scholarly journals The Use of 7,7′,8,8′-Tetracyanoquinodimethane for the Spectrophotometric Determination of Some Primary Amines Application to Real Water Samples

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Theia'a N. Al-Sabha ◽  
Najwa M. Al-Karemy
Keyword(s):  
Charge Transfer ◽  
Quantitative Determination ◽  
Spectrophotometric Method ◽  
Aromatic Amines ◽  
Molar Absorptivity ◽  
Primary Amines ◽  
Charge Transfer Complexes ◽  
Buffer Solution ◽  
Real Water Samples

A sensitive, simple, and accurate spectrophotometric method was developed for the quantitative determination of some primary aliphatic and aromatic amines, that is, ethylamine, 1,2-diaminopropane, aniline, p-aminophenol, and benzidine. The method is based on the interaction of these amines in aqueous medium with 7,7′,8,8′-tetracyanoquinodimethane (TCNQ) reagent in the presence of a buffer solution and surfactant (in the case of aromatic amines) to form charge-transfer complexes measurable at maximum wavelengths ranging between 323 and 511 nm. Beer’s law is obeyed over the concentration ranges of 0.025 and 3.0 μg/mL and the molar absorptivity is ranged between 8.977 × 103and 5.8034 × 104 L·mol−1·cm−1for these amines. The method was applied for the determination of benzidine in the river, sea, and tap waters. The TCNQ complexes with the previously mentioned amines were formed in the ratio of 1 : 1 amine : TCNQ, and their stability constants ranged between 8.78 × 104and 1.844 × 105 L·mol−1.

scholarly journals Difference spectrophotometric method for the determination of Fluphenazine hydrochloride in tablets using peroxomonosulfate

2021 ◽  
Vol 9 (2) ◽  
pp. 64-71
Author(s):  
Mykola Blazheyevskiy ◽  
◽  
Valeriy Moroz ◽  
Olena Mozgova ◽  
◽  
...  
Keyword(s):  
Quantitative Determination ◽  
Spectrophotometric Determination ◽  
Spectrophotometric Method ◽  
Present Method ◽  
Molar Absorptivity ◽  
Limit Of Quantification ◽  
Derivatizing Agent ◽  
Sensitive Method

The oxidative derivatization method using potassium hydrogenperoxomonosulfate for the indirect spectrophotometric determination of Fluphenazine hydrochloride is presented. Potassium hydrogenperoxomonosulfate is introduced as a derivatizing agent for Fluphenazine hydrochloride, yielding the sulfoxide. This reaction product was successfully used for the spectrophotometric determination of the Fluphenazine hydrochloride. The UV spectroscopic detection of the sulfoxide proved to be a more robust and sensitive method. The elaborated method allowed the determination of Fluphenazine hydrochloride in the concentration range of 0.2-30 µg mL-1. The molar absorptivity at 349 nm is 5.6×103 (dm3cm-1mol-1). The limit of quantification, LOQ (10S) is 0.24 µg/mL. A new spectrophotometric technique was developed and the possibility of quantitative determination of Fluphenazine hydrochloride in tablets 5.0 mg was demonstrated. The present method is precise, accurate and excipients did not interfere. RSD for Fluphenazine Hydrochloride 5.0 mg tablets was 1.37 %.

scholarly journals Sensitive Spectrophotometric Determinations of Paracetamol and Protriptyline HCl Using 3-Chloro-7-hydroxy-4-methyl-2H-chromen-2-one

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Kumble Divya ◽  
Badiadka Narayana ◽  
Majal Sapnakumari
Keyword(s):  
Charge Transfer ◽  
Spectrophotometric Method ◽  
Charge Transfer Complex ◽  
Limit Of Detection ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Pharmaceutical Samples ◽  
Chromogenic Reagent ◽  
Detection And Quantification

