Chromatogaphic determination of molar absorptivity of natural prenyloxycinnamic acids in standardless analysis

A sensitive colorimetric determination of fluoride in drinking water has been developed using a polymeric zirconium complex of 5-(2-Carboxyphenylazo)-8-Hydroxyquinoline as fluoride reagents. The method allowed a reliable determination of fluoride in range of (0.0-1.5) mg L-1. The molar absorptivity of the complex formation is 7695 ± 27 L mol-1 cm-1 at 460 nm. The sensitivity, detection limit, quantitation limit, and percentage recovery for 1.0 mg L-1 fluoride for the proposed method were found to be 0.353 ± 0.013 μg mL-1, 0.1 mg L-1, 0.3 mg L-1, and 101.7 ± 4.1, respectively.

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Spectrophotometeric Determination of Trifluoperazine HCL in Pure Forms and Pharmaceutical Preperations

International Journal of Pharmaceutical and Clinical Research ◽

10.25258/ijpcr.v9i5.8593 ◽

2017 ◽

Vol 9 (5) ◽

Author(s):

Mohammad Hamzah Hamzah ◽

Rawa M M Taqi ◽

Muna M. Hasan ◽

Raid J. M. Al-Timimi

Keyword(s):

Standard Method ◽

Limit Of Detection ◽

Molar Absorptivity ◽

Dosage Forms ◽

Oxidizing Agent ◽

Optimum Conditions ◽

Limit Of Quantification ◽

Cerium Ion ◽

Blank Solution

A simple and accurate spectrophotometric method for the determination of Trifluoperazine HCl in pure and dosage forms was developed. The method is based on the reaction between Trifluoperazine HCl and p-chloroaniline in the presence of cerium ion as oxidizing agent which lead to the formation of violate color product that absorbed at a maximum wavelength 570nm while the blank solution was pink. Under the optimum conditions a linear relationship between the intensity and concentration of TRF in the range 4-50μg/ml was obtained . The molar absorptivity 3.74×103 L.mol-1.cm-1 , Limit of detection (2.21μg/ml), while limit of quantification was 7.39μg/ml. The proposed analytical method was compared with standard method using t-test and F-test , the obtained results shows there is no significant differences between proposed method and standard method. Based on that the proposed method can be used as an alternative method for the determination of TRF in pure and dosage forms.

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

International Journal of Drug Delivery Technology ◽

10.25258/ijddt.v9i3.20 ◽

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.

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Molar Absorptivity Values for Aflatoxins and Justification for Their Use as Criteria of Purity of Analytical Standards

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/53.1.96 ◽

1970 ◽

Vol 53 (1) ◽

pp. 96-101 ◽

Cited By ~ 2

Author(s):

J V Rodricks ◽

L Stoloff ◽

W A Pons ◽

J A Robertson ◽

L A Goldblatt

Keyword(s):

Thin Layer ◽

Statistical Study ◽

Molar Absorptivity ◽

Confidence Limits ◽

Components Of Variance ◽

Significant Difference ◽

Single Determination ◽

Comparison Measurements ◽

Analytical Standards

Abstract Measurements of molar absorptivities in methanol were carried out by two laboratories on samples of anatoxins Bi and Gi prepared and purified independently in four laboratories and on samples of aflatoxins B2 and G2 prepared and purified independently in three laboratories. Molar absorptivities of pure aflatoxins Bi, B2, G1, and G2 in benzene-acetonitrile (98 + 2) were determined at two laboratories. With the exception of aflatoxin G2, no significant difference between aflatoxin samples could be demonstrated. Molar absorptivity values and absorbance ratios for each aflatoxin, based on these data, are given. Statistical 95% confidence limits were established for a single determination of molar absorptivity. A statistical study was made of the components of variance which contribute to the accuracy of the determination of molar absorptivity. A comparison of the fluorescence intensities of spots of various aflatoxin preparations, developed on silica gel-coated thin layer plates, with the amount of aflatoxin in each spotting solution as determined by absorbance measurements, demonstrated the validity of using absorbance and fluorescence comparison measurements for aflatoxin quantitation.

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

E-Journal of Chemistry ◽

10.1155/2007/289426 ◽

2007 ◽

Vol 4 (4) ◽

pp. 496-501 ◽

Cited By ~ 3

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.

