Measurements of the complexing capacity of solutions containing these organic ligands were carried out by a titration procedure followed by DPASV and toxicity tests were carried out using lysosomes isolated from rat liver.The complexing capacity of the physiological medium containing about 13 mg/L of humic acids, expressed as ligand concentrations, was 0.30 and 0.072 µmol/L for cadmium and copper respectively; the corresponding conditional stability constants were 4.2 x 10 increased from 22.3 to 45.3 µmol/L.The analytical methodology used is based on a robust on-line coupling of capillary electrophoresis (CE) or high performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry, equipped with an octopole reaction system (ORS-ICP-MS).
This experiment provides proof that the mechanism of ionization and excitation was influenced mainly by the character of electrons in the low-pressure plasma.
Journal: Journal of Analytical Atomic Spectrometry Volume: 18 - Pages: 897-901 DOI: 10.1039/B303191H Products: µflow PFA-100 nebulizer Abstract: A typical electrothermal vaporization (ETV) using a tantalum was built for low-pressure ICP-AES.
The analytical performance of the ETV was tested and compared with that of a PFA pneumatic nebulizer with a double membrane desolvator (DMD).
The limits of detection of the ETV were obtained in the range of 3.4 ng to 758 ng for Zn, Cu, Co, Fe, and Mg, while those of the PFA nebulizer were in the range of 53 ppb to 286 ppb.
The OH radical showed two rotational temperatures, low and high.
The former were obtained in the range 800 to 1100 K, while the latter were obtained between 18 K.A narrow central channel was formed inside the plasma when the aerosol gas flowed, and atomic emission was observed at the end-on side of the plasma.The system was optimized by changing various operating factors while the Mg signal was monitored.The fulvic acids reduced the cadmium toxicity by about the same amount as humic acids, from 4.4 to 18.6 µmol/L, but they had no effect on copper toxicity.Analysing the chemical speciation of cadmium and copper in the presence of humic components and under toxicity test conditions we can say that the appreciable decrease of EC is not related to changes in their speciation; we can hypothesize that this is due to different processes, as well as to blocking of the lysosomal membrane.On the basis of the shape of the dose-effect curves obtained for cadmium and copper respectively, we can say that the toxic effects of the two metals are different and we can hypothesize that copper could exercise its toxic activity by inhibiting the ATP-driven proton pump and the function of the Cl Products: µflow PFA-100 nebulizer Abstract: Direct nebulization of an aqueous sample was successfully carried out in our laboratory in a lab-built low pressure-inductively coupled plasma (LP-ICP) using a double membrane desolvator (DMD).