Caspase 9 substrate

Cyt c from equine heart was from Sigma-Aldrich^® (St. Louis, MO) and HA-NH₂ (10 kDa) from Creative PEGWorks (Winston-Salem, NC). The dithiobis(succinimidyl propionate) (DSP) cross linker was obtained from ProteoChem™ (Loves Park, IL). The cell lines A549 (human lung adenocarcinoma; ATCC^® CCL185 ™) and COS-7 (African green monkey kidney fibroblast) cells were from the American Type Culture Collection (Manassas, VA). CellTiter 96 aqueous non-radioactive cell proliferation assay was from Promega Corporation (Madison, WI). NucBlue^® Fixed Cell ReadyProbes^® Reagent (4′,6-diamidino-2-phenylindole, dihydrochloride, DAPI), fluorescein (FITC), Annexin Dead Cell Apoptosis Kit with Annexin V Alexa Fluor^® 488 and propidium iodide (PI) were purchased from Invitrogen (Carlsbad, CA). Caspase colorimetric assay kit was purchased from BioVision, Inc., San Francisco, CA and the caspase 9 substrate was from Sigma Aldrich (St. Louis, MO). All other chemicals (reagentor analytical grade) were purchased from various suppliers and used without further purification.

Hydrazine and ammonium bromide were purchased from Merck (Germany). 3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazoliumbromide (MTT), rhodamine, caspase 9 substrate and Caspase-3 Detection assay Kit were purchased from Sigma Aldrich (St Louis, MO, USA). Cell culture medium, penicillin–streptomycin, and fetal bovine serum (FBS) were obtained from Gibco (Gibco, Grand Island, NY, USA).