SOLVENT-EXTRACTION OF CADMIUM AS A PREVIOUS STEP FOR ITS DETERMINATION IN BIOLOGICAL SAMPLES BY ELECTROTHERMAL ATOMIZATION ATOMIC-ABSORPTION SPECTROMETRY
Jme. Almendro et al., SOLVENT-EXTRACTION OF CADMIUM AS A PREVIOUS STEP FOR ITS DETERMINATION IN BIOLOGICAL SAMPLES BY ELECTROTHERMAL ATOMIZATION ATOMIC-ABSORPTION SPECTROMETRY, Talanta, 40(11), 1993, pp. 1643-1648
A method is proposed for the solvent extraction of cadmium using 1,5-b
is(di-2-pyridyl-methylene)thiocarbohydrazide (DPTH) as extractant. The
optimum extraction conditions were evaluated from a critical study of
the effect of pH, concentration of extractant, shaking time and ionic
strength. The maximum volume ratio of the aqueous to organic phase wa
s 30:1 for a single-stage extraction of 99-100% of the metal ion. The
detection limit is 0.01 ng/ml cadmium, and the calibration is linear f
rom 0.1 to 5 ng/nil. The relative standard deviation for 10 replicate
measurements is 1.8% for 2 ng/ml cadmium. The extraction method was ap
plied to the determination of cadmium in some biological materials usi
ng graphite furnace atomic absorption spectrometry.