scholarly journals Spectrophotometric determination ofβ-blocker drugs by oxidation with bromate–bromide mixture and its analytical application to pharmaceutical preparations

2011 ◽  
Vol 25 (6) ◽  
pp. 303-315 ◽  
Author(s):  
Akram M. El-Didamony ◽  
Eman A. H. Erfan
Keyword(s):  
Indigo Carmine ◽  
Pharmaceutical Preparations ◽  
Reaction Conditions ◽  
Statistical Comparison ◽  
Spectrophotometric Methods ◽  
Significant Difference ◽  
Optimum Reaction ◽  
Comparison Of The Results

Three visible spectrophotometric methods (A–C) were developed for the analysis of someβ-blocker drugs, namely atenolol (ATE) and timolol (TIM) based on their reactivity with bromine, generated in situ by the action of hydrochloric acid on bromate–bromide mixture. The determination of residual bromine is based on its ability to bleach the indigo carmine dye and measuring the absorbance at 610 nm (method A). Methods B and C involve treating the unreacted bromine with a measured excess of iron (II), the remaining iron (II) is complexed with 1,10-phenanthroline (method B) or with 2,2'-bipyridyl (method C) and measuring the increase in absorbance at 510 and 522 nm, respectively. In all the methods, the amount of bromine reacted corresponding to the drug content. Regression analysis of Beer's plot showed good correlation in the concentration ranges of 0.4–16.4, 0.8–10.4 and 0.4–12.8 µg/ml using methods A–C, respectively, for ATE and 14–38, 12–32 and 14–38 µg/ml using methods A–C, respectively, for TIM. The optimum reaction conditions and other analytical parameters are evaluated. No interference was observed from the additives and the applicability of the methods was tested by analyzing the pharmaceutical preparations containing the investigated drugs. Statistical comparison of the results with those of official methods shows excellent agreement and indicates no significant difference in precision.

scholarly journals Kinetic Spectrophotometric Determination of Gemifloxacin Mesylate and Moxifloxacin Hydrochloride in Pharmaceutical Preparations Using 4-Chloro-7-nitrobenzo-2-oxa-1,3-diazole

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Mohammed G. Abdel Wahed ◽  
Ragaa El Sheikh ◽  
Ayman A. Gouda ◽  
Sayed Abou Taleb
Keyword(s):  
Limit Of Detection ◽  
Kinetic Method ◽  
Pharmaceutical Preparations ◽  
Fixed Time ◽  
Spectrophotometric Methods ◽  
Relative Standard ◽  
Significant Difference ◽  
Kinetic Spectrophotometric ◽  
Comparison Of The Results

Simple, sensitive, and accurate kinetic spectrophotometric method was proposed for the determination of gemifloxacin mesylate (GMF) and moxifloxacin hydrochloride (MOX) in pure forms and pharmaceutical preparations (tablets). The method is based on coupling the studied drugs with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl) in the presence of alkaline borate buffer. Spectrophotometric measurement was achieved by recording the absorbance at 466 and 464 nm for GMF and MOX, respectively, after a fixed time of 20 and 15 min on a water bath adjusted at 70 ± 5°C for both drugs. The different experimental parameters affecting the development and stability of the color were carefully studied and optimized. The absorbance-concentration plots were linear over the ranges 0.5–8.0 and 2.0–12 μg mL−1for GMF and MOX, respectively. The limit of detection of the kinetic method was about 0.12 (2.47 × 10−7 M) and 0.36 (8.22 × 10−7 M) μg mL−1for GMF and MOX, respectively. The proposed methods have been applied and validated successfully with percentage relative standard deviation (RSD% ≤ 0.52) as precision and percentage relative error (RE% ≤ 1.33) as accuracy. The robustness of the proposed method was examined with recovery values that were 97.5–100.5 ± 1.3–1.9%. Statistical comparison of the results with the reference spectrophotometric methods shows excellent agreement and indicates no significant difference in accuracy or precision.

