydroxybenzoichydrazone (HNAHBH) with thorium(IV) and uranium(VI). HNAHBH reacts with thorium and uranium at pH 6.0 forming stable yellow and reddish brown coloured complexes, respectively. [Th(IV)-HNAHBH] complex shows maximum absorbance at 415 nm. Beer’s law is obeyed over the concentration range 0.464–6.961 μg mL−1with a detection limit of 0.01 μg mL−1and molar absorptivity,ε, 3.5 × 104 L mol−1 cm−1. Maximum absorbance shown by [U(VI)-HNAHBH] complex is at 410 nm with Beer’s law range 0.476–7.140 μg mL−1, detection limit 0.139 μg mL−1and molar absorptivity,ε, 1.78 × 104 L mol−1 cm−1. Highly sensitive and selective second-order derivative methods are reported for the direct and simultaneous determination of Th(IV) and U(VI) using HNAHBH. The applicability of the developed methods is tested by analyzing water, ore, fertilizer, and gas mantle samples for thorium and uranium content.

scholarly journals Spectrophotometric Determination of Iron(II) and Cobalt(II) by Direct, Derivative, and Simultaneous Methods Using 2-Hydroxy-1-Naphthaldehyde-p-Hydroxybenzoichydrazone

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
V. S. Anusuya Devi ◽  
V. Krishna Reddy
Keyword(s):  
Detection Limit ◽  
Cobalt Content ◽  
Molar Absorptivity ◽  
Order Derivative ◽  
Spectrophotometric Methods ◽  
Biological Water ◽  
Highly Sensitive ◽  
Beer's Law ◽  
Beer’S Law

Optimized and validated spectrophotometric methods have been proposed for the determination of iron and cobalt individually and simultaneously. 2-hydroxy-1-naphthaldehyde-p-hydroxybenzoichydrazone (HNAHBH) reacts with iron(II) and cobalt(II) to form reddish-brown and yellow-coloured [Fe(II)-HNAHBH] and [Co(II)-HNAHBH] complexes, respectively. The maximum absorbance of these complexes was found at 405 nm and 425 nm, respectively. For [Fe(II)-HNAHBH], Beer’s law is obeyed over the concentration range of 0.055–1.373 μg mL−1with a detection limit of 0.095 μg mL−1and molar absorptivityɛ, 5.6 × 104 L mol−1cm−1. [Co(II)-HNAHBH] complex obeys Beer’s law in 0.118–3.534 μg mL−1range with a detection limit of 0.04 μg mL−1and molar absorptivity,ɛof 2.3 × 104 L mol−1cm−1. Highly sensitive and selective first-, second- and third-order derivative methods are described for the determination of iron and cobalt. A simultaneous second-order derivative spectrophotometric method is proposed for the determination of these metals. All the proposed methods are successfully employed in the analysis of various biological, water, and alloy samples for the determination of iron and cobalt content.

scholarly journals A Rapid Extractive Spectrophotometric Method for the Determination of Tin with 6-Chloro-3-hydroxy-2-(2′-thienyl)-4-oxo-4H-1-benzopyran

2014 ◽  
Vol 2014 ◽  
pp. 1-6 ◽  
Author(s):  
Ramesh Kataria ◽  
Harish Kumar Sharma
Keyword(s):  
Spectrophotometric Method ◽  
Metal Ion ◽  
Molar Absorptivity ◽  
Platinum Metals ◽  
Maximum Absorbance ◽  
Beer's Law ◽  
Beer’S Law ◽  
Hcl Medium

An extractive spectrophotometric method for the determination of the trace amounts of tin has been carried out by employing 6-chloro-3-hydroxy-2-(2′-thienyl)-4-oxo-4H-1-benzopyran (in acetone) (CHTB) for the complexation of the metal ion in HCl medium. The colored species thus produced is quantitatively extracted into dichloromethane and shows the maximum absorbance at 432–437 nm. The method obeys Beer’s law in the range 0.0–1.3 μg mL−1 of tin with molar absorptivity and Sandell’s sensitivity of 5.81×104 L mol−1 cm−1 and 0.0020 μg Sn cm−2, respectively, at 435 nm. The method is highly selective and free from the interference of a large number of elements including platinum metals. The ratio of metal to ligand in the extracted species is 1 : 2. Utilizing this method, the analysis of various synthetic and technical samples including gun metal and tin can have been carried out satisfactorily.

