scholarly journals Development of a spectrophotometric method for determination of ions Cu (II) C N- (2-hydroxybenzoyl) -N '- (p-tosil)hydrazine in ammonia media

2021 ◽  
Vol 11 (2) ◽  
pp. 103-113
Author(s):  
Yulia B. Elchishcheva ◽  
◽  
Ksenia S. Gorbunova ◽  
Petr T. Pavlov ◽  
◽  
...  
Keyword(s):  
Complex Compound ◽  
Spectrophotometric Method ◽  
Light Absorption ◽  
Conductometric Titration ◽  
Calibration Graph ◽  
Optimal Time ◽  
Optimal Conditions ◽  
Molar Ratios ◽  
Photometric Technique

A spectrophotometric method for the determination of Cu (II) ions with N- (2-hydroxybenzoyl) -N '- (p-tosyl) hydrazine (GBSH) in ammonia media has been developed. The optimal conditions for the formation of a complex compound are found: the wavelength of maximum light absorption; pH complexation; optimal time for color development; the amount of photometric reagent. Under optimal conditions of complexation of GBSG with Cu (Ⅱ) ions (λ = 401 nm, pH = 9.2, τ = 30 minutes, VGBSG = 3.75 ml), a calibration graph is constructed. The Bouguer-Lambert-Beer law is fulfilled in the range from 0.13 to 1.59 mg Cu (II) / 25 ml. The true molar light absorption coefficient of the complex compound of HBSG with Cu (Ⅱ) ions in the ammonia medium was 1480. The molar ratios in the solution of the complex compound were determined by the methods of saturation, shift of equilibria and conductometric titration - [Cu (Ⅱ)]: [HBSG] = 1: 1. According to Babko's method, the conditional constant of stability of the GBSG complex with Cu (Ⅱ) ions was calculated and it was 4.4 × 1010. The reproducibility and relative error of the developed photometric technique were determined by the method of mathematical statistics.

scholarly journals Determination of alkylbenzolsulphonic acid in aqueous solutions

2021 ◽  
Vol 11 (1) ◽  
pp. 17-29
Author(s):  
Svetlana A. Zabolotnykh ◽  
◽  
Svetlana A. Denisova ◽  
Keyword(s):  
Anionic Surfactant ◽  
Cationic Surfactants ◽  
Cetyltrimethylammonium Bromide ◽  
Tetrabutylammonium Bromide ◽  
Conductometric Titration ◽  
Calibration Graph ◽  
Optimal Conditions ◽  
Acid Base ◽  
Titration Method

The possibility of determining the anionic surfactant alkylbenzenesulfonic acid by various methods: potentiometric and conductometric titration with sodium hydroxide, conductometric titration with cationic surfactants (tetrabutylammonium bromide, cetyltrimethylammonium bromide) and spectrophotometry in the UV region, was considered. The acid-base titration method allows to determine the alkylbenzenesulfonic acid concentration in pure aqeous solutions. The content of anionic surfactant in the presence of nitric acid can be determined by conductometric titration with cetyltrimethylammonium bromide. The optimal conditions for alkylbenzenesulfonic acid spectrophotometric determination (light absorption maxima, linearity range of the calibration graph, molar absorption coefficient) have been established.

scholarly journals Spectrophotometric and Conductometric Determination of Clomiphene Citrate and Nefazodone HCl

2008 ◽  
Vol 5 (s2) ◽  
pp. 1069-1080 ◽  
Author(s):  
Wafaa S. Hassan ◽  
Mervat M. Hosny
Keyword(s):  
Spectrophotometric Method ◽  
Clomiphene Citrate ◽  
Pharmaceutical Preparations ◽  
Conductometric Titration ◽  
Ion Pair ◽  
Experimental Conditions ◽  
Relative Standard ◽  
Colored Complexes ◽  
Standard Deviations