scholarly journals Indirect Spectrophotometric Methods for the Determination of Tadalafil

2015 ◽  
Vol 1 (2) ◽  
pp. 11 ◽  
Author(s):  
Safwan Mohammad Fraihat
Keyword(s):  
Oxidation Reaction ◽  
Indigo Carmine ◽  
Pharmaceutical Preparations ◽  
Pharmaceutical Formulations ◽  
Blue Dye ◽  
Reaction Products ◽  
Reaction Conditions ◽  
Factors Affecting ◽  
Spectrophotometric Methods

Two spectrophotometric methods were developed for the determination Tadalafil in pharmaceutical preparations. The methods are based on the oxidation reaction with known excess amount of Ce(IV) and estimation of the unreacted amount using Indigo carmine dye (Method A) and in Methylene blue dye  (Method B). the factors affecting the reaction conditions were studied and the absorbance of absorbance of the oxidation reaction products were monitored at 610 and 600 nm for methods A and B respectively. Beer's law is obeyed in the concentration ranges 11 to 50 and 10 to 55 ppm, the limits of detection and quantification are reported. The proposed method was applied to the determination of the drug in pharmaceutical formulations and the results demonstrated that the method is equally accurate, precise and reproducible as the official methods. The validity of method was established by recovery studies with satisfactory results.

scholarly journals Exploiting of the phenoxazine as first – ever use ligand in rapid spectrophotometric methods for the determination of chromium(VI) in environmental samples

2012 ◽  
Vol 23 (2) ◽  
pp. 180-186 ◽  
Author(s):  
Mansour S. Abdul Galil ◽  
Riyad Ahmed Al Okab
Keyword(s):  
Environmental Samples ◽  
Standard Addition ◽  
Addition Method ◽  
Reaction Conditions ◽  
Spectrophotometric Methods ◽  
Chromium Vi ◽  
Hydrochloric Acid Medium ◽  
Significant Difference ◽  
Optimum Reaction

AbstractTwo new rapid, accurate, sensitive, reproducible and economical spectrophotometric methods are described for the determination of hexavalent chromium in bulk and in environmental samples like, water and soil using two new electrophilic coupling spectrophotometric reagents, 2-amino-2′,5-dichlorobenzophenone (MCB) and 2-amino-5-chloro-2'-fluorobenzophenone (MFB) and first-ever use phenoxazine (PNZ). Both methods are based on the oxidation of (MCB) or (MFB) by chromium(VI) in hydrochloric acid medium and coupling with PNZ to yield red colored, which are stable for about 12 h and have an absorbance maximum 520 nm. Beer’s law is obeyed for chromium(VI) in the concentration ranges 0.15-1.20 μg mL-1 and 0.17-1.41 μg mL- 1 respectively. The optimum reaction conditions and other important analytical parameters were established to maximize sensitivity of these methods. Interference by various non-target ions was also investigated. The performance of these methods was further evaluated by recovery tests applying standard addition method, which indicated that there is no significant difference between the proposed methods and the standard reference spectrophotometric method.

scholarly journals Extractive Spectrophotometric Methods for Determination of Zolmitriptan in Tablets

2007 ◽  
Vol 90 (5) ◽  
pp. 1237-1241 ◽  
Author(s):  
Zeynep Aydogmus ◽  
Ipek Inanli
Keyword(s):  
High Performance ◽  
Correlation Coefficients ◽  
Bromothymol Blue ◽  
Chromatography Method ◽  
Statistical Comparison ◽  
Spectrophotometric Methods ◽  
Accuracy And Precision ◽  
Liquid Chromatography Method ◽  
Comparison Of The Results

