Alexa fluor 488 annexin 5 propidium iodide kit

Early apoptotic cells were detected using the Alexa Fluor 488 Annexin-V/propidium iodide (PI) kit (Invitrogen, Carlsbad, CA). The apoptosis of A549 cells (1 × 10⁶ cells/well) was measured 24 h after, and cells treated with PBS containing 0.1% DMSO served as negative control. The experimental groups were treated with various concentrations of CoQ0. The quantification of PI and FITC signals was analyzed by a FACSCanto II flow cytometer (BD Bioscience, San Diego, CA, USA). The percentage of stained cells in each quadrant was analyzed using FlowJo software (FlowJo, LLC, Ashland, OR, USA). Cells positive for Annexin-V FITC and negative for PI (Q4 quadrant) were in early apoptosis, and cells positive for both Annexin-V FITC and PI (Q2 quadrant) were in late apoptosis or necrosis.

Apoptosis was detected using an Alexa Fluor® 488 Annexin V/propidium iodide (PI) kit (Invitrogen Life Technologies, Carlsbad, CA, USA), according to the manufacturer’s instructions. In brief, the cells were washed with cold phosphate-buffered saline, and then stained with 5 μl Annexin V-fluorescein isothiocyanate (FITC) and 0.1 μg/ml PI for each 100 μl cell suspension and incubated at room temperature for 15 min. Apoptotic cells were analyzed immediately using a flow cytometer (FACS Calibur 95; BD Biosciences, San Jose, CA, USA) with CellQuest 3.0 software.