摘要:

The synthesis, spectral characteristics and analytical applications of anisaldehyde-4-phenyl-3-thiosemicarbazone (APT) are described. A simple, rapid, selective and sensitive spectrophotometric method for the determination of platinum was developed based on the colour reaction between platinum (IV) and anisaldehyde-4-phenyl-3-thio-semicarbazone (APT) in the pH range 1.7 - 3.0. The yellow coloured species has an absorption maximum at 360 nm. The complexation is complete within 1 min. A five-fold excess of the reagent is required for complete complex formation. Beer's law is obeyed over the concentration range 0.1 -20 ppm of Pt(IV). The mtilar absorptivity and Sandell's sensitivity are 1.58 × 104l. mol−1cm−1and 0.0123 ug of Pt(IV) cm−2, respectively. The effects of pH, time concentration of reagent, order of addition of reagents and the interference from various ions were investigated. The method has been employed for the determination of platinum in synthetic mixtures whose composition correspond to some alloys.

ISSN:0003-2719    

DOI:10.1080/00032718708064585

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The influence of nitric, hydrochloric and sulfuric acids on the measurement of mercury by cold vapor atomic absorption spectrometry has been investigated. Small pre-reduction peaks associated with the instability of mercury were observed in solutions containing ≤ 12.5, < 2 and ≥ 12.5% v/v of each acid, respectively. Mercury was found to be most stable in ≥, 2% v/v hydrochloric acid and the measured absorbance was not greatly influenced by varying concentration of the acid. The mercury absorbance measurements were more sensitive in solutions containing ≤ 6.3% v/v hydrochloric acid than in similar concentrations of nitric and sulfuric acids. The use of the three acids as a digestion mixture result in serious interference from nitrogen oxides. The interferant was removed by use of expelling agents such as urea and sulfamic acid or overcome by use of excess stannous chloride, prior to the reduction of mercury(II) ions. The determination of mercury in NBS albacore tuna using both of these approaches to overcome the interference problem proved to be successful.

ISSN:0003-2719    

DOI:10.1080/00032718708064586

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Eriochrome cyanine R(chrome azurol S) is used as a color reagent to determine Sc in the presence of phosphatidyl choline, σ = 3.7 × 104(4.5 × 104). This method has been connected to extraction separation to determine Sc in the presence of rare earth elements, and good results have been obtained.

ISSN:0003-2719    

DOI:10.1080/00032718708064587

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Nine new hydroxamic acids in conjunction with four pyridylazo reagents were explored for extractive separation and spectrophotometric determination of palladium in environmental samples. It was found that maximum sensitivity and selectivity was achieved by employing N-p-methoxyphenyl-2-furylacrylohydroxamic acid (MFHA) and 5-(diethylamino)-2-(2-pyridylazo) phenol (DEPAP). Palladium was first selectively extracted with MFHA in isoamyl alcohol at pH 2.7-3.5 and the extract was equilibrated with a mixture of 5 M HCl and 10− 3M solution of DEPAP in ethanol. The resulting intensely green ternary complex was measured at 560 nm (σ 5.1 × 104l mole−1cm−1). The extraction system is suitable for enrichment of palladium over 15 times without loss in recovery and enables determination of palladium at levels as low as 10−4ppm (0.1 ppb). The method tolerates the presence of a large number of diverse ions normally associated with palladium, including platinum metals, and was employed for the determination of palladium in standard catalysts, biological materials, and freshwaters.

ISSN:0003-2719    

DOI:10.1080/00032718708064588

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Reversed-phase paper chromatographic separations of As(III), Sb(III) and Bi(III) have been camed out on Whatman No 1 filter paper lmpregnated with tnphenylphosphine oxide as stationary phase and using organic complexmg agents such as sodium acetate, sodium succinate and sodium malonate solutions as active mobile phases. Results for the separation of binary and ternary mixtures are reported and the method has been successfully applied to the separation and detection of these elements present in real samples and at ppm level concentration.

ISSN:0003-2719    

DOI:10.1080/00032718708064589

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

The UV spectrum and polarographic behavior of Cu(II)/IpA complex was investigated, in an aqueous solution of Cu(II)/IpA complex, in Britton Robinson buffer solution at a pH from 5.0 to 8.0. At a low concentration of Cu(II)/IpA complex, maximum absorbance was shown to be 532 nm.

ISSN:0003-2719    

DOI:10.1080/00032718708064590

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A sensitive and specific method for the quantitative determination of the new drug, almitrine bismesylate, was developed based on the procedure reported by Baune et al. The method depends on initial extraction of drug from plasma with cyclohexane followed by separation from acidic constituents by a base wash. Final separation and quantitation of almitrine was achieved by GLC with NPD detection using the dtmethyl derivative (S-2082) as internal standard. The method was shown to be specific for almitrfne and for internal standard by a parallel run using GC/MS and anaiysis of the M.S. species. The procedure was linear from 25 to 175 ng/ml. Assays were routinely performed with 1 ml of plasma though the analysis could be performed with 0.5 ml. The method is rugged, having been run by at least three analysts over a span of more than 5000 samples, and efficient, allowing 60 samples per day throughput on a routine basis.

ISSN:0003-2719    

DOI:10.1080/00032718708064591

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Glutaminase and glutamate oxidase were immobillzed into a gelatin support fixed on a pO2sensor. The overall activity (02consumption) was correlated to glutamine concentrations range from 0.2 to 2mM. The sample oxygen content dependence of the signal was minimized by the support properties. Measuring time for each sample was 2 minutes including response data treatment and rinsing steps. On repeated use, the electrode signal for 0.5mM was stable for 300 assays at least. This technique has been applied in different mammalian cell cultures.

ISSN:0003-2719    

DOI:10.1080/00032718708064592

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

A sensitive sandwich enzyme immunoassay for human inter-leukin-2 (hIL-2) using monoclonal antibody IS described. A monoclonai anti-hIL-2 IgG-coated poiystyrene ball was incubated with hIL-2 and subsequently with affinity-purified rabbit anti-hIL-2 Fab'-horseradish peroxidase conjugate. Peroxidase activity bound to the polystyrene ball was assayed by fluorimetry using 3-(4-hydroxyphenyl)propionic acid as a substrate. There was no cross-reaction with interleukins 1α and 1bT, epidermal growth factor, insulin and other protein hormones. The detection limit of hIL-2 was 3 pg/tube or 30 ng/1 using 0.1 ml of cuiture supernatant. When peripheral blood mononuclear cells from healthy subjects aged 22-62 yr were cultured in the absence and presence of phytohemagglutinin P for 48 h, hIL-2 levels in the culture supernatants were <0.03-0.10 μg/1 and 0.18-3.7 μg/1, respectively.

ISSN:0003-2719    

DOI:10.1080/00032718708064593

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor

摘要:

Ethanol was determined by reaction with NAD in the presence of alcohol dehydrogenase in a continuous flow system. NADH produced was allowed to react with hexacyanoferrate (III) in the presence of diapharase. The concentration of the produced hexacyanoferrate (II) was monitored biamperometrically using open tubular carbon electrodes. A level of 1.5 × 102mg/100 ml ethanol was detected, with an average precision of 4% relative standard deviation. The ethanol level in blood samples was determined, obtaining a 0.08 correlation coefficient with gas chromatography results.

ISSN:0003-2719    

DOI:10.1080/00032718708064594

出版商:Taylor & Francis Group    

年代:1987

数据来源: Taylor