Abstract Two simple and sensitive extractive spectrophotometric methods have been developed for determination of zolmitriptan (ZTP) in tablets. These methods are based on the formation of yellow ion-pair complexes between ZTP and tropaeolin OO (TPOO) and bromothymol blue (BTB) in citratephosphate buffer of pH 4.0 and 6.0, respectively. The formed complexes were extracted with dichloromethane and measured at 411.5 and 410 nm for TPOO and BTB, respectively. The best conditions of the reactions were studied and optimized. Beer's law was obeyed in the concentration ranges of 220 and 1.517 g/mL with molar absorptivities of 1.42 104 and 1.60 104 L/mol/cm for the TPOO and BTB methods, respectively. Correlation coefficients were 0.9998 and 0.9999 for TPOO and BTB methods, respectively. Limits of detection of the TPOO and BTB methods were 0.341 and 0.344 g/mL, respectively, and the limits of quantitation were 1.034 and 1.051 g/mL, respectively. Sandell's sensitivity and stability constant were also calculated. The proposed methods have been applied successfully for the analysis of the drug in its dosage forms. No interference was observed from excipients present in tablets. Statistical comparison of the results with those obtained by a high-performance liquid chromatography method showed excellent agreement and indicated no significant differences in accuracy and precision.

Spectrofluorimetric Determination of Some Water-Soluble Vitamins

2011 ◽  
Vol 94 (6) ◽  
pp. 1758-1769 ◽  
Author(s):  
Abdel-Maaboud I Mohamed ◽  
Horria A Mohamed ◽  
Niveen M Abdel-Latif ◽  
Marwa R Mohamed
Keyword(s):  
Water Soluble ◽  
Good Precision ◽  
Linear Calibration ◽  
Reaction Conditions ◽  
Pharmaceutical Dosage Forms ◽  
Accuracy And Precision ◽  
Significant Difference ◽  
Spectrofluorimetric Determination ◽  
Comparison Of The Results

Abstract Two simple and sensitive spectrofluorimetric methods were developed for determination of three water-soluble vitamins (B1, B2, and B6) in mixtures in the presence of cyanocobalamin. The first one was for thiamine determination, which depends on the oxidation of thiamine HCl to thiochrome by iodine in an alkaline medium. The method was applied accurately to determine thiamine in binary, ternary, and quaternary mixtures with pyridoxine HCl, riboflavin, and cyanocobalamin without interference. In the second method, riboflavin and pyridoxine HCl were determined fluorimetrically in acetate buffer, pH 6. The three water-soluble vitamins (B1, B2, and B6) were determined spectrofluorimetrically in binary, ternary, and quaternary mixtures in the presence of cyanocobalamin. All variables were studied in order to optimize the reaction conditions. Linear relationship was obeyed for all studied vitamins by the proposed methods at their corresponding λexc or λem. The linear calibration curves were obtained from 10 to 500 ng/mL; the correlation ranged from 0.9991 to 0.9999. The suggested procedures were applied to the analysis of the investigated vitamins in their laboratory-prepared mixtures and pharmaceutical dosage forms from different manufacturers. The RSD range was 0.46–1.02%, which indicates good precision. No interference was observed from common pharmaceutical additives. Good recoveries (97.6 ± 0.7–101.2 ± 0.8%) were obtained. Statistical comparison of the results with reported methods shows excellent agreement and indicates no significant difference in accuracy and precision.

scholarly journals Spectrophotometric Determination of Gemifloxacin Mesylate, Moxifloxacin Hydrochloride, and Enrofloxacin in Pharmaceutical Formulations Using Acid Dyes

2014 ◽  
Vol 2014 ◽  
pp. 1-16 ◽  
Author(s):  
Ayman A. Gouda ◽  
Alaa S. Amin ◽  
Ragaa El-Sheikh ◽  
Amira G. Yousef
Keyword(s):  
Pharmaceutical Formulations ◽  
Bromothymol Blue ◽  
Bromocresol Green ◽  
Bromophenol Blue ◽  
Bromocresol Purple ◽  
Acid Dyes ◽  
Spectrophotometric Methods ◽  
Significant Difference ◽  
Comparison Of The Results