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Spectrophotometric Determination of Zidovudine in Pharmaceuticals Based on Charge-Transfer Complexation Involving N-Bromosuccinimide, Metol and Sulphanilic Acid as Reagents

E-Journal of Chemistry ◽

10.1155/2007/808130 ◽

2007 ◽

Vol 4 (2) ◽

pp. 173-179 ◽

Cited By ~ 3

Author(s):

K. Basavaiah ◽

U. R. Anil Kumar

Keyword(s):

Limit Of Detection ◽

Pharmaceutical Preparations ◽

Reference Method ◽

Standard Addition ◽

Molar Absorptivity ◽

Sulphanilic Acid ◽

Bulk Drug ◽

Student’S T ◽

Charge Transfer Complexation

A simple spectrophotometric method is proposed for the determination of zidovudine(ZDV) in bulk drug and in pharmaceutical preparations. The method is based on the oxidation of ZDV by a known excess of oxidant N-bromosuccinimide (NBS), in buffer medium of pH 1.5, followed by the estimation of unreacted amount of oxidant with metol and sulphanilic acid. The reacted oxidant corresponds to the amount ZDV. The purple-red reaction product absorbs maximally at 530 nm and Beer’s law is obeyed over a range 5 to 75 μg mL-1. The apparent molar absorptivity is calculated to be 5.1×103L mol-1cm-1, and the corresponding Sandell sensitivity value is 0.052 μg cm-2. The limit of detection and quantification are found to be 0.90 and 2.72, respectively. Intra-day and inter-day precision and accuracy of the developed methods were evaluated as per the current ICH guidelines. The method was successfully applied to the assay of ZDV in tablet/capsule preparations and the results were statistically compared with those of the reference method by applying the Student’s t-test and F-test. No interference was observed from the common tablet/capsule excipients. The accuracy of the method was further ascertained by performing recovery studies via standard-addition method.

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UV-Visible Spectrophotometric Determination of Lambda-Cyhalothrin Insecticide in Vegetables, Soil and Water Samples

Journal of Ravishankar University (Part-B) ◽

10.52228/jrub.2018-31-1-1 ◽

2019 ◽

Vol 31 (1) ◽

pp. 1-9

Author(s):

Deepak Kumar Sahu ◽

Joyce Rai ◽

Chhaya Bhatt ◽

Manish K. Rai ◽

Jyoti Goswami ◽

...

Keyword(s):

Crop Production ◽

Limit Of Detection ◽

Low Cost ◽

Molar Absorptivity ◽

Agricultural Field ◽

Limit Of Quantification ◽

Yellow Colour ◽

Modern Age ◽

Lambda Cyhalothrin

In modern age pesticide is used widely in agriculture. Lambda-cyhalothrin (LCT) is one of the most used pesticides which are used as a insecticide to kill pest, tricks, flies etc in agricultural field and it is also used for crop production. We have developed new method to detect LCT insecticide in agriculture field and reduce its uses. In this method we found the maximum absorbance at 460 nm for yellow colour dye. We also calculated limit of detection and limit of quantification 0.001 mg kg-1 and 0.056 mg kg-1 respectively. Molar absorptivity and Sandell’s sensitivity was also calculated and obtained 1.782 ×107 mol-1 cm-1 and 9.996 ×10-6 µg cm-2 respectively. The obtained yellow colour dye obeyed Beer’s law limit range of 0.5 µg ml -1 to 16 µg ml-1 in 25 ml. This method is less time consuming, selective, simple, sensitive and low cost. Present method is successfully applied in various soil, water and vegetable samples.

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

INDIAN DRUGS ◽

10.53879/id.54.03.10721 ◽

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.

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

Open Chemistry ◽

10.2478/s11532-006-0035-z ◽

2006 ◽

Vol 4 (4) ◽

pp. 708-722 ◽

Cited By ~ 5

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.

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Simple Spectrophotometric Method for Determination of Paroxetine in Tablets Using 1,2-Naphthoquinone-4-Sulphonate as a Chromogenic Reagent

International Journal of Analytical Chemistry ◽

10.1155/2009/237601 ◽

2009 ◽

Vol 2009 ◽

pp. 1-8 ◽

Cited By ~ 2

Author(s):

Ibrahim A. Darwish ◽

Heba H. Abdine ◽

Sawsan M. Amer ◽

Lama I. Al-Rayes

Keyword(s):

Spectrophotometric Method ◽

Correlation Coefficients ◽

Molar Absorptivity ◽

Official Method ◽

Calibration Data ◽

Pharmaceutical Tablets ◽

Relative Standard ◽

Label Claim ◽

Colored Product

Simple and rapid spectrophotometric method has been developed and validated for the determination of paroxetine (PRX) in tablets. The proposed method was based on nucleophilic substitution reaction of PRX with 1,2-naphthoquinone-4-sulphonate (NQS) in an alkaline medium to form an orange-colored product of maximum absorption peak () at 488 nm. The stoichiometry and kinetics of the reaction were studied, and the reaction mechanism was postulated. Under the optimized reaction conditions, Beer's law correlating the absorbance (A) with PRX concentration (C) was obeyed in the range of 1–8 g . The regression equation for the calibration data was: A = 0.0031 + 0.1609 C, with good correlation coefficients (0.9992). The molar absorptivity () was L 1 . The limits of detection and quantitation were 0.3 and 0.8 g , respectively. The precision of the method was satisfactory; the values of relative standard deviations did not exceed 2%. The proposed method was successfully applied to the determination of PRX in its pharmaceutical tablets with good accuracy and precisions; the label claim percentage was %. The results obtained by the proposed method were comparable with those obtained by the official method.

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