scholarly journals Redox-Reaction Based Spectrophotometric Assay of Isoniazid in Pharmaceuticals

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
N. Swamy ◽  
K. N. Prashanth ◽  
K. Basavaiah
Keyword(s):  
Prussian Blue ◽  
Redox Reaction ◽  
Molar Absorptivity ◽  
Spectrophotometric Assay ◽  
Commercial Formulation ◽  
Spectrophotometric Methods ◽  
Ich Guidelines ◽  
Beer's Law ◽  
Beer’S Law

Two spectrophotometric methods are described for the determination of isoniazid (INH) in pharmaceuticals. In the first method (FCR method), INH is reacted with Folin-Ciocalteu reagent in Na2CO3 medium and the resulting blue colored chromogen measured at 760 nm. Iron(II), formed as a result of reaction between INH and iron(III), is made to react with ferricyanide, and the resulting Prussian blue is measured at 760 nm, basing the second method (FFC method). The conditions for better performance are optimized. Beer’s law is obeyed in the concentration ranges 0.5–10 and 0.2–3.0 μg mL−1 for FCR method and FFC methods, respectively, with corresponding molar absorptivity values of 1.12×104 and 4.55×104 L mol−1 cm−1. The methods are validated for accuracy, precision, LOD, LOQ, robustness, and ruggedness as per the current ICH guidelines. The validated methods were successfully applied to quantify INH in its commercial formulation with satisfactory results; hence the methods are suitable for isoniazid determination in bulk drugs and pharmaceuticals.

scholarly journals 2-(4-Diethylaminostyryl)-1,3,3-trimethyl-5-thiocyanato-3H-indolium chloride as a new reagent for indirect spectrophotometric red-ox determination of Osmium (VI)

2008 ◽  
Vol 10 (2) ◽  
pp. 17-19
Author(s):  
Zholt Kormosh ◽  
Svitlana Korolchuk
Keyword(s):  
Complex Anion ◽  
Molar Absorptivity ◽  
Reaction Conditions ◽  
Spectrophotometric Detection ◽  
Highly Sensitive ◽  
Beer's Law ◽  
Beer’S Law ◽  
Redox Method

2-(4-Diethylaminostyryl)-1,3,3-trimethyl-5-thiocyanato-3H-indolium chloride as a new reagent for indirect spectrophotometric red-ox determination of Osmium (VI) A highly sensitive indirect spectrophotometric redox method for the determination of osmium is reported on. The method is based on the oxidation of iodide by osmium (VI) and the spectrophotometric detection of the liberated iodine in the form of complex anion associate with 2-(4-diethylaminostyryl)-1,3,3-trimethyl-5-thiocyanato-3H-indolium chloride reagent. The appropriate reaction conditions have been established. The molar absorptivity is (0.2-1.2)·105 dm3/mol·cm at 589.5 nm wavelength. The absorbance of the coloured extracts obeys the Beer's law in the range to 7.6 mg/dm3 of Os(VI).

scholarly journals UV Spectrophotometric Estimation of Acipimox inBulk and Capsule Dosage Form

2009 ◽  
Vol 6 (4) ◽  
pp. 1117-1120 ◽  
Author(s):  
A. Elphine Prabahar ◽  
B. Thangabalan ◽  
R. Kalaichelvi ◽  
P. Vijayaraj Kumar
Keyword(s):  
Correlation Coefficient ◽  
Spectrophotometric Method ◽  
Dosage Form ◽  
Ultra Violet ◽  
Molar Absorptivity ◽  
Distilled Water ◽  
Maximum Absorbance ◽  
Beer's Law ◽  
Beer’S Law