Simple, rapid, and extractive spectrophotometric methods were developed for the determination of some fluoroquinolones antibiotics: gemifloxacin mesylate (GMF), moxifloxacin hydrochloride (MXF), and enrofloxacin (ENF) in pure forms and pharmaceutical formulations. These methods are based on the formation of ion-pair complexes between the basic drugs and acid dyes, namely, bromocresol green (BCG), bromocresol purple (BCP), bromophenol blue (BPB), bromothymol blue (BTB), and methyl orange (MO) in acidic buffer solutions. The formed complexes were extracted with chloroform and measured at 420, 408, 416, 415, and 422 nm for BCG, BCP, BPB, BTB, and MO, respectively, for GMF; at 410, 415, 416, and 420 nm for BCP, BTB, BPB, and MO, respectively, for MXF; and at 419 and 414 nm for BCG and BTB, respectively, in case of ENF. The analytical parameters and their effects are investigated. Beer’s law was obeyed in the ranges 1.0–30, 1.0–20, and 2.0–24 μg mL−1for GMF, MXF, and ENF, respectively. The proposed methods have been applied successfully for the analysis of the studied drugs in pure forms and pharmaceutical formulations. Statistical comparison of the results with the reference methods showed excellent agreement and indicated no significant difference in accuracy and precision.

scholarly journals Development and application of a portable instrument for drugs analysis in pharmaceutical preparations

2015 ◽  
Vol 51 (3) ◽  
pp. 699-708
Author(s):  
Paulo Roberto da Silva Ribeiro ◽  
Helena Redigolo Pezza ◽  
Leonardo Pezza ◽  
Liliane Spazzapam Lima ◽  
Matthieu Tubino
Keyword(s):  
Low Cost ◽  
Pharmaceutical Preparations ◽  
Pharmaceutical Products ◽  
Ammonium Molybdate ◽  
Quantitative Studies ◽  
Significant Difference ◽  
Drugs Analysis ◽  
And Performance

This article describes the application and performance of an inexpensive, simple and portable device for colorimetric quantitative determination of drugs in pharmaceutical preparations. The sensor is a light detector resistor (LDR) incorporated into a black PTFE cell and coupled to a low-cost multimeter (Ohmmeter). Quantitative studies were performed with captopril/p-chloranil/H2O2 and methyldopa/ammonium molybdate systems. Calibration curves were obtained by plotting the electrical resistance of the LDR against the concentration of the colored species in the ranges 1.84 × 10-4 to 1.29 × 10-3mol L-1 and 5.04 × 10-4 to 2.52 × 10-3 mol L-1 for captopril/p-chloranil/H2O2 and methyldopa/ammonium molybdate systems, respectively, exhibiting good coefficients of determination. Statistical analysis of the results obtained showed no significant difference between the proposed methodologies and the official reported methods, as evidenced by the t-test and variance ratio at a 95% confidence level. The results of this study demonstrate the applicability of the instrument for simple, accurate, precise, fast,in situ and low-cost colorimetric analysis of drugs in pharmaceutical products.

scholarly journals Spectrophotometric Determination of Antidepressant Drug Duloxetine in Pharmaceutical Preparations using π-Acceptors

2012 ◽  
Vol 9 (1) ◽  
pp. 323-329 ◽  
Author(s):  
Sidika Ertürk Toker ◽  
Armagan Önal
Keyword(s):  
Spectrophotometric Determination ◽  
Electron Donor ◽  
Pharmaceutical Analysis ◽  
Antidepressant Drug ◽  
Pharmaceutical Preparations ◽  
Reaction Conditions ◽  
Colored Complex ◽  
Complex Species ◽  
Spectrophotometric Methods

In this study, two simple and accurate spectrophotometric methods were presented for the determination of duloxetine hydrochloride (DLX) in pharmaceutical preparations. The methods were based on the reaction of DLX asn-electron donor with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) as π-acceptors to give highly colored complex species. The colored products were quantitated spectro-photometrically at 477 and 841 for DDQ, TCNQ, respectively. All variables were studied in order to optimize the reaction conditions. Beer's law was obeyed in the concentration ranges 10.0-50.0 and 15-60 μg mL−1for DDQ and TCNQ method, respectively. The proposed methods have been successfully applied to the pharmaceutical analysis without any interference from excipients. The suggested procedures could be used for the determination of DLX in pharmaceutical preparations being sensitive, simple and selective.

