Flow injection chemiluminescent detection of gallic acid in olive fruits

One economic and environment friendly flow injection chemiluminescent method for the determination of gallic acid was developed. It was based on the inhibited chemiluminescent emission of alkaline luminol–KMnO4 system by gallic acid. The logarithm of the difference of chemiluminesent intensity of the alkaline luminol–KMnO4 system in the absence of gallic acid from that in the presence of gallic acid was linear with the logarithm of the concentration of gallic acid in the range from 1.0 × 10−9 to 5.0 × 10−5 g ml−1 with a detection limit of 2.2 × 10−10 g ml−1. The relative standard deviation of eleven determinations of 1.0 × 10−6 g ml−1 gallic acid was 1.7%. The method was successfully applied to the determination of gallic acid in olive fruits.