Luminol–hydrogen peroxide–horseradish peroxidase chemiluminescence intensification by kosmotrope ammonium sulfate

The kosmotropic effect induced by ammonium sulfate (AS) at concentrations greater than approximately 2.8 M allows the marked intensification of chemiluminescence (CL) arising from a conventional luminol–hydrogen peroxide (H(2)O(2))–horseradish peroxidase (HRP) reaction. Because of the kosmotropic effect, CL is intensified by at least three orders of magnitude than that from the conventional HRP-catalyzed luminol reaction with no AS; the linear relationship between the CL intensity and the HRP concentration is established over the range of 0.3 pM to several tens of pM. The novel CL intensification effect on the HRP-catalyzed luminol CL can be stably and reproducibly induced. GRAPHICAL ABSTRACT: [Image: see text] SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s44211-022-00069-8.