Two accurate, rapid and simple spectrophotometric and conductometric methods were developed for the determination of clomiphene citrate (CMP) and nefazodone HCl (NFZ), the proposed methods depends upon the reaction of ammonium reineckate with the two studied drugs to form stable precipitate of ion-pair complexes, which was dissolved in suitable solvent. The pink colored complexes were determined colorimetrically at 509, 523.6 nm, respectively. Using the conductometric titration, the studied drugs could be evaluated in 50% (v/v) acetone in the range 60.02-540.18 and 63.3-443.1 μg mL-1for clomiphene citrate and nefazodone HCl, respectively. While for spectrophotometric method the ranges were 0.2-1.8 and 0.2-1.6 mg mL-1for clomiphene citrate and nefazodone HCl respectively. Various experimental conditions were studied. The results obtained showed good recoveries with relative standard deviations of 0.759 and 0.552%. The proposed procedures were applied successfully to the analysis of these drugs in their pharmaceutical preparations and the results were favourably comparable with the official and reference methods. The molar combining ratio reveal that (1:1) (drug : reagent) ion associates were formed.

scholarly journals Kinetic- spectrophotometric Method for the Determination of Naringenin in Pure and Supplements Formulations

2019 ◽  
Vol 16 (3) ◽  
pp. 0595
Author(s):  
ALmashhadani Et al.
Keyword(s):  
Prussian Blue ◽  
Correlation Coefficient ◽  
Spectrophotometric Method ◽  
Limit Of Detection ◽  
Fixed Time ◽  
Calibration Graph ◽  
Maximum Absorbance ◽  
Kinetic Spectrophotometric

          Simple, cheap, sensitive, and accurate kinetic- spectrophotometric method has been developed for the determination of naringenin in pure and supplements formulations. The method is based on the formation of Prussian blue. The product dye exhibits a maximum absorbance at 707 nm. The calibration graph of naringenin was linear over the range 0.3 to 10 µg ml-1 for the fixed time method (at 15 min) with a correlation coefficient (r) and percentage linearity (r2%) were of 0.9995 and 99.90 %, respectively, while the limit of detection LOD was 0.041 µg ml-1. The method was successfully applied for the determination of naringenin in supplements with satisfactory results.

scholarly journals Azo-Substitute of EthoxyAcridine – A New Reagent for Extraction-Photometric Determination of Tellurium (IV)

2016 ◽  
Vol 12 (11) ◽  
pp. 4476-4479
Author(s):  
N.I. Ismayilov ◽  
A.M. Pashajanov ◽  
G.R. Muradova
Keyword(s):  
Elemental Analysis ◽  
Spectrophotometric Method ◽  
Light Absorption ◽  
Photometric Determination ◽  
Chloride Complexes ◽  
Azo Group ◽  
Analytical Properties ◽  
Determination Methods ◽  
Physical And Chemical

We studied associates of halogen telluride (Cl, Br) with 9-amine-4-ethoxyacridine-6-azo-N-N′-diethylaniline (AEADEA) by spectrophotometric method. It was established that associates are extracted well with chloroform-acetone (3:2). We determined the compositions, physical and chemical and analytical properties of complexes (εk, βKD, D, R%). Maximum light absorption for chloride complexes is found to be λmax 520 nm, but for bromide complexes - λmax 530 nm. For establishing the composition of azo- substitute ofethoxyacridine the synthesized reagents were exposed to elemental analysis, as well titanometrictitration by azo group. We developed new extraction-photometric determination methods of tellurium. Lambert-Beer law is observed in the range 0.5-15 mkgTe at 5 ml medium.

scholarly journals A Simple Spectrophotometric Method for Determination of Glyoxylic Acid in Its Synthesis Mixture

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Mazhar Abdulwahed ◽  
Lamia Mamoly ◽  
Wael Bosnali
Keyword(s):  
Standard Deviation ◽  
Spectrophotometric Method ◽  
Glycolic Acid ◽  
Glyoxylic Acid ◽  
Reference Method ◽  
Recovery Ratio ◽  
Molar Ratios ◽  
Relative Standard ◽  
Reaction Stoichiometry

