Fluorometric Determination of Cyanide by the Reaction with Pyridoxal

Abstract

Cyanide produces a fluorescent compound from pyridoxal (PAL) by a catalytic action. The velocity of the reaction could be measured by measuring the fluorescence intensity. For a concentration of cyanide below 10-5M, the apparent initial velocity of the reaction was maintained for 60 min at a concentration of 6×10-4M of PAL, and the initial velocity was proportional to the concentration of cyanide. A simple and sensitive fluorometric method for the determination of cyanide was devised based on the above findings. Cyanide was treated with PAL at pH 7.5 and the fluorescence intensity was measured at pH 10.