scholarly journals Spectrofluorimetric and Spectrophotometric Determination of Gliclazide in Pharmaceuticals by Derivatization with 4-Chloro-7-nitrobenzo-2-oxa-1,3-diazole

2003 ◽  
Vol 86 (2) ◽  
pp. 209-214 ◽  
Author(s):  
Nahed El-Enany
Keyword(s):  
Reaction Pathway ◽  
Biological Fluids ◽  
Coupling Reaction ◽  
Pharmaceutical Formulations ◽  
Signal To Noise ◽  
Yellow Fluorescence ◽  
Spectrophotometric Methods ◽  
Experimental Parameters ◽  
Good Agreement

Abstract Accurate, sensitive, and simple spectrophotometric and spectrofluorimetric methods were developed for the determination of gliclazide in pharmaceutical formulations and biological fluids. Both methods are based on a coupling reaction between gliclazide and 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole in borate buffer, pH 7.8, in which a yellow reaction product that can be measured spectrophotometrically at 400 nm was developed. The same product exhibited a yellow fluorescence at 470 nm upon excitation at 400 nm. The absorbance–concentration plot was rectilinear over the range of 2–20 μg/mL with minimum detectability [signal-to-noise (S/N) ratio = 2] of 0.2 μg/mL (6.18 × 10−7 M); the fluorescence–concentration plot was rectilinear over the range of 0.2–2.5 μg/mL with minimum detectability (S/N = 2) of 0.02 μg/mL (6.18 × 10−8M). The different experimental parameters affecting the development and stability of the color were carefully studied and optimized. Both methods were successfully applied to the analysis of commercial tablets. The results were in good agreement with those obtained with the official and reference spectrophotometric methods. A proposal of the reaction pathway was presented.

scholarly journals Spectrofluorometric Determination of Fluvoxamine in Dosage Forms, Spiked Plasma, and Real Human Plasma by Derivatization with Fluorescamine

2007 ◽  
Vol 90 (2) ◽  
pp. 376-383 ◽  
Author(s):  
Nahed El-Enany
Keyword(s):  
Human Plasma ◽  
Reaction Pathway ◽  
Biological Fluids ◽  
Pharmaceutical Formulations ◽  
Dosage Forms ◽  
Spectrofluorometric Determination ◽  
Spiked Plasma ◽  
Experimental Parameters ◽  
Good Agreement

Abstract A sensitive, simple, and selective spectrofluorometric method was developed for the determination of fluvoxamine (FXM) in pharmaceutical formulations and biological fluids. The method is based upon the reaction between the drug and fluorescamine in borate buffer of pH 8.0 to yield a highly fluorescent derivative that is measured at 481 nm after excitation at 383 nm. The different experimental parameters affecting the development and stability of the reaction product were carefully studied and optimized. The method was applied for the determination of the drug over the concentration range of 0.11.1 μg/mL with a detection limit of 0.01 μg/mL (2 10-8 M). The proposed method was successfully applied to the analysis of commercial tablets. The results obtained were in good agreement with those obtained using a reported spectrophotometric method. The method was applied for the determination of FXM in spiked human plasma with recovery (n = 4) of 97.32 1.23%, while that in real human plasma (n = 3) was 90.79 2.73%. A proposal for the reaction pathway is presented.

scholarly journals Micellar Enhanced Spectrofluorometric Determination of Labetalol Through Complexation with Aluminium(III): Application to Dosage Forms and Biological Fluids

2007 ◽  
Vol 90 (4) ◽  
pp. 948-956 ◽  
Author(s):  
Nahed El-Enany
Keyword(s):  
Fluorescence Intensity ◽  
Reaction Pathway ◽  
Biological Fluids ◽  
Sodium Dodecyl ◽  
Dosage Forms ◽  
Spectrofluorometric Determination ◽  
Experimental Parameters ◽  
Fluorescent Products ◽  
Good Agreement

Abstract Two simple, sensitive, and specific spectrofluorometric procedures have been developed for the determination of labetalol (LBT) in pharmaceuticals and biological fluids. LBT was found to react with Al3+ , both in acetate buffer of pH 4.5 (Procedure I) and borate buffer of pH 8.0 (Procedure II), to produce highly fluorescent stable complexes. The fluorescence intensity could be enhanced by the addition of sodium dodecyl sulfate, resulting in 3.5- and 2.7-fold increases in the fluorescence intensity for Procedures I and II, respectively. In both procedures, the fluorescence intensity was measured at 408 nm after excitation at 320 nm. The different experimental parameters affecting the development and stability of the fluorescent products were carefully studied and optimized. The fluorescence intensity-concentration plots were rectilinear over the range of 0.020.1 and 0.010.05 g/mL with a detection limit of 0.003 and 0.001 g/mL for Procedures I and II, respectively. The proposed method was successfully applied to commercial tablets containing LBT. The results were in good agreement with those obtained using a reference spectrofluorometric method. Furthermore, the method was applied for the determination of LBT in spiked human plasma, and the recovery (n = 4) was 93.30 2.62%. A proposal of the reaction pathway was postulated for Procedures I and II, respectively.