A new simple and reliable spectrophotometric method is described to determine glyoxylic acid in its synthesis reaction mixture containing oxalic acid, glycolic acid, acetic acid, glyoxal, and ethylene glycol by means of a modified Hopkins–Cole reaction between glyoxylic acid and tryptophan in presence of ferric chloride and concentrated sulphuric acid. The linear range of glyoxylic acid concentration is 0–0.028 M. The limits of detection (LOD) and quantitation (LOQ) are 0.0019 M and 0.00577 M, respectively. The LOD, LOQ, standard deviation, relative standard deviation, and recovery ratio of the proposed method are comparable with a selected HPLC reference method. Both methods displayed same precision and credibility. Reaction stoichiometry between tryptophan and glyoxylic acid is assumed to be 2 : 3. Reaction mechanism has been postulated based on identified molar ratios of reactants. Glyoxal gave a negative test with tryptophan although it is a dialdehyde.

scholarly journals A New Technique for Quantitative Determination of Dexamethasone in Pharmaceutical and Biological Samples Using Kinetic Spectrophotometric Method

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
Ali Mohammad Akhoundi-Khalafi ◽  
Masoud Reza Shishehbore
Keyword(s):  
Quantitative Determination ◽  
Spectrophotometric Method ◽  
Biological Samples ◽  
Reaction System ◽  
Calibration Graph ◽  
Experimental Conditions ◽  
Orange G ◽  
A New Technique ◽  
Kinetic Spectrophotometric

Dexamethasone is a type of steroidal medications that is prescribed in many cases. In this study, a new reaction system using kinetic spectrophotometric method for quantitative determination of dexamethasone is proposed. The method is based on the catalytic effect of dexamethasone on the oxidation of Orange G by bromate in acidic media. The change in absorbance as a criterion of the oxidation reaction progress was followed spectrophotometrically. To obtain the maximum sensitivity, the effective reaction variables were optimized. Under optimized experimental conditions, calibration graph was linear over the range 0.2–54.0 mg L−1. The calculated detection limit (3sb/m) was 0.14 mg L−1for six replicate determinations of blank signal. The interfering effect of various species was also investigated. The present method was successfully applied for the determination of dexamethasone in pharmaceutical and biological samples satisfactorily.

scholarly journals Investigation of nikel(II) complexing with 2,6-dimerkapto-4-methilphenol and aminophenols

2021 ◽  
Vol 21 (1) ◽  
pp. 31-43
Author(s):  
Kerim Avaz oglu Kuliev ◽  
◽  
Shafa Aga qizi Mamedova ◽  
Naiba Nasraddin qizi Efendiyeva ◽  
◽  
...  
Keyword(s):  
Light Absorption ◽  
Acidic Medium ◽  
Mixed Ligand Complex ◽  
Mixed Ligand ◽  
Optimal Conditions ◽  
Ligand Complex ◽  
Single Extraction ◽  
Determination Of Nickel ◽  
Physicochemical Methods

Complexing of nickel(II) with 2,6-dimercapto-4-methylphenol (DMMP) and hydrophobic amines was studied using physicochemical methods. Hydroxyl-containing amines-aminophenols (AP) were used as a hydrophobic amine. On the part of aminophenols, 2 (N, N-dimethylaminomethyl)-4-methylphenol (AP1), 2 (N, N-dimethylaminomethyl)-4-chlorophenol (AP2), and 2 (N, N-dimethylaminomethyl)-4-bromophenol (AP3) were used. Mixed-ligand complexes were formed in a weakly acidic medium (pHopt 4.6–6.4). Ni(II) is recovered by chloroform by 98.6–99.5% in the form of a mixed-ligand complex (MLC) per single extraction. The optimal conditions for the formation and extraction of these compounds are 1.12 × 10-3 mol/L concentration of DMMP and 0.88 × 10-3 mol/L – AP. Changing the concentration of the reagents does not change the composition of the complexes. MLC of Ni(II) with DMMP and AP are stable in aqueous and organic solvents and do not decompose within three days and for more than a month after extraction. The ratio of reacting components in MLC corresponds to Ni (II): DMMP : AP = 1 : 2 : 2. in the formation of MLC, the coordinating ion is Ni2+. Complexing proceeds with the displacement of a proton from a DMMP molecule. Maximum light absorption is observed at λ = 520–530 nm. The molar coefficients of light absorption are (3.78-3.95) × 10 4. Based on the obtained data photometric methods for the determination of nickel in various industrial and natural objects were developed.