A new simple, rapid, accurate, sensitive and precise spectrophotometric method in ultra violet region has been developed for determination of acipimox (ACX) in bulk and capsule dosage form. Acipimox exhibited maximum absorbance at 231 nm with apparent molar absorptivity of 1.5104 × 104in distilled water. Beer’s law was found to be obeyed in the concentration range 1-10 μg mL-1. Correlation coefficient was found to be 0.9998. The developed method was validated respect to linearity, precision, accuracy. The proposed method is useful for the routine estimation of ACX in bulk and capsule dosage form.

scholarly journals Spectrophotometric Method for the Determination of Carboxin in its Formulations and Environmental Samples

2011 ◽  
Vol 8 (4) ◽  
pp. 1680-1685 ◽  
Author(s):  
C. Swarna ◽  
K. Purushotham Naidu ◽  
G. Nagendrudu ◽  
N. V. S. Naidu ◽  
K. Saraswathi
Keyword(s):  
Oxidative Coupling ◽  
Environmental Samples ◽  
Molar Absorptivity ◽  
Spectrophotometric Methods ◽  
Beer's Law ◽  
Label Claim ◽  
Colored Product ◽  
Beer’S Law ◽  
Good Agreement

Simple, precise, rapid, sensitive and accurate spectrophotometric methods have been developed for the estimation of carboxin in pure form and in its formulations. The first method is based on oxidative coupling of carboxin with 1,10-phenonthrolin in presence of ferric chloride to form orange colored product with λmaxof 510 nm. The product obeyed Beer's law in the concentration range 1-10 mL (10 to 100 µg/mL) with molar absorptivity of 1.1425×103Sandell's sensitivity 0.2061. The second method is based on the reaction of carboxin with 2,2'-bipyridine to form orange red colored product exhibiting λmaxof 522 nm with molar absorptivity, Sandell's sensitivity 2.2605×103, 0.1041 respectively. It obeys Beer's law in the concentration range of 0.5-50 mL (5 to 50 µg/mL). The assay of results was found to be in good agreement with label claim.

scholarly journals Rapid Spectrophotometric Determination of Phenoxazine

2010 ◽  
Vol 7 (2) ◽  
pp. 1001-1005
Author(s):  
Baghdad Science Journal
Keyword(s):  
Detection Limit ◽  
Spectrophotometric Determination ◽  
Acidic Medium ◽  
Absorption Maximum ◽  
Aqueous Samples ◽  
Economic Method ◽  
Beer's Law ◽  
Beer’S Law ◽  
The Stability

A rapid high sensitive and inexpensive economic method has been developed for the Determination of phenoxazine by using molecular spectrophotometry. The method is based on the oxidation of phenoxazine by potassium (meta)periodate in acidic medium. The oxidation conditions were selected to enhance the sensitivity and the stability of the pink colored species which shows an absorption maximum at 530 nm. The Beer’s law was obeyed for phenoxazine concentration range from 1 to 6 µg mL-1 with 0.003 µg mL-1 detection limit and provided variation coefficients between 0.4 to 1.7 %. This method was successfully applied for the determination of phenoxazine in aqueous samples

Spectrophotometric Determination of Pyridoxine Hydrochlorine in Pharmaceutical Preparations and Foods

1997 ◽  
Vol 80 (6) ◽  
pp. 1368-1373 ◽  
Author(s):  
Kailasam Srtvidya ◽  
Natesan Balasubramanian
Keyword(s):  
Pharmaceutical Preparations ◽  
Molar Absorptivity ◽  
Spectrophotometric Assay ◽  
Stable Complex ◽  
Pyridoxine Hydrochloride ◽  
Beer's Law ◽  
Rice Samples ◽  
Beer’S Law ◽  
Aqueous Volume