scholarly journals Spectrophotometric Methods for the Assay of Pyrilamine Maleate Using Chromogenic Reagents

2010 ◽  
Vol 7 (4) ◽  
pp. 1507-1513 ◽  
Author(s):  
V. Annapurna ◽  
G. Jyothi ◽  
V. Nagalakshmi ◽  
B. B. V. Sailaja
Keyword(s):  
Charge Transfer ◽  
Oxidative Coupling ◽  
Coupling Reaction ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Method Of Least Squares ◽  
Spectrophotometric Methods ◽  
Oxidative Coupling Reaction ◽  
Charge Transfer Complexation

Simple, accurate and reproducible UV spectrophotometric methods were established for the assay of pyrilamine maleate (PYRA) based on the formation of oxidative coupling and precipitation, charge transfer complexation products. Method A includes the oxidative coupling reaction of PYRA with 3-methyl-2-benzathiazolinone hydrazone (MBTH) in presence of Ce(IV). The formation of oxidative coupling product with 4-amino phenazone (4-AP) in presence of K3Fe(CN)6is incorporated in method B. Precipitation/charge transfer complex formation of the PYRA with tannic acid (TA)/Metol-Cr(VI) in method C were proposed. The optical characteristics such as Beers law limits, molar absorptivity and Sandell’s sensitivity for the methods (A-C) are given. 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 system. Determination of pyrilamine in bulk form and in pharmaceutical formulations were also incorporated.

scholarly journals Adaptation of Color Reactions for Spectrophotometric Determination of Pitavastatin Calcium in Bulk Drugs and in Pharmaceutical Formulations

2007 ◽  
Vol 4 (2) ◽  
pp. 272-278 ◽  
Author(s):  
Marothu Vamsi Krishna ◽  
Dannana Gowri Sankar
Keyword(s):  
Cost Effective ◽  
Pharmaceutical Formulations ◽  
Reagent Blank ◽  
Colored Complex ◽  
Spectrophotometric Methods ◽  
Experimental Parameters ◽  
The Mean ◽  
Pitavastatin Calcium ◽  
Color Reactions

Three simple, sensitive and cost effective Spectrophotometric methods are described for the determination of pitavastatin calcium (PST) in bulk drugs and in pharmaceutical formulations. These methods are based on the oxidation of PST by ferric chloride in presence ofo-phenanthroline (Method A) or 2, 2’ bipyridyl (Method B) or potassium ferricyanide (Method C). The colored complex formed was measured at 510, 530 and 755 nm for method A, B and C respectively against the reagent blank prepared in the same manner. The optimum experimental parameters for the color production are selected. Beer’s law is valid with in a concentration range of 4-20 μg mL-1for method A, 7.5-37.5 μg mL-1for method B and 5 -25 μg mL-1for method C. For more accurate results, ringbom optimum concentration ranges are 5-18 μg mL-1for method A , 8.5-35.5 μg mL-1for method B and 6.0-23.0 μg mL-1for method C. The molar absorptivities are 3.55x104, 2.10x104and 3.10x104L mol-1cm-1. Where as sandell sensitivities are 0.024, 0.041 and 0.028 μg cm-22 for method A, B and C respectively. The mean percentage recoveries are 99.95 for method A, 101.35 for method B and 100.33 for method C. The developed methods were applied for the determination of PST in bulk powder and in the pharmaceutical formulations without any interference from tablet excipients.

scholarly journals Batch and Flow-Injection Spectrophotometric Determination of Thymol Using Procaine Hydrochloride as a New Chromogenic Reagent

2012 ◽  
Vol 9 (2) ◽  
pp. 302-310 ◽  
Author(s):  
Baghdad Science Journal
Keyword(s):  
Coupling Reaction ◽  
Water Soluble ◽  
Procaine Hydrochloride ◽  
Spectrophotometric Methods ◽  
Sample Throughput ◽  
Experimental Parameters ◽  
Colored Product ◽  
Mouth Wash ◽  
Versus Concentration

