Peroxidase enhanced lanthanide luminescence - a new technique for the evaluation of bioassays

A new technique for the enzyme-amplified lanthanide luminescence (EALL) quantification of peroxidase in bioassays is introduced. Several phenolic peroxidase substrates may be used. These are dimerised in the course of the enzymatic reaction and subsequently form luminescent ternary complexes with terbium(III) EDTA. The luminescence signals are enhanced by addition of CsCl and can be read out in a time resolved type of measurement. With the substrate p-hydroxyphenylpropionic acid, a detection limit for horseradish peroxidase of 2 x 10(-12) mol dm(-3) could be achieved.