Abstract An easy and sensitive spectrophotometric assay of pyridoxine is described. The procedure is based on formation of an azo dye by the reaction of pyridoxine with diazotized 2,4-dinitroaniline followed by the reaction of the dye with Hg2+ ions to form a stable complex with maximum absorbance at 545 nm. The system obeys Beer’s law for 4–75 μg pyridoxine hydrochloride in an overall aqueous volume of 25 mL (correlation coefficient, 0.9998). On extraction into 5 mL butan-1-ol, the system obeys Beer’s law in the range 0.8–15 μg pyridoxine hydrochloride at 545 nm. The color is stable for 60 min in both aqueous and organic phases (molar absorptivity, 3.7 × 104 L/mol · cm; coefficient of variation, 3.1%, n = 10). The pyridoxine contents of pharmaceutical preparations, a processed foodstuff, and 2 rice samples were determined by using the proposed method. Assay reliability was established by recovery studies and parallel determination using a reported method.

scholarly journals Sensitive Spectrophotometric Methods for the Determination of Ascorbic Acid

2008 ◽  
Vol 5 (1) ◽  
pp. 10-15 ◽  
Author(s):  
H. D. Revanasiddappa ◽  
M. A. Veena
Keyword(s):  
Ascorbic Acid ◽  
Acid Medium ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Spectrophotometric Methods ◽  
Maximum Absorbance ◽  
Hydrochloric Acid Medium ◽  
Subsequent Determination ◽  
Sulphuric Acid Medium

Two simple and sensitive spectrophotometric methods (A and B) have been described for the determination of ascorbic acid. Method A is based on the oxidation of ascorbic acid (AA) by known excess of Se(IV) in hydrochloric acid medium and subsequent determination of unreacted Se(IV) by reacting it with iodide in the same acid medium to liberate iodine, which react with starch to form a stable blue coloured iodine-starch complex, which shows maximum absorbance at 590 nm. Method B is based on the oxidation of ascorbic acid (AA) by known excess of Cr(VI) in sulphuric acid medium and the determination of unreacted Cr(VI) with diphenyl carbazide (DPC) under the same acidic medium to produce a stable red-violet coloured species, which shows a maximum absorbance at 550 nm. The reacted oxidants (in methods A and B) correspond to the AA content. The apparent molar absorptivity values are found to be 1.627×104and 1.641×104L mol-1cm-1for methods A and B, respectively. The proposed methods are simple, sensitive and suitable for the routine analysis of AA in pharmaceutical formulations and in real samples.

scholarly journals New Spectrophotometric Determination of Cefdinir by Batch Method and Cloud Point Extraction

2019 ◽  
Vol 30 (1) ◽  
pp. 85
Author(s):  
Omar Qusay Mezhir
Keyword(s):  
Detection Limit ◽  
Correlation Coefficient ◽  
Cloud Point ◽  
Azo Dye ◽  
Cloud Point Extraction ◽  
Diazonium Salt ◽  
Molar Absorptivity ◽  
Purple Colour ◽  
Beer's Law ◽  
Beer’S Law

In this study, new spectrophotometric methods were developed for estimation of cefdinir (CFD); the research consists of two methods. The first method depends on the conversion of function group amine in cefdinir to diazonium salt and then combined with the 2, 5-Dimethylphenol (2, 5-DMP) reagent in the alkaline medium. The formed azo dye has a purple colour with absorption intensity at λmax 510 nm. Concentration range was obeyed Beer's law at (1-50 μg / ml), correlation coefficient was 0.9998, molar absorptivity was 1.54 × 104 L.mol-1.cm-1 and the detection limit was 0.04 μg.ml-1. The second method is including cloud point extraction (CPE) of a trace amount of the formed azo dye in the first method followed by measuring with a UV-visible spectrophotometer. Concentration range that obeyed the Beer's law was (0.2-6 μg / ml), correlation coefficient was 0.9998, molar absorptivity was1.48×105 L.mol-1.cm-1, detection limit was 0.004 μg.ml-1, Pre-concentration factor was 25 and Distribution coefficient was 125.The proposed methods were applied and proved their compatibility for estimating of ingredient compound in pure samples and pharmaceuticals by comparing them with previous studies. Keyword: cefdinir, diazotization, cloud point extraction, 2, 5-Dimethylphenol.

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