FLOW-INJECTION ANALYSIS OF TANNIC-ACID WITH INHIBITED CHEMILUMINESCENT DETECTION

Tannic acid was found to inhibit chemiluminescence of the luminol-H2O2 reaction catalyzed by Cu2+. The mechanism of inhibition was investiga ted by chemiluminescent spectra, UV-visible spectra and variation of r eaction conditions. A Row injection method has been developed for the determination of tannic acid based on the inhibition of the chemilumin escence of the luminol-H2O2-Cu2+ system by tannic acid. The method is simple, selective and sensitive with a detection limit of 9x10(-9) mol /l. It is effective to determine tannic acid in the range of 7x10(-8)- 1x10(-5) mol/l. The variation coefficient of eleven determination for 6x10(-7) mol/l tannic acid is 2.5%. The method has been successfully a pplied to the determination of tannic acid in real Chinese gall and ho p pellets samples. (C) 1998 Elsevier Science B.V.