Flow injection chemiluminescence determination of catecholamines with electrogenerated hypochlorite Original Research Article

A flow injection method for the determination of catecholamines based on the inhibition of the intensity of chemiluminescence from the luminol–hypochlorite system is described. The hypochlorite was electrogenerated on-line by constant current electrolysis, resulting in the elimination of the instability of hypochlorite solution prepared from commercially available sodium hypochlorite. The detection limits are 6×10−10 g ml−1 for dopamine, 8×10−10 g ml−1 for adrenaline and 8×10−10 g ml−1 for isoprenaline. Linear ranges are 1×10−9–2×10−8 g ml−1 for dopamine, 2×10−9–2×10−8 g ml−1 for adrenaline, 2×10−9–2×10−8 g ml−1 for isoprenaline. The relative standard deviations are lower than 2.8%. The proposed method has been applied to the determination of catecholamines in pharmaceutical injections with satisfactory results.