Two simple and sensitive spectrophotometric methods are proposed for the determination of amitriptyline in its pure form and in tablets. The first method is based on the formation of charge- transfer complex between amitriptyline as n-donor and tetracyano-ethylene (TCNE) as πacceptor. The product exhibit absorbance maximum at 470 nm in acetonitrile solvent (pH =9.0 ) . In the second method the absorbance of the ion- pair complex, which is formed between the soughted drug and bromocresol green (BCG), was measured at 415 nm at ( pH=3.5) . In addition to classical univariate optimization, modified simplex method (MSM) was applied in the optimization of the variable affecting the color producing reaction by a geometric simplex in three dimensions of space. Beers, law was obeyed in the concentration ranges 6.0-70 and 8.0-100 µg.ml-1 with molar absorbitivites of 2275 and 1475 l. mol-1 cm-1 for TCNE and BCG methods respectively. The limits of detection of the two methods are 0.043 and 0.034 µg.ml-1 and their Sandells sensitivity values are 0.122 and 0.188 µg.ml-1 respectively.
Spectrophotometric methods were developed for the determination of rantidine-HCl in pharmaceutical tablets. These methods were based on the reaction of DDQ and p-chloranil with rantidine-HCl, resulting in the formation of an orange-red and purple colored products which are quantified spectrophotometrically at 460 and 540nm in DDQ and p-chloranil, respectively. A graph of absorbance versus concentration show that Beer’s law is obeyed in a concentration ranges of 20-160 and (30-120)ïg/ml with molar absorptivities of 2.631 x 103 and 1.052 x 103l .mol-1-cm-1 for DDQ and p-chloranil, respectively. The optimum conditions for color development are described and
... Show More A simple, accurate and precise spectrophotometric method has been proposed for the determination of Mefenamic acid(MA) in dosage forms. Proposed method based on the reaction of cited drug with 1,2-Naphthoquinone-4-Sulfonic sodium (NQS). The optimum experimental condition have been studied. Beer's Law is obeyed in the concentration range 0.5-10.0 µg/mL at 450nm with detection limit of 0.189µg/mL. Effect of pH, reaction time, and volume of NQS on the determination of Mefenamic acid, have been examined. The proposed method has been successfully applied for the determination of Mefenamic acid in pharmaceutical preparations.
A spectrophotometric method has been proposed for the determination of two drugs containing phenol group [phenylephrine hydrochloride (PHP) and salbutamol sulphate (SLB)] in pharmaceutical dosage forms. The method is based on the diazotization reaction of metoclopramide hydrochloride (MCP) and coupling of the diazotized reagent with drugs in alkaline medium to give intense orange colored product (?max at 470 nm for each of PHP and SLB). Variable parameters such as temperature, reaction time and concentration of the reactants have been analyzed and optimized. Under the proposed optimum condition, Beer’s law was obeyed in the concentration range of 1-32 and 1-14 ?g mL-1 for PHP and SLB, respectively. The limit of detection (LOD) and l
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In this study, simple, low cost, precise and speed spectrophotometric methods development for evaluation of sulfacetamide sodium are described. The primary approach contains conversion of sulfacetamide sodium to diazonium salt followed by a reaction with p-cresol as a reagent in the alkaline media. The colored product has an orange colour with absorbance at λmax 450 nm. At the concentration range of (5.0-100 µg.mL-1), the Beer̆ s Low is obeyed with correlation coefficient (R2= 0.9996), limit of detection as 0.2142 µg.mL-1, limit of quantification as 0.707 µg.mL-1 and molar absorptivity as 1488.249 L.mol-1.cm-1. The other approach, cloud point extraction w
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Simple, precise and economic batch and flow injection analysis (FIA)-spectrophotometric methods have been established for simultaneous determination of salbutamol sulfate (SLB) in bulk powder and pharmaceutical forms. Both methods based on diazotization coupling reaction of SLB with another drug compound (sulfadimidine) as a safe and green diazotization agent in alkaline medium. At 444 nm, the maximum absorption of the orange azo-dye product was observed. A thorough investigation of all chemical and physical factors was conducted for batch and FIA procedures to achieve high sensitivity. Under the optimized experimental variables, SLB obeys Beer’s law in the concentration range of 0.25-4 and 10-100 μg/mL with limits of detection of 0.0
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Simple, precise and economic batch and flow injection analysis (FIA)-spectrophotometric methods have been established for simultaneous determination of salbutamol sulfate (SLB) in bulk powder and pharmaceutical forms. Both methods based on diazotization coupling reaction of SLB with another drug compound (sulfadimidine) as a safe and green diazotization agent in alkaline medium. At 444 nm, the maximum absorption of the orange azo-dye product was observed. A thorough investigation of all chemical and physical factors was conducted for batch and FIA procedures to achieve high sensitivity. Under the optimized experimental variables, SLB obeys Beer’s law in the concentration range of 0.25-4 and 10-100 μg/mL with limits of detection o
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In this work, a simple and very sensitive cloud point extraction (CPE) process was developed for the determination of trace amount of metoclopramide hydrochloride (MTH) in pharmaceutical dosage forms. The method is based on the extraction of the azo-dye results from the coupling reaction of diazotized MTH with p-coumaric acid (p-CA) using nonionic surfactant (Triton X114). The extracted azo-dye in the surfactant rich phase was dissolved in ethanol and detected spectrophotometrically at λmax 480 nm. The reaction was studied using both batch and CPE methods (with and without extraction) and a simple comparison between the two methods was performed. The conditions that may be affected by the extraction process and the sensitivity of m
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For aspirin estimated, a molecularly imprinted polymer MIP-ASP electrodes were generated by electro-polymerization process, the electrodes were prepared by combining the template (aspirin) with (vinyl acetate (VA), 1-vinylimidizole (VIZ) as a functional monomer and N, N-methylene bisacrylamide (MBAA) as crosslinkers using benzoyl peroxide (BPO) as an initiator. The efficiency of the membrane electrodes was analyzed by differential pulse voltammetry (DPV). Four electrodes were synthesized using two different plasticizers, di-butyl sebacate (DBS), di-octyl phthalate (DOP) in PVC matrix. Scanning electron microscopy (SEM) was used to describe the generated MIP, studying the electrodes properties, the slope, detection limit, and life
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