New, simple and sensitive batch and Flow-injecton spectrophotometric methods for the determination of Thymol in pure form and in mouth wash preparations have been proposed in this study. These methods were based on a diazotization and coupling reaction between Thymol and diazotized procaine HCl in alkaline medium to form an intense orange-red water-soluble dye that is stable and has a maximum absorption at 474 nm. A graphs of absorbance versus concentration show that Beer’s law is obeyed over the concentration range of 0.4-4.8 and 4-80 µg.ml-1 of Thymol, with detection limits of 0.072 and 1.807 µg.ml-1 of Thymol for batch and FIA methods respectively. The FIA procedure sample throughput was 80 h-1. All different chemical and physical experimental parameters that affecting on the development and stability of the colored product were carefully studied and the proposed methods were successfully applied to the determination of Thymol in mouth wash preparations.

scholarly journals Kinetic and Conventional Spectrophotometric Determination of Bumadizone in its Tablets via Oxidative Coupling with 3-Methyl-2-Benzothiazolinone Hydrazone

2009 ◽  
Vol 5 (3) ◽  
pp. 839-854
Author(s):  
Mohamed Walash ◽  
Fathalla Belal ◽  
Manar Tolba ◽  
Mohamed Halawa
Keyword(s):  
Oxidative Coupling ◽  
Coupling Reaction ◽  
Comparison Method ◽  
Spectrophotometric Methods ◽  
Oxidative Coupling Reaction ◽  
Bulk Drug ◽  
Kinetic Spectrophotometric ◽  
Chloride Method ◽  
Good Agreement

Two simple, sensitive and accurate spectrophotometric methods have been developed for the determination of bumadizone in bulk drug and its tablets. Both methods based on the oxidative coupling reaction with 3-methyl-2-benzothiazolinone hydrazone hydrochloride (MBTH) and measuring the absorbance of the developed colors by direct or kinetic spectrophotometric method. Upon treatment of a mixture of the chromogenic reagent and drug with cerium (IV) ammonium sulfate (method I) or ferric chloride (method I), a red or violet color was developed immediately or after 30 minutes measurable at 557 nm for method I or II, respectively. The absorbance-concentration plots were rectilinear over the ranges of 1-10 μg/mL (r = 0.9999) for method I and 2-16 μg/mL (r = 0.9998) for method II. The detection limits were  0.15 and 0.27 μg/mL & the quantitation limits were 0.46 and 0.84 μg/mL for methods I and II, respectively. Different experimental parameters affecting the development and stability of the reactions products were studied and optimized. The proposed methods were applied successfully to the determination of bumadizone in its tablets, and the results obtained were in good agreement with those obtained using a comparison  method. 

scholarly journals Optimization and Validation of Quantitative Spectrophotometric Methods for the Determination of Alfuzosin in Pharmaceutical Formulations

2007 ◽  
Vol 4 (3) ◽  
pp. 397-407 ◽  
Author(s):  
M. Vamsi Krishna ◽  
D. Gowri Sankar
Keyword(s):  
Room Temperature ◽  
Pharmaceutical Formulations ◽  
Good Precision ◽  
Spectrophotometric Methods ◽  
Experimental Parameters ◽  
Beer's Law ◽  
Colored Product ◽  
Beer’S Law ◽  
Control Application

Three accurate, simple and precise spectrophotometric methods for the determination of alfuzosin hydrochloride in bulk drugs and tablets are developed. The first method is based on the reaction of alfuzosin with ninhydrin reagent inN, N'-dimethylformamide medium (DMF) producing a colored product which absorbs maximally at 575 nm. Beer’s law is obeyed in the concentration range 12.5-62.5 µg/mL of alfuzosin. The second method is based on the reaction of drug with ascorbic acid in DMF medium resulting in the formation of a colored product, which absorbs maximally at 530 nm. Beer’s law is obeyed in the concentration 10-50 µg/mL of alfuzosin. The third method is based on the reaction of alfuzosin withp-benzoquinone (PBQ) to form a colored product with λmax at 400 nm. The products of the reaction were stable for 2 h at room temperature. The optimum experimental parameters for the reactions have been studied. The validity of the described procedures was assessed. Statistical analysis of the results has been carried out revealing high accuracy and good precision. The proposed methods could be used for the determination of alfuzosin in pharmaceutical formulations. The procedures were rapid, simple and suitable for quality control application.

scholarly journals Application of bromate-bromide mixture as a green brominating agent for the spectrophotometric determination of atenolol in pharmaceuticals

2012 ◽  
Vol 18 (1) ◽  
pp. 43-52 ◽  
Author(s):  
Nagaraj Prashanth ◽  
Kanakapura Basavaiah ◽  
Sameer Abdulrahman ◽  
Nagaraju Rajendraprasad ◽  
Basavaiah Vinay
Keyword(s):  
Reference Method ◽  
Standard Addition ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Spectrophotometric Methods ◽  
Highly Sensitive ◽  
Bromination Reaction ◽  
Excess Iodide ◽  
Good Agreement

