A new simple sensitive and selective spectrophotometric method has been
developed for the analysis of vanadium(V) in three randomly chosen samples from
river water at different locations by continuous flow injection analysis. The method
based on the oxidation of pyrogallol by vanadium(V) in acidic solution to form color
species and the same species was determined using homemade Ayah 6SX1-T-2D
solar cell analyser . Chemical and physical parameters were investigated using the
high intensity of snow white light emitted diode as a source. The linear dynamic
range for the instrument response versus vanadium(V) concentration was 1-200
mg.L-1 with correlation coefficient r = 0.9920. The limit of detection (S/N=3) was 70
ng/ sample from the step wise dilution for the minimum concentration in the linear
dynamic range of the calibration graph with RSD % of lower than 1% at 90 mg.L-1
(n=5) concentration of vanadium(V). The method was applied successfully for the
determination of vanadium (V) in three river samples. A comparison was made
between: both of the proposed methods and classical method (UV-Vis
spectrophotometry at wave length 427 nm) using the standard additions method via
the use of paired t-test. It was noticed that there was no significant difference
between two methods at 95 % confidence level
A newly developed analytical method characterized by its speed and sensitivity for the determination of metformin-HCl via the formation of complex for metformin-HCl-OH--copper(II) ion from the gel bead system by continuous flow injection analysis. The method is based on the imbedded copper(II) ion in the gel bead structure can be used in the reaction for the formation of red –magneta colour complex(λmax. =530nm) formed by direct reaction of the drug with the released copper (II) ion from the gel bead in alkaline medium. Linear dynamic range for the absorbance versus metformin concentration was 0.001-1 mmol.L-1 while C.O.D was (r2% =95.33%) . The L.O.Q was 0.868mmol.L-1.L.O.D (S/N=3)=0.5μmol.L-1 from the step wise dilution for the min
... Show MoreAn indirectly method is used to determine hydrogen peroxide. The method based on oxidation of chromium (III) ion by hydrogen peroxide in basic medium to form chromate ion which react with barium (II) ion to produce a yellow precipitate (BaCrO4). Under the optimum established conditions, the linear range of 0.50-25.00 mmol L-1 along with correlation coefficient (r) of 0.9992, Limit of detection (LOD) 0.68 μg / 100 μL, precision expressed as relative standard deviation for six replication measurements at 5.0 mmol.L-1 H2O2 of less than 2% were obtained for hydrogen peroxide. The developed method was successfully applied for the estimation of H2O2 in three pharmaceuticals preparation of different companies using continuous flow injection o
... Show MoreNew, 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 e
... Show MoreChromatographic and spectrophotometric methods for the estimation of mebendazole in
pharmaceutical products were developed. The flow injection method was based on the oxidation of
mebendazole by a known excess of sodium hypochlorite at pH=9.5. The excess sodium hypochlorite is then
reacted with chloranilic acid (CAA) to bleach out its color. The absorbance of the excess CAA was recorded
at 530 nm. The method is fast, simple, selective, and sensitive. The chromatographic method was carried out
on a Varian C18 column. The mobile phase was a mixture of acetonitrile (ACN), methanol (MeOH), water
and triethylamine (TEA), (56% ACN, 20% MeOH, 23.5% H2O, 0.5% TEA, v/v), adjusted to pH = 3.0 with
1.0 M hy
A 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 new spectrophotometric flow injection method has been establish for the determintaions of some catecholaminedrugs
It 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 MoreSimple and sensitive batch and Flow-injection spectrophotometric methods for the determination of Procaine HCl in pure form and in injections were proposed. These methods were based on a diazotization reaction of procaine HCl with sodium nitrite and hydrochloric acid to form diazonium salt, which is coupled with chromatropic acid in alkaline medium to form an intense pink water-soluble dye that is stable and has a maximum absorption at 508 nm. A graphs of absorbance versus concentration show that Beer’s law is obeyed over the concentration range of 1-40 and 5-400 µg.ml-1 of Procaine HCl, with detection limits of 0.874 and 3.75 µg.ml-1 of Procaine HCl for batch and FIA methods respectively. The FIA average sample throughput was 70 h-1. A
... Show MoreDerivative spectrophotometry is one of the analytical chemistry techniques used
in the analysis and determination of chemicals and pharmaceuticals. This method is
characterized by simplicity, sensitivity and speed. Derivative of Spectra conducted
in several ways, including optical, electronic and mathematical. This operation
usually be done within spectrophotometer. The paper is based on form of a new
program. The program construction is written in Visual Basic language within
Microsoft Excel. The program is able to transform the first, second, third and fourth
derivatives of data and the return of these derivatives to zero order (normal plot).
The program was applied on experimental (trial) and reals values of su