Method For Determination Of Nickel Research Articles

Development a simple and sensitive method for determination low trace of nickel by local surface plasmon resonance of citrate capped silver nanoparticles

Nickel is a toxic transition metal which can create serious problems in health of humans and wildlife. Thus determination of nickel in environmental samples like waters is important and inevitable. In this research a simple and sensitive method for determination of nickel in water was described based on aggregation of citrate capped silver nanoparticles. Silver nanoparticles were prepared by reduction of silver nitrate with sodium borohydride. Cefixime was as chelating agent in the assay and when nickel was added to the mixture of citrate capped silver nanoparticles and cefixime, color of citrate capped silver nanoparticles changed from light yellow to red that depend on Ni2+ concentration. As a result of aggregation, local surface plasmon resonance (LSPR) band of silver nanoparticles around 395 nm decreased and a new peak appeared in 550 nm. Control experiments with 10 other ions carried out and did not a distinct change in color or spectrum. Under optimized conditions, linear relationship between Ni2+ concentrations and the absorbance ratio of A550/A395 and limit of detection were found in the range of 2.70 µmol L-1 to 17.10 µmol L-1 and 0.80 µmol L-1, respectively. The method was applied in tap and well waters that indicate the colorimetric method has acceptable accuracy and good stability.

Development of multivariate calibration method for simultaneous determination of nickel, lead and zinc in tap water

Conventional spectrophotometric methods for simultaneous determination of nickel, lead and zinc in forms of complexes with a reagent is not feasible due to the overlap of their absorption spectra. A multivariate calibration method was used to overcome this problem. In this study, the calibration model was constructed based on absorption spectra of 30 mixture standards in the range from 490 to 600 nm. Factors influencing experimental results such as amount of reagents, pH, and color development time were optimized. The standard calibration ranges for determination of nickel, lead and zinc were found at 0.5-5 ppm. The method was applied for determination of these ions in tap water samples at ppm level, with recoveries (and RSD) of nickel, lead and zinc were 103.3 % (3.0 %), 74.9 % (11.5 %) and 104.6 % (4.6 %), respectively.

A rapid solid sampling method for determination of nickel and copper along human hair by ETAAS

A procedure for copper and nickel determination in scalp hair by solid sampling electrothermal atomic absorption spectrometric method was described. The hair samples (0.02 to 0.4 mg) were inserted directly on the platforms of solid sampling autosampler. The effects of pyrolysis temperature, atomization temperature, the amount of sample as well as addition of a modifier (Pd/Mg) and/or auxiliary digesting agents (hydrogen peroxide and nitric acid) and/or a surfactant (Triton X-100) on the determination of copper and nickel by solid sampling atomic absorption spectrometry were investigated. After optimization of parameters, the average recoveries of copper in two different certified reference hair samples were 105.7 and 97.6%. The recoveries of nickel in the both certified reference hair samples were in 95.2 and 96.4%. The limits of detection (3σ, N = 10) for copper and nickel were 22 ng/g and 35 ng/g, respectively. Heterogenous distribution of analyte in microscale for segmental analysis could be determined which is important to know that analyte quantity and time of poisoning of a person was exposed. For this purpose, 0.5 cm of pieces were cut along one or a few close strands and analyzed by solid sampling. This process could not be performed by wet-digestion method because 50 mg of sample is needed each time. Finally, the method was applied for the determination of copper and nickel concentrations in the hairs of different persons.

<b>Extraction-spectrophotometric determination of nickel at microgram level in water and wastewater using 2-[(2-mercaptophenylimino)methyl]phenol</b>

An extraction-spectrophotometric method for determination of nickel at sub ppm level using 2-[(2-mercaptophenylimino)methyl]phenol (MPMP) as the new extractant is described. The reagent reacts with nickel(II) at pH > 10 and form a 1:2 brown complex, which is extracted into chloroform. The complex has a maximum absorption at 421 nm with the molar absorptivity of 2.41 × 10 5 M -1 cm -1 . Beer’s law is obeyed over the range of 0.011-0.30 µg mL -1 . The Sandell’s sensitivity for 0.001 absorbance unit is 5.34 × 10 -4 µg cm -2 . The relative standard deviation at 0.018 µg mL -1 is 1.1 % (n = 8). The procedure was successfully applied to determination of nickel in wastewater and standard alloy and the accuracy was determined by recovery experiment, independent analysis by furnace-AAS, and analysis of a certified reference martial. KEY WORDS: Ni determination, Liquid-liquid extraction, Schiff bases, Spectrophotometry Bull. Chem. Soc. Ethiop. 2008 , 22(3), 323-329.