A new spectrophotometric method is developed for the determination of Paracetamol (PCT) and protriptyline HCl (PTP) in pure forms and in pharmaceutical formulations. The experiment involves the use of 3-chloro-7-hydroxy-4-methyl-2H-chromen-2-one as a novel chromogenic reagent for the determination of PCT and PTP. The method is based on the formation of charge transfer complex between the drugs and chromogenic reagent. Beer's law is obeyed in the concentration ranges 10.00–60.00 µg mL−1 for PCT at 545 nm and 40.00–160.00 µg mL−1 for PTP at 468 nm. The molar absorptivity, Sandell, sensitivity, and limit of detection and quantification are also calculated. The method has been successfully applied for the determination of both PCT and PTP in pharmaceutical samples with acceptable results.

scholarly journals Utility of Charge Transfer and Ion-Pair Complexation for Spectrophotometric Determination of Eletriptan Hydrobromide in Pure and Dosage Forms

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Ayman A. Gouda ◽  
Ragaa El Sheikh ◽  
Rham M. El-Azzazy
Keyword(s):  
Charge Transfer ◽  
Correlation Coefficients ◽  
Standard Addition ◽  
Molar Absorptivity ◽  
Dosage Forms ◽  
Ion Pair ◽  
Charge Transfer Complexes ◽  
Alizarin Red ◽  
Relative Standard

Three simple, sensitive, and accurate spectrophotometric methods have been developed for the determination of eletriptan hydrobromide (ELT) in pure and dosage forms. The first two methods are based on charge transfer complex formation between ELT and chromogenic reagents quinalizarin (Quinz) and alizarin red S (ARS) producing charge transfer complexes which showed an absorption maximum at 569 and 533 nm for Quinz and ARS, respectively. The third method is based on the formation of ion-pair complex between ELT with molybdenum(V)-thiocyanate inorganic complex in hydrochloric acid medium followed by extraction of the colored ion-pair with dichloromethane and measured at 470 nm. Different variables affecting the reactions were studied and optimized. Beer's law is obeyed in the concentration ranges 2.0–18, 1.0–8.0, and 2.0–32 μg mL−1for Quinz, ARS, and Mo(V)-thiocyanate, respectively. The molar absorptivity, Sandell sensitivity, detection, and quantification limits are also calculated. The correlation coefficients were ≥0.9994 with a relative standard deviation (R.S.D%.) of ≤0.925. The proposed methods were successfully applied for simultaneous determination of ELT in tablets with good accuracy and precision and without interferences from common additives, and the validity is assessed by applying the standard addition technique, which is compared with those obtained using the reported method.

scholarly journals Spectrophotometric Determination of Mycophenolate Mofetil as Its Charge-Transfer Complexes with Twoπ-Acceptors

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
K. B. Vinay ◽  
H. D. Revanasiddappa ◽  
M. S. Raghu ◽  
Sameer. A. M. Abdulrahman ◽  
N. Rajendraprasad
Keyword(s):  
Mycophenolate Mofetil ◽  
Charge Transfer ◽  
Correlation Coefficients ◽  
Reference Method ◽  
Standard Addition ◽  
Molar Absorptivity ◽  
Charge Transfer Complexes ◽  
Complexation Reaction ◽  
Chloranilic Acid

Two simple, selective, and rapid spectrophotometric methods are described for the determination of mycophenolate mofetil (MPM) in pure form and in tablets. Both methods are based on charge-transfer complexation reaction of MPM with p-chloranilic acid (p-CA) or 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in dioxane-acetonitrile medium resulting in coloured product measurable at 520 nm (p-CA) or 580 nm (DDQ). Beer’s law is obeyed over the concentration ranges of 40–400 and 12–120 μg mL−1MPM for p-CA and DDQ, respectively, with correlation coefficients (r) of 0.9995 and 0.9947. The apparent molar absorptivity values are calculated to be1.06×103and3.87×103 L mol−1 cm−1, respectively, and the corresponding Sandell’s sensitivities are 0.4106 and 0.1119 μg cm−1. The limits of detection (LOD) and quantification (LOQ) are also reported for both methods. The described methods were successfully applied to the determination of MPM in tablets. Statistical comparison of the results with those of the reference method showed excellent agreement. No interference was observed from the common excipients present in tablets. Both methods were validated statistically for accuracy and precision. The accuracy and reliability of the methods were further ascertained by recovery studiesviastandard addition procedure.