Two highly sensitive spectrophotometric methods are proposed for the quantification of atenolol (ATN) in pure drug as well as in pharmaceutical formulations. The methods are based on the bromination reaction of ATN with a known excess of bromate-bromide mixture in acid medium followed by the determination of unreacted bromine. The residual bromine is determined by its reaction with excess iodide and the liberated iodine (I3?) is either measured at 360 nm (method A) or reacted with starch followed by the measurement of the starch-iodine chromogen at 570 nm (method B). Under the optimum conditions, ATN could be assayed in the concentration ranges of 0.5-9.0 and 0.3-6.0?g mL-1 for method A and method B, respectively, with corresponding molar absorptivity values of 2.36?104 and 2.89?104 L/mol.cm. Sandell?s sensitivity values are found to be 0.0113 and 0.0092 ?g/cm2 for method A and method B, respectively. The proposed methods were successfully applied to the analysis of different commercial brands of pharmaceutical formulations and the results obtained by the proposed methods were in good agreement with those obtained using the reference method. The reliability of the methods was further ascertained by recovery studies using standard- addition method.

scholarly journals Novel Spectrophotometric Methods for the Determination of Selegiline Hydrochloride in Bulk and Its Pharmaceutical Preparation

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Kumble Divya ◽  
Badiadka Narayana
Keyword(s):  
Spectrophotometric Method ◽  
Pharmaceutical Preparation ◽  
Coupling Reaction ◽  
Pharmaceutical Formulations ◽  
Molar Absorptivity ◽  
Spectrophotometric Methods ◽  
Colored Product ◽  
Optimum Reaction ◽  
Optimum Reaction Condition

A simple and highly selective spectrophotometric method has been developed for the determination of selegiline hydrochloride in bulk and formulations. Method A is based on the oxidation of 3-methyl-2-benzothiazolinone hydrazone in the presence of ceric ammonium sulphate, followed by its coupling reaction with drug to form a colored product having λmax of 629 nm. Method B is based on the coupling reaction of drug with 4-aminoantipyrine to give a new ligand that reacts with copper(II) to give intense bluish red colored chelate which is measured at 539 nm. Beer’s law is obeyed in the range of 10.00–85.00 μg mL−1 with molar absorptivity of 0.98×104 for method A and 20.00–120.00 μg mL−1 with molar absorptivity of 0.94×104 for method B. The optimum reaction condition and the analytical parameters are evaluated. The results obtained indicate that the methods are free from interference of the ingredients; thus they are successfully applied to pharmaceutical formulations.

scholarly journals Extractive spectrophotometric determination of some α-adrenergic-antagonists in pure forms and in pharmaceutical formulations

2012 ◽  
Vol 18 (2) ◽  
pp. 179-191 ◽  
Author(s):  
Sheikh El ◽  
Nahla Esmail ◽  
Ayman Gouda ◽  
Walid Basset
Keyword(s):  
Pharmaceutical Formulations ◽  
Bromothymol Blue ◽  
Bromocresol Green ◽  
Spectrophotometric Methods ◽  
Basic Nitrogen ◽  
Doxazosin Mesylate ◽  
Adrenergic Antagonists ◽  
Ph Range ◽  
Good Agreement

A simple, rapid, and extractive spectrophotometric methods was developed for the determination of some postsynaptic ?-1 adrenoreceptor antagonist; doxazosin mesylate (DOX), terazosin (TRZ) and alfuzosine HCl (ALF) in pure forms and pharmaceutical formulations. The developed methods are based on the formation of yellow colored chloroform ion-pair complexes between the basic nitrogen of the drugs and dyes, namely; bromocresol green (BCG), bromothymol blue (BTB), methyl orange (MO) and alizarine red S (ARS), in acidic buffer of pH range (3.0-5.0). The formed complexes were extracted with chloroform or dichloromethane and measured at 418, 414, 425 and 426 nm for DOX and at 419, 415, 425 and 428 for TRZ and at 418, 412, 421 and 427 nm for ALF using BCG, BTB, MO and ARS, respectively. The analytical parameters and their effects on the reported systems are investigated. Beer?s law was obeyed in the range 1.0-130 ?g mL?1 with correlation coefficient (n = 6) ? 0.9991. The molar absorpitivity, Sandell sensitivity, detection and quantification limits were also calculated. The composition of the ion associates was found 1:1 by Job?s method. The proposed methods have been applied successfully for the analysis of the studied drugs in pure forms and in pharmaceutical formulations with percentage recoveries ranges from 99.18-100.61. The results of analysis were validated statistically. The results were in good agreement and compared with those obtained with reported methods.

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