Catalase cat assay kit

Catalase (CAT) assay kit (Cayman Chemical Company, Michigan, USA) is based on the reaction of the enzyme with methanol in the presence of H₂O₂. The formaldehyde produced is measured colorimetrically with 4-amino-3-hydrazino-5-mercapto-1,2,4-triazole (Purpald) as the chromogen. A standard curve of bovine liver catalase was used for the determination of enzyme activity. One unit is defined as the amount of enzyme that will cause the formation of 1 nmol of formaldehyde per minute at 25°C. Absorbances were recorded at 540 nm wavelength by using microplate plate reader HT BioTek Synergy (BioTek Instruments, USA).

Fetal bovine serum (FBS), antibiotic–antimycotic solution, Dulbecco’s modified Eagle’s medium (DMEM), and phosphate-buffered saline (PBS) were obtained from Gibco BRL, Life Technologies (Grand Island, NY, USA). The Annexin V-FITC apoptosis-detection kit, JC-1, HEMA, dichlorofluorescin diacetate (DCFH-DA) and other chemical reagents, unless specifically stated, were purchased from Sigma-Aldrich (St. Louis, MO, USA). The caspase-3 fluorometric assay kit, caspase-8 fluorometric assay kit, and caspase-9 fluorometric assay kit were obtained from Enzo Life Sciences (Farmingdale, NY, USA). The catalase (CAT) assay kit and superoxide dismutase (SOD) assay kit were obtained from Cayman Chemical (Ann Arbor, MI, USA). The HEMA solution was derived from dimethyl sulfoxide (DMSO), with the final concentration being less than 0.5% (v/v) nontoxic.