Cayman's COX Fluorescent Activity Assay provides a convenient fluorescence-based method for detecting COX-1 or COX-2 activity in both crude (cell lysates/tissue homogenates) and purified enzyme preparations. The assay utilizes the peroxidase component of COXs. In this assay, the reaction between PGG2 and ADHP produces the highly fluorescent compound resorufin that can be analyzed using an excitation wavelength between 530-540 nm and an emission wavelength between 585-595 nm. The kit includes isozyme-specific inhibitors for distinguishing COX-2 activity from COX-1 activity.