Simultaneous Determination of Nickel and Cadmium by Adsorptive Stripping Voltammetry

AbstractA sensitive and fast method for the simultaneous determination of trace amounts of nickel and cadmium in real samples has been described using differential pulse adsorptive stripping voltammetry (DPASV) by adsorptive accumulation of the N,N′‐bis(salicylaldehydo)4‐carboxyphenylenediamine (BSCPDA)–complex on the hanging mercury drop electrode (HMDE). As supporting electrolyte 0.02 mol L−1 ammonia buffers containing ligand has been used. Optimal analytical conditions were found to be: BSCPDA concentration of 42 μM, pH 9.6 and adsorption potential at −50 mV versus Ag/AgCl. With an accumulation time of 20 s, the peaks current are proportional to the concentration of nickel and cadmium over the 1–180, and 0.5–200 ng mL−1 with detection limits of 0.06 and 0.03 ng mL−1 respectively. The sensitivity of method for determination of nickel and cadmium were obtained 0.54 and 0.98 nA mL ng−1, respectively. The procedure was applied to simultaneous determination of nickel and cadmium in some real and synthetic artificial samples with satisfactory results.

Determination of nickel and cobalt by constant current potentiometry

The performance of a constant current potentiometric method for the simultaneous determination of nickel and cobalt as their DMG complexes in a batch configuration was investigated. The reciprocal interference of Co and Ni and also the interference by other ions was checked. The method was tested with soil and biological samples and good agreement with reference values was achieved. The performance in an automatic system and in non-deoxygenated solutions is discussed.

Spectrophotometric determination of nickel in copper-base alloy with 2-(2-thiazolylazo)- p-cresol

A spectrophotometric method for determination of nickel in copper-base alloy with 2-(2-thiazolylazo)- p-cresol (TAC) is described. The interferences of foreign ions can be eliminated by masking with a mixture of sodium tartrate and sodium thiosulphate. The nickel—TAC complex has low solubility in water, but is soluble in aqueous ethanol. Beer's law is obeyed for 20–70μg of nickel in 50 ml of solution, at pH 5.7. The molar absorptivity at 580 nm is 2.6 × 10 4l.mole −1.cm −1. The method has been applied successfully to determination of nickel in reference samples.

1-(2-Quinolylazo)-2,4,5-trihydroxybenzene as a Reagent for the Spectrophotometric Determination of Nickel(II) and Lead(II)

Abstract The reagent 1-(2-quinolylazo)-2,4,5-trihydroxybenzene (QATB) has been used for developing a method for the spectrophotometric determination of nickel (II) and lead (II). Variables influencing the sensitivity of this method such as wavelength, pH and time have been investigated. The limitations of this method and the effect of interfering ions have also been investigated. Few properties of the complexes formed between QATB and metal ions (Ni and Pb) such as composition, stability and free energy of formation have been determined.

Simple Determination of Nickel in Hydrogenated Oils

A simple rapid method for determination of nickel in hydrogenated oil was investigated. Extraction of nickel with hydrochloric acid instead of asking prior to the atomic absorption spectro-photometry was found suitable for routine analyses. A trace amount of nickel in hydrogenated oil could be sufficiently recovered by the following procedure : 20g of the oil were dissolved in 50100ml of carbon tetrachloride and then extracted three times with 50ml of 0.5N hydrochloric acid solution. Analytical results for several hydrognated oils obtained by this method agreed well with those by the JOCS method. This method may possibly be applicable to margarine and shortening present in various emulsifiers.

Determination of nickel in the serum of occupationally exposed workers, by means of flame atomic-absorption spectroscopy

A flame atomic-absorption spectroscopy method for determination of nickel in the serum of occupationally exposed subjects has been developed. Trichloroacetic add is utilized for precipitating proteins and freeing bound nickel; sodium diethyldithiocarbamate is used as complexing agent and isopropyl acetate as the solvent for extraction. The method is characterized by good accuracy, precision and sensitivity, over a concentration range up to about 20 ng ml . Calcium, which is present in serum in great excess with respect to typical nickel concentrations, does not interfere in the determination of the latter.

Analytical applications of mixed ligand extraction equilibria Nickel-ditbizone-phenanthroline complex

The mixed ligand nickel-dithizone-phenanthroline complex provides a sensitive method for determination of nickel and also permits evaluation of the extraction constant for nickel dithizonate. The value log K ex = −0.7 was obtained, in agreement with a value of −0.2 obtained by others, and in contrast to an earlier value of −2.9. The addition of phenanthroline substantially increases the rate of extraction.

Geochemical Field Method for Determination of Nickel in Plants

Geochemical Field Method for Determination of Nickel in Plants