A new simple and sensitive spectrophotometric method is described for quantification of Nifedipine (NIF) and their pharmaceutical formulation. The selective method was performed by the reduction of NIF nitro group to yield primary amino group using zinc powder with hydrochloric acid. The produced aromatic amine was submitted to oxidative coupling reaction with pyrocatechol and ammonium ceric nitrate to form orange color product measured spectrophotometrically with maximum absorption at 467nm. The product was determined through flow injection analysis (FIA) system and all the chemical and physical parameters were optimized. The concentration range from 5.0 to 140.0 μg.mL-1 was obeyed Beer’s law with a limit of detection and quantitation 1.48 and 4.96 μg.mL-1 respectively. Agoodprecision,low scattering point of the calibration graph and good accuracyin addition, FIA introduced a good linear range with acceptable sensitivity. High correlation coefficient (0.9996) was found. The proposed method was successfully applied to assay NIF and its pharmaceutical dosage also could be utilized for pharmaceutical routine analysis of the drug.
A new, Simple, sensitive and accurate spectrophotometric methods have been developed for the determination of sulfanilamide (SNA) drug in pure and in synthetic sample. This method based on the reaction of sulfanilamide (SNA) with 1,2-napthoquinone-4-sulphonic acid (NQS) to form N-alkylamono naphthoquinone by replacement of the sulphonate group of the naphthoquinone sulphonic acid by an amino group. The colored chromogen shows absorption maximum at 455 nm. The optimum conditions of condensation reaction forms were investigated by: (1) univariable method, by optimizing the effect of experimental variables; (different bases, reagent concentration, borax concentration and reaction time), (2) central composite design (CCD) including
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Naproxen(NPX) imprinted liquid electrodes of polymers are built using polymerization precipitation. The molecularly imprinted (MIP) and non imprinted (NIP) polymers were synthesized using NPX as a template. In the polymerization precipitation involved, styrene(STY) was used as monomer, N,N-methylenediacrylamide (N,N-MDAM) as a cross-linker and benzoyl peroxide (BPO) as an initiator. The molecularly imprinted membranes and the non-imprinted membranes were prepared using acetophenone(AOPH) and di octylphathalate(DOP)as plasticizers in PVC matrix. The slopes and detection limits of the liquid electrodes ranged from)-18.1,-17.72 (mV/decade and )4.0 x 10-
... Show MoreLiquid membrane electrodes for the determination iron(III) were constructed based on chloramphenicol sodium succinate and iron(III) CPSS-Fe(III) as ion pair complex, with four plasticizers Di-butyl phosphate (DBP); Di-butyl phthalate (DBPH); Di-octyl phthalate (DOP); Tri-butyl phosphate (TBP); in PVC matrix . These electrodes give Nernstian and sub-Nernstian slopes (19.79, 24.60, 16.01 and 13.82mV/decade) and linear ranges from (1x10-5-1x10-2 M, 1x10-5-1x10-2 M, 1x10-6-1x10-2 M and 1x10-5-1x10-2 M) respectively. The best electrode was based on DBP plasticizer which gave a slope 19.79 mV/decade, correlation coefficient 0.9999, detection limit of 9×10-6 M, lifetime 37 day displayed good stability and reproducibility and used to determine
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A dispersive liquid-liquid microextraction combines with UV-V is spectrophotometry for the preconcentration and determination of Mefenamic acid in pharmaceutical preparation was developed and introduced. The proposed method is based on the formation of charge transfer complexation between mefenamic acid and chloranil as an n-electron donor and a p-acceptor, respectively to form a violet chromogen complex measured at 542 nm. The important parameters affecting the efficiency of DLLME were evaluated and optimized. Under the optimum conditions, the calibration graphs of standard and drug, were ranged 0.03-10 µg mL-1. The limits of detection, quantification and Sandell's sensitivity were calculated. Good recoveries of MAF Std. and drug at 0.05,
... Show MoreThis work reports the development of an analytical method for the simultaneous analysis of three fluoroquinolones; ciprofloxacin (CIP), norfloxacin (NOR) and ofloxacin (OFL) in soil matrix. The proposed method was performed by using microwave-assisted extraction (MAE), solid-phase extraction (SPE) for samples purification, and finally the pre-concentrated samples were analyzed by HPLC detector. In this study, various organic solvents were tested to extract the test compounds, and the extraction performance was evaluated by testing various parameters including extraction solvent, solvent volume, extraction time, temperature and number of the extraction cycles. The current method showed a good linearity over the concentration ranging from
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A simple and rapid spectrophotometric method for the determination of sulphite SO3-2 is described. The method is based on the rapid reduction of known amount of chromate CrO4-2 in the presence of sulphite in acidic medium of 2N H2SO4. The amount of excess of chromate was measured after it reactions with 1,5-diphenylcarbazide which finally gives a pink-violet, water soluble and stable complex, which exhibit a maximum absorption at 542 nm. Beer's law was obeyed in the concentration range from 0.004-6.0 µg of sulphite in a final volume of 25 ml with a molar absorbtivity of 4.64×104 l.mol-1.cm-1, Sandal's sensitivity index of 0.001724 ?g .cm-2 and relative standard deviation of ±0.55 - ±0.83 depending on the concentration level. The present
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The Cu(II) was found using a quick and uncomplicated procedure that involved reacting it with a freshly synthesized ligand to create an orange complex that had an absorbance peak of 481.5 nm in an acidic solution. The best conditions for the formation of the complex were studied from the concentration of the ligand, medium, the eff ect of the addition sequence, the eff ect of temperature, and the time of complex formation. The results obtained are scatter plot extending from 0.1–9 ppm and a linear range from 0.1–7 ppm. Relative standard deviation (RSD%) for n = 8 is less than 0.5, recovery % (R%) within acceptable values, correlation coeffi cient (r) equal 0.9986, coeffi cient of determination (r2) equal to 0.9973, and percentage capita
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A spectrophotometric determination of azithromycin was optimized using the simplex model. The approach has been proven to be accurate and sensitive. The analyte has been reacted with bromothymol blue (BTB) to form a colored ion pair which has been extracted in chloroform in a buffer medium of pH=4 of potassium phthalate. The extracted colored product was assayed at 415 nm and exhibited a linear quantification range over (1 - 20) g/ml. The excipients did not exhibit any interferences with the proposed approach for assaying azithromycin in pharmaceutical formulations.
A simple, rapid, accurate and sensitive spectrophotometric method is proposed for the detennination of chlorprQm<tZine -HCl in pwe form and in pharmaceutical formulation. This method is based on the formation. of ion assodation complexes of dmg with either thymol
blue or bromophenol blue in an acidic buffer at pH values 4.17 and
3.68, respectively.
The ion-pair complexes formed exhibit absorption maxima at 41 Onm for both thymol blue and bromophenol blue. These complexes· are quantitatively extracted &n
... Show MoreThis paper describes the development of a simple spectrophotometric determination of bismuth III with 4-(2-pyridylazo) resorcinol (PAR) in aqueous solution in the presence of cetypyridinium chloride surfactant at pH 5 which exhibits maximum absorption at 532 nm. Beer's law is obeyed over the range 5-200 µg/25 mL. i.e. 0.2-8 ppm with a molar absorptivity of 3×104 l.mol-1.cm-1 and Sandell's sensitivity index of 0.0069 µg.cm-2. The method has been applied successfully in the determination of Bi (III) in waters and veterinary preparation.