RATE MEASUREMENTS OF BIOMOLECULAR REACTIONS USING ELECTROCHEMILUMINESCENCE

A biomolecular reaction, such as an enzymatic or affinity binding reaction is effected in an electrochemical cell with a mixture of reagents including a luminophore which will relate the concentration of a reactant, a reaction partner or the reaction product of a reaction partner to the electrochemiluminescent intensity, in order to determine the rate of the biomolecular reaction. The reaction partner is a reagent which reacts with the reactant and which itself or its reaction product participates with the luminophore to cause ECL emmissions. The ECL intensity is modulated with a series of electrical pulses which are applied to the mixture of reagents at a preselected potential for preselected intervals of time and duration. The intensity is measured during those intervals to provide a timed series of values (P). The same experiment is repeated twice more, once wherein the modulation is conducted after the reaction has gone to completion to obtain the timed series of values (C), and the last time the reaction is performed in the absence of the reaction partner to obtain the timed series of values (B). The results are normalized (N) using the formula I to obtain a series of values (N) which are plotted to obtain the time course of reaction.