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In this paper, analytical techniques for the determination of ethylenediaminetetraacetic acid (EDTA) and diethylenetriaminepentaacetic acid (DTPA) are reviewed. These compounds, especially EDTA, are used as metal chelating agents in several industries. As they are likely to be poorly degraded in waste water treatment plants, significant amounts of EDTA and DTPA are released into natural waters. The...
Tl(I) and Tl(III) are preconcentrated simultaneously from aqueous solutions by colloid precipitate flotation using two collectors: hydrated iron(III) oxide (Fe2O3·xH2O) and iron(III) tetramethylenedithiocarbamate (Fe(TMDTC)3). After the coprecipitation step and the addition of foaming agents, Tl(I) and Tl(III) were separated from the water by a stream of air bubbles. Various factors affecting Tl(I)...
The vanadium content in chloride rich hydrogeochemical samples has been determined through a modification in the existing standard gallic acid oxidation method which has severe interference problem from halides. The modification incorporates a preliminary fume-drying of the sample aliquot with a mixture of perchloric and sulphuric acids. This ensures total removal of halides and hence their interference...
A method for the simultaneous spectrophotometric determination of the divalent ions of iron, cobalt, nickel and copper based on the formation of their complexes with 1,5-bis(di-2-pyridylmethylene) thiocarbonohydrazide (DPTH) is proposed. The resolution of quaternary mixtures of these metallic ions was accomplished by several chemometric approaches. A comparative study of the results obtained for simultaneous...
Vanadium(V) and iron(III) can be determined simultaneously at pH 2 and 25 o C by a single experiment using their kinetic effect on the oxidation of indigo carmine by bromate which goes through an induction period and then decreases in absorbance, at λ max , 612 nm. The rate of the color-fading of indigo carmine is proportional to the concentration of vanadium and is independent...
A simple and rapid separation method is described for the determination of fluoride in plant samples. Fluoride is separated by distillation in the presence of H 2 SO 4 and H 2 O 2 in a dry air steam. The variables that influence the distillation quantitation were optimized. The fluorides separated were subsequently determined by a spectrophotometric method of the La(III)-F...
FT-Raman spectroscopy based on band intensity and band area measurements, was used for the quantitative determination of diazinon in pesticide formulations. Bands at 554, 604, 631, 1562 and 2971 cm -1 were used for calibration. Spectra were acquired by averaging 100 scans at a resolution of 4 cm -1 . Calibration curves were linear (correlation coefficients, 0.992-0.9992 and...
Praseodymium forms a Pr(LMFX) 3 complex with lomefloxacin. In this paper, the absorption spectra of the complex has been investigated by applying conventional and derivative spectrophotometric methods. It was found that lomefloxacin could form a stable complex with praseodymium in the pH 6.5-8.5 media. The absorption intensity of the complex is 4.5-fold more than PrCl 3 . Using the...
The electrochemical behavior of ceftazidime (CFZ) at four different kinds of electrodes viz. static mercury drop electrode (SMDE), controlled growth mercury electrode (CGME), glassy carbon electrode (GCE) and carbon paste electrode (CPE) has been presented. Optimal operational parameters have been selected for the drug preconcentration and determination in aqueous medium. Down to 2x10 -1...
A new bulk acoustic wave (BAW) sensor modified with a molecularly imprinted polymer (MIP) was fabricated and applied for the determination of pyrimethamine. This sensor exhibited high selectivity and sensitive response to pyrimethamine. Factors such as pH and the amount of coating influencing sensor properties, were investigated in detail and optimized. The calibration curve was linear in the range...
The phosphorus content of some animal protein sources was determined in order to identify the sample with the highest phosphorus content for use as a pilot sample. Varying concentrations of strontium and lanthanum were added to solutions of the ashed pilot sample for the determination of calcium and magnesium using flame atomic absorption spectrophotometry operated on the air-acetylene mode. At least...
A nafion film coated glassy carbon electrode (NFGCE) was employed for the determination of paraquat. Paraquat was accumulated onto NFGCE by the cation-exchange feature of nafion at open circuit potential in basic medium followed by cathodic differential pulse voltammetric (CDPV) determination in a medium containing permanganate ions. The sensitivity for the determination of paraquat was improved through...
Under controlling pH 3, R-(+)- and S-(-)-ofloxacin (OFLX) enantiomers can be well recognized and resolved by the synchronization-1st derivative fluorescence spectroscopic techniques, and the interference from urine blank also can be eliminated. The linear dynamic ranges are 0.36-2.16 (R), 0.36-2.89 and 3.16-31.6 μg/ml (S), respectively, for determining OFLX in urine samples. The limits of detection...
Under ultrasonication, the ginkgo terpene trilactones, ginkgolides and bilobalide, in ginkgo extracts can be selectively dissolved in 10% aqueous NaH 2 PO 4 solution at a temperature of 50-60 o C and separated from the solution by extraction with a mixture of ethyl acetate/tetrahydrofuran in a capped vial. After derivatization, these terpene trilactones can be quantified using...
Isosorbide dinitrate (ISDN) is reduced voltammetrically at gold working electrode surface in aqueous sodium sulfite solution and produces a voltammogram with its peak current proportional to the concentration of ISDN in the range of 1.3-2340 μg ml -1 . Sodium sulfite is used as supporting electrolyte and oxygen removing agent and, therefore, no nitrogen gas purging for elimination of...
The purpose of this study was to develop an accurate and precise analytical procedure for the determination of the content of antimony in coordination compounds of metal(II) hexafluoroantimonates(V) (M(SbF 6 ) 2 compounds, where M=Mg, Ca, Sr or Ba) synthesized in our laboratory. The major problem was to find an appropriate reagent for reductive decomposition of SbF 6- ...
The supramolecular interaction of rubidate (chemically 2,3-naphthalenedicarboxylic acid, 1,4-dihydroxy-diethyl ester) and β-cyclodextrin (β-CD) has been studied by spectrofluorimetry. The influence of temperature on the supramolecular system has also been investigated and the thermodynamic parameters were calculated. The results show that β-CD reacts with rubidate to form a 1:1 host-guest complex...
A sensitive fluorimetric method for the determination of nitrogen oxides (NO x : NO+NO 2 ) in air is described. Nitrogen dioxide (nitrogen monoxide was previously converted to nitrogen dioxide in oxide tubes) was aspirated through a fritted glass bubble at a flow rate of 500 ml min -1 for 120 min and fixed as nitrite, using 0.1 N NaOH as a trapping solution with the empirical...
4-Aminophenol (4AP) is the primary degradation product of paracetamol which is limited at a low level (50 ppm or 0.005% w/w) in the drug substance by the European, United States, British and German Pharmacopoeias, employing a manual colourimetric limit test. The 4AP limit is widened to 1000 ppm or 0.1% w/w for the tablet product monographs, which quote the use of a less sensitive automated HPLC method...
H-point standard addition method (HPSAM) is suggested as a simple and selective method for the determination of semicarbazide and hydrazine. The reduction of Cu 2+ to Cu + by semicarbazide and hydrazine in the presence of neocuproine (Nc) and the subsequent complex formation between Cu + and Nc produced a sensitive spectrophotometric method for indirect determination of...
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