A new, simple, sensitive and fast developed method was used for the determination of methyldopa in pure and pharmaceutical formulations by using continuous flow injection analysis. This method is based on formation a burgundy color complex between methyldopa andammonium ceric (IV) nitrate in aqueous medium using long distance chasing photometer NAG-ADF-300-2. The linear range for calibration graph was 0.05-8.3 mmol/L for cell A and 0.1-8.5 mmol/L for cell B, and LOD 952.8000 ng /200 µL for cell A and 3.3348 µg /200 µL for cell B respectively with correlation coefficient (r) 0.9994 for cell A and 0.9991 for cell B, RSD % was lower than 1 % for n=8. The results were compared with classical method UV-Spectrophotometric at λ max=280 nm and turbidmetric method by using the standard addition method via the use of t-test, at 95% confidence level. In addition to the make use of the advantages of using F-test to predict which of the methods is more precise than other method. The comparison of data explains that long distance chasing photometer (NAG-ADF-300-2) is the choice with excellent extended detection, wide application and more sensitive.
A batch and flow injection (FI) methods with spectrophotometric detection is proposed for determining of two of phenolic drugs: salbutamol sulphate(SLB)and pyridoxine hydrochloride(PYD) in pure and in pharmaceutical formulations. The methods utilized an oxidative-coupling reaction based upon oxidation of 2,4-dinitrophenylhydrazine (DNPH) with sodium periodate, where an electrophilic intermediate (diazonium salt of the reagent) is produced, which couples with either SLB or PYD in the presence of sodium hydroxide yielding a highly colored condensation product. The absorbance is measured after 15min at 525and515 nm for SLB and PYD respectively. Calibration graphs for both batch and FIA methods were linear over the concentration ranges of 1-
... Show MoreA batch and flow injection (FI) spectrophotometric methods are described for the determination of barbituric acid in aqueous and urine samples. The method is based on the oxidative coupling reaction of barbituric acid with 4-aminoantipyrine and potassium iodate to form purple water soluble stable product at λ 510 nm. Good linearity for both methods was obtained ranging from 2 to 60 μg mL−1, 5–100 μg mL−1 for batch and FI techniques, respectively. The limit of detection (signal/noise = 3) of 0.45 μg mL−1 for batch method and 0.48 μg mL−1 for FI analysis was obtained. The proposed methods were applied successfully for the determination of barbituric acid in tap water, river water, and urine samples with good recoveries of 99.92
... Show MoreA newly flow injection-turbidimetric method characterized by it is speed and sensitivity has been developed for the determination of Amiloride in pure and pharmaceutical preparations. It is based on the formation of yellowish white precipitate for the Amiloride-phosphomolybidic acid ion pair in aqueous medium. Turbidity was measured by Ayah 6Sx1-T-1D solar cell CFI analyser via the attenuation of incident light from the surfaces precipitated particles at 0-180. The Chemical and physical parameters were investigated. Linear dynamic range for the attenuation of incident light versus Amiloride concentration was of 0.005-10 mmol.L-1, with the correlation coefficient (r) of 0.9986 , while the percentage linearity (r2%) was 99.71%. The L.O.
... Show MoreA newly flow injection-turbidimetric method characterized by it is speed and sensitivity has been developed for the determination of Amiloride in pure and pharmaceutical preparations. It is based on the formation of yellowish white precipitate for the Amiloride-phosphomolybidic acid ion pair in aqueous medium. Turbidity was measured by Ayah 6Sx1-T-1D solar cell CFI analyser via the attenuation of incident light from the surfaces precipitated particles at 0-180. The Chemical and physical parameters were investigated. Linear dynamic range for the attenuation of incident light versus Amiloride concentration was of 0.005-10 mmol.L-1, with the correlation coefficient (r) of 0.9986 , while the percentage linearity (r2%) was 99.71%. The L.O.
... Show MoreIt is generally accepted that there are two spectrophotometric techniques for quantifying ceftazidime (CFT) in bulk medications and pharmaceutical formulations. The methods are described as simple, sensitive, selective, accurate and efficient techniques. The first method used an alkaline medium to convert ceftazidime to its diazonium salt, which is then combined with the 1-Naphthol (1-NPT) and 2-Naphthol (2-NPT) reagents. The azo dye that was produced brown and red in color with absorption intensities of ƛmax 585 and 545nm respectively. Beer's law was followed in terms of concentration ranging from (3-40) µg .ml-1 For (CFT-1-NPT) and (CFT-2-NPT), the detection limits were 1.0096 and 0.8017 µg.ml-1, respec
... Show MoreA new spectrophotometric flow injection method has been establish for the determintaions of some catecholaminedrugs
A new mode of methodology was adopted in the assay of PM- HCL based on the use of water crystal gel bead made of poly acrylic acid in which the gel beads were left to absorbe persulphate solution that is necessary for the oxidation of PM- HCL in aqua media . The water crystal act as a reserviour for S2O82- . Optimum parameters were studied giving to specify the chemical and physical parameters. Two line manifold was used .The flow rates of 1.5 and 1.2 ml.min-1 was used , 3 gel beads , 120 μL sample volume , a linear dynamic range extend from 0.01- 18 mmol.L-1. A correlation coefficient (r) of 0.9991while the percentage linearity (r2%) of 99.82% with R.S.D% at 8 mmol.L-1 promethazine-HCl is less than 0.5% (ten replicates) and a detection
... Show MoreBased on the diazotization reaction of 4-aminoacetophenone with sodium nitrite in acid medium to form diazonium salt, which was coupled with Methyldopa to form a violet reddish soluble azo dye with maximum absorbance at 560 nm,a batch procedure had been developed for the estamination of Methyldopa. Under optimum experimental parameters affecting on the development and stability of the colored product, Beer´s law obeyed in the range (0.5-45) ?g.ml-1 with a correlation coefficient (0.9979).The proposed method was successfully applied to the determination of Methyldopa in either pure form and in commercial brands of pharmaceuticals, no interference was observed from common excipients in the formulations. The analytical results obtained by app
... Show MoreReservoir characterization plays a crucial role in comprehending the distribution of formation properties and fluids within heterogeneous reservoirs. This knowledge is instrumental in constructing an accurate three-dimensional model of the reservoir, facilitating predictions regarding porosity, permeability, and fluid flow distribution. Among the various methods employed for reservoir characterization, the hydraulic flow unit stands out as a widely adopted approach. By effectively subdividing the reservoir into distinct zones, each characterized by unique petrophysical and geological properties, hydraulic flow units enable comprehensive reservoir analysis. The concept of the flow unit is closely tied to the flow zone indicator, a cr
... Show MoreTwo rapid, simpleand sensitive flow injection methods were developed for the estimation of metronidazole (MRZ) in pharmaceutical formulations. The proposed methods were based on charge transfer reaction between metol (N-methyl-p-aminophenol sulfate) as a π-acceptorand reduced MRZ as an n-donor to produce a blue colored chargetransfer complex. Method A depends on the reaction of reduced MRZ with metol (MT) in the presence of NaIO4 using two lines manifold to form blue colored product exhibiting absorption maxima at 700 nm.While method B depends on charge transfer reaction of reduced MRZ with MT in presence of a solid phase reactorcontainingfixedFePO4 on cellulose acetateusing reverse flow
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