scholarly journals Of bromination reaction for the spectrophotometric assay of domperidone in pharmaceuticals

2011 ◽  
Vol 17 (1) ◽  
pp. 81-89 ◽  
Author(s):  
Zenita Devi ◽  
K. Basavaiah ◽  
K.B. Vinay
Keyword(s):  
Limit Of Detection ◽  
Pharmaceutical Preparations ◽  
Reference Method ◽  
Standard Addition ◽  
Limit Of Quantification ◽  
Fixed Amount ◽  
Spectrophotometric Methods ◽  
Significant Difference ◽  
Bulk Drug

Three simple and sensitive spectrophotometric methods are described for the determination of domperidone (DOM) in bulk drug and in dosage forms using bromate-bromide mixture as brominating agent in acid medium and three dyes, meta-cresol purple (MCP), amaranth (AMR) and erioglaucine (EGC). The methods involve the addition of a known excess of bromate-bromide mixture to an acidified solution of DOM followed by the determination of the residual bromine by reacting with a fixed amount of either MCP dye and measuring the absorbance at 530 nm (method A) or AMR dye and measuring the absorbance at 520 nm (method B) or EGC dye and measuring the absorbance at 630 nm (method C). Beer?s law is obeyed over the concentration ranges, 0.63 - 10.0, 0.25-4.0 and 0.13-2.0 ?g mL-1 for method A, method B and method C, respectively. The apparent molar absorptivities are calculated to be 3.751 ? 104, 6.604 ? 104 and 1.987 ? 105 L mol-1cm-1 for method A, method B and method C, respectively and the corresponding sandell sensitivity values are 0.011, 0.006 and 0.002 ?g cm-2. The limit of detection and the limit of quantification are also reported for all the three methods. No interference was observed from common additives found in pharmaceutical preparations. Statistical comparisons of the results with those of the reference method showed an excellent agreement, and indicated no significant difference in accuracy and precision. The accuracy and reliability of the methods were further ascertained by performing recovery tests via standard-addition technique.

scholarly journals Spectrophotometric Method for Determination of Five 1,4-Dihydropyridine Drugs Using N-Bromosuccinimide and Indigo Carmine Dye

2013 ◽  
Vol 2013 ◽  
pp. 1-7
Author(s):  
Mohamed A. El Hamd ◽  
Sayed M. Derayea ◽  
Osama H. Abdelmageed ◽  
Hassan F. Askal
Keyword(s):  
Spectrophotometric Method ◽  
Indigo Carmine ◽  
Correlation Coefficients ◽  
Dosage Forms ◽  
Variance Ratio ◽  
Statistical Comparison ◽  
Significant Difference ◽  
Beer’S Law ◽  
Indigo Carmine Dye

Indirect spectrophotometric method is described for quantification of five of 1,4-dihydropyridine (1,4-DHP) drugs using N-bromosuccinimide (NBS) with the aid of indigo carmine (INC) dye. The method is based on addition of known excess of NBS to an acidified solution of 1,4-DHP drugs and determining the residual of NBS through its ability to bleach the colour of the used dye; the amount of NBS that reacted corresponded to the amount of drugs. Beer’s law is obeyed in the concentration range 1.25–13.00 μg/mL. Good correlation coefficients (0.998-0.999) were found between the absorbance values and the corresponding concentrations. Limits of detections ranged from 0.141 to 0.500 μg/mL. The proposed method was successfully applied to the analysis of dosage forms; percent of recoveries ranged from 97.31 to 99.46% without interference from any common excipients. The statistical comparison by Student’s t-test and variance ratio F-test showed no significant difference between the proposed and official or reported methods.

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