scholarly journals Spectrophotometric study on the charge transfer complex between sumatriptan succinate and some π-acceptors and alizarin derivatives

2013 ◽  
Vol 19 (4) ◽  
pp. 529-540 ◽  
Author(s):  
Sheikh El ◽  
Ayman Gouda ◽  
Rham El-Azzazy
Keyword(s):  
Charge Transfer ◽  
Standard Addition ◽  
Spectrophotometric Study ◽  
Molar Absorptivity ◽  
Charge Transfer Complexes ◽  
Alizarin Red ◽  
Spectrophotometric Methods ◽  
Sumatriptan Succinate ◽  
Relative Standard

A facile, accurate, sensitive and validated spectrophotometric methods for the determination of sumatriptan succinate (SMT) in pure and in dosage forms are described. The methods are based on the formation of charge transfer products between SMT and chromogenic reagents 2,3-dichloro-5,6 dicyano-p-benzoquinone (DDQ), 7,7,8,8-tetracyanoquinodimethane(TCNQ), quinalizarin (Quiz) and alizarin red S (ARS) producing charge transfer complexes which showed an absorption maximum at 461, 841, 567 and 529 nm for DDQ, TCNQ, Quiz and ARS, respectively. The optimization of the reaction conditions such as the type of solvent, reagent concentration and reaction time were investigated. Beer?s law is obeyed in the concentration ranges 1.0-80 mg mL-1. The molar absorptivity, Sandell sensitivity, detection and quantification limits are also calculated. The correlation coefficient was ?0.9994 with a relative standard deviation (R.S.D.) of ? 1.08. The proposed methods were successfully applied for determination of sumatriptan in tablets with good accuracy and precision and without interferences from common additives by applying the standard addition technique. Developed methods have been validated statistically for their accuracy, precision, sensitivity, selectivity, robustness and ruggedness as per ICH guidelines and the results compared favourably with those obtained using the reported method.

scholarly journals Spectrophotometric Determination of Some Hydrazine Derivatives Using 2,3-Dichloro-5,6-Dicyano-p-Benzoquinone

1999 ◽  
Vol 82 (2) ◽  
pp. 239-243 ◽  
Author(s):  
Sheikha Mohamed Al-Ghannam ◽  
Amina Mohamed El-Brashy ◽  
Laila Abdel-Rahman Al-Hussein
Keyword(s):  
Charge Transfer ◽  
Spectrophotometric Determination ◽  
Spectrophotometric Method ◽  
Pharmaceutical Formulations ◽  
Charge Transfer Complexes ◽  
Hydrazine Derivatives ◽  
Unit Dose ◽  
The Individual

Abstract A simple, sensitive, and rapid spectrophotometric method for determining isoniazid, isocarboxazid, and iproniazid phosphate is described. In this method, 2,3-dichloro-5,6-dicyano-p-benzoquinone (a π-acceptor) is used to form charge-transfer complexes with cited drugs (n-donors). The procedure is sensitive enough to permit unit dose assay of the individual drugs in their pharmaceutical formulations. The assay results are in accord with the pharmacopoeial assay results.

scholarly journals Spectrophotometric Determination of Various Drugs Using Chloranilic Acid as Chromogenic Reagent - II