scholarly journals Spectrophotometric determination of neomycin sulphate in tablets form via reaction with ninhydrin reagent

2019 ◽  
Vol 10 (2) ◽  
pp. 1392-1396 ◽  
Author(s):  
Khalaf F Alsamarrai ◽  
Menaa Abdulsalam Al-Abbasi ◽  
Eman Thiab Alsamarrai
Keyword(s):  
Spectrophotometric Determination ◽  
Spectrophotometric Method ◽  
Calibration Curve ◽  
Limit Of Detection ◽  
Basic Medium ◽  
Optimal Conditions ◽  
Limit Of Quantification ◽  
Maximum Absorbance ◽  
Ninhydrin Reagent

A new, sensitive, simple and cheap spectrophotometric method for the determination of Neomycin Sulphate (NEO) in pharmaceutical forms has been developed. The method is based on the reaction between NEO and NIN in basic medium. The maximum absorbance was at 574 nm. The conditions affecting the reaction were optimized. Under the optimal conditions, the calibration curve was linear over the range of 0.0002-0.0011 mol/L. The limit of detection and limit of quantification were 5.423×10-6 mol/L, and 1.643×10-5 mol/L, RSD% of seven replicate was 0.8217- 0.8321% and Rec% was between 99.2168-100.8857%. The proposed method was successfully applied to the determination of NEO tablets form.

scholarly journals Influence of Partial Pressures of Acetylene and Nitrogen upon Nitrogenase Activity of Species of Beijerinckia

1977 ◽  
Vol 30 (6) ◽  
pp. 593 ◽  
Author(s):  
IC MacRae
Keyword(s):  
Nitrogen Fixation ◽  
Spectrophotometric Method ◽  
Acetylene Reduction ◽  
Nitrogenase Activity ◽  
Optical Emission ◽  
Molar Ratios ◽  
Partial Pressures ◽  
Beijerinckia Indica

Acetylene reduction and nitrogen fixation by strains of Beijerinckia indica and B. lacticogenes increased with increased partial pressures of acetylene and nitrogen up to 80 kPa. The optical emission spectrophotometric method was used for the determination of 14N : 15N ratios. The molar ratios of acetylene to nitrogen varied greatly from the theoretical value.

scholarly journals A Simple Spectrophotometric Method for Determination of Glyoxylic Acid in Its Synthesis Mixture

2020 ◽  
Author(s):  
Mazhar Abdulwahed ◽  
Lamia Mamoly ◽  
Wael Bosnali
Keyword(s):  
Standard Deviation ◽  
Spectrophotometric Method ◽  
Glyoxylic Acid ◽  
Reference Method ◽  
Recovery Ratio ◽  
Molar Ratios ◽  
Relative Standard ◽  
Concentrated Sulfuric Acid ◽  
Reaction Stoichiometry

A submitted manuscript to International Journal of Analytical Chemistry:<div><br><div>A new spectrophotometric method is described to determine glyoxylic acid in its synthesis reaction mixture by means of a modified Hopkins-Cole reaction between glyoxylic acid and tryptophan in presence of ferric chloride and concentrated sulfuric acid. The linear range of glyoxylic acid concentration is 0 - 0.028 M. The LOD and LOQ are 0.0019 M and 0.00577 M, respectively. The LOD, LOQ, standard deviation, relative standard deviation and recovery ratio of the proposed method are comparable with a selected HPLC reference method. Both methods displayed same precision and credibility. Reaction stoichiometry between tryptophan and glyoxylic acid is assumed to be 2:3. Reaction mechanism has been postulated based on identified molar ratios of reactants. Glyoxal gave a negative test with tryptophan although it is a di-aldehyde. </div></div>

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