POLAROGRAPHIC-DETERMINATION OF CYANIDE AS NICKELCYANO COMPLEX IN BLOOD-PLASMA AFTER SELECTIVE EXTRACTION IN A METHYLENE-BLUE IMPREGNATED POLYETHYLENE COLUMN

A method for the determination of cyanide in blood plasma by different ial pulse polarography (DPP) is described without a drastic acidificat ion of the sample. Cyanide was determined as tetracyanonickelate(II)-a nion complex after a microwave-acid assisted cleanup and a selective c omplex extraction in a polyethylene methylene blue (PE-MB) impregnated column. The cyano complex was eluted from the column with water/aceto nitrile and determined by pulse-polarography at -380 mV (Ag/AgCl). The linear range of calibration was obtained from 1.2 to 9.6 mu g of cyan ide with r = 0.99 and RSD = 9% of 1.2. mu g of cyanide. A detection li mit of 40 mu g L-1 was calculated and the recoveries of cyanide from s piked samples were about 80%. This method was compared with the classi cal pyridine-pyrazolone method.