2010 ◽  
Vol 7 (2) ◽  
pp. 624-628 ◽  
Author(s):  
V. Annapurna ◽  
G. Jyothi ◽  
T. Rohini Kumari ◽  
B. B. V. Sailaja
Keyword(s):  
Regression Analysis ◽  
Charge Transfer ◽  
Spectrophotometric Method ◽  
Standard Error ◽  
Redox Reaction ◽  
Charge Transfer Complex ◽  
Molar Absorptivity ◽  
Method Of Least Squares ◽  
Chloranilic Acid

Simple, accurate and reproducible visible spectrophotometric method for the assay of drugs such as pyrilamine and fluvoxamine as maleates was established based on the formation of charge-transfer complex and redox reaction between the corresponding drug and substitutedp-benzoquinone (chloranilic acid). The optical characteristics such as Beer’s law limits, molar absorptivity and Sandell’s sensitivity are reported. 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 drug.

scholarly journals Development and application of spectrophotometric method for quantitative determination of Metronidazole in pure and tablet formulations

2016 ◽  
Vol 2 (1) ◽  
pp. 28 ◽  
Author(s):  
Zeeshan Masood ◽  
Muhammad Tayyab Ansari ◽  
Sharjeel Adnan ◽  
Muhammad Asad ◽  
Muhammad Farooq ◽  
...  
Keyword(s):  
Quantitative Determination ◽  
Spectrophotometric Method ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Dosage Forms ◽  
Nitrite Ion ◽  
Colored Complex ◽  
Accuracy And Precision ◽  
Significant Difference

A rapid, simple and sensitive spectrophotometric method has been developed for the determination of metronidazole in pharmaceutical pure and dosage forms. The method depends on alkaline hydrolysis of metronidazole releases the nitro group as nitrite ion and yielded nitrite ions can be used to give a colored complex that absorbs maximally at 505 nm. Beer’s law is obeyed in the concentration ranges 9-100 mg/ml with molar absorptivity of 1.14 ×103 L mole-1 cm-1. The proposed method is precise, accurate and specific for the quantitative determination of drug in bulk and dosage forms. The results of analysis of commercial formulations and the recovery study of metronidazole suggested that there is no interference from any excipients, which are present in pharmaceutical formulations of metronidazole. Statistical comparison of the results was performed with regard to accuracy and precision using student’s t-test and F-ratio at 95% confidence level. There is no significant difference between the reported and proposed methods with regard to accuracy and precision.

scholarly journals Use of the Charge Transfer Reactions for the Spectrophotometric Determination of Risperidone in Pure and in Dosage Forms

2013 ◽  
Vol 2013 ◽  
pp. 1-6
Author(s):  
Hemavathi Nagaraju Deepakumari ◽  
Hosakere Doddarevanna Revanasiddappa
Keyword(s):  
Charge Transfer ◽  
Pharmaceutical Preparations ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Charge Transfer Complexes ◽  
Chloranilic Acid ◽  
Colored Complex ◽  
Relative Standard ◽  
Complexation Reactions

The aim of study was to develop and validate two simple, sensitive, and extraction-free spectrophotometric methods for the estimation of risperidone in both pure and pharmaceutical preparations. They are based on the charge transfer complexation reactions between risperidone (RSP) as n-electron donor and p-chloranilic acid (p-CA) in method A and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in method B as π-acceptors. In method A, RSP reacts with p-CA in methanol to produce a bright pink-colored chromogen measured at 530 nm whereas, in method B, RSP reacts with DDQ in dichloromethane to form orange-colored complex with a maximum absorption at 460 nm. Beer's law was obeyed in the concentration range of 0–25 and 0–50 μg/mL with molar absorptivity of and L/moL/cm for RSP in methods A and B, respectively. The effects of variables such as reagents, time, and stability of the charge transfer complexes were investigated to optimize the procedures. The proposed methods have been successfully applied to the determination of RSP in pharmaceutical formulations. Results indicate that the methods are accurate, precise, and reproducible (relative standard deviation %).

Sign in / Sign up

Export Citation Format

Share Document