4.2.4. Effects of Samples on the COX-1 and COX-2 Activity

Samples were evaluated for its potency and selectivity of inhibition in vitro using COX Inhibitor Screening Assay (Cayman, Michigan, MI, USA). Recombinant COX-1 (ovine) or COX-2 (human) proteins were pre-incubated with Compound 3 for 10 min at 37 °C. The reaction was started by the addition of 100 µM arachidonic acid and allowed to proceed for 2 min. The reaction was terminated by the addition of an HCl solution containing SnCl₂. The COX activity assay directly measures PGF2α produced by SnCl₂ reduction of COX-derived PGH₂. The prostanoid product is quantified via EIA. As control inhibitors for COX-1 or COX-2, SC-560 (100 nM) or Dup-697 (100 nM) were used.