MODIFIED PICRATE METHOD FOR DETERMINATION OF CYANIDE IN BLOOD

Cyanide (cn^- ) is widely distributed in the ecosystem and has been associated with toxic effects in humans and animals. most outbreaks of cn^- poisoning in animals result from ingestion of plants containing cyanogenic glycosides. various analytical techniques for estimating cyanide in blood are available. a simple picrate method was developed to determine blood cn^- in goats. this assay is a modification of commonly available methods using picrate paper and those using conway diffusion cells. cyanide in blood was measured during and after iv administration of kcn at 0.6 mg/min for 1 h. blood cn^- levels in rabbits were determined after oral administration of kcn for 10, 20, 30 and 40 days. the cn^- concentration in blood of goats was time-dependent and continued rising during infusion followed by gradual decline after infusion stopped. a calibration curve set by dissolving various concentrations of kcn in distilled water showed a linear relationship between cn^- concentration and absorbance (r=0.995) ranging from 0.3-120 mg cn^- /l. blood cn^- levels in rabbits showed time-dependent increase with maximum concentration (1.34 mg/l) at 40 days. this is a simple and inexpensive tool for the determination of blood cn^- in the laboratory and under field conditions as well.