Characterizing AO/PI and AO/DAPI viability assays for cell therapy development using the Cellaca MX high-throughput cell counter

Cell count and viability are two distinct and equally critical quality attributes (CQAs) assessed throughout cell therapy development, manufacturing, and product release testing. Reliable viability measurements are essential for monitoring manufacturing processes, assessing product quality, and supporting release decisions.

Fluorescence-based membrane integrity assays, including acridine orange/propidium iodide (AO/PI) and acridine orange/4′,6-diamidino-2-phenylindole (AO/DAPI), are widely used to determine cell viability by identifying membrane-compromised dead cells.

This application note compares the performance of acridine orange/propidium iodide (AO/PI) and acridine orange/DAPI (AO/DAPI) viability assays. The key findings suggest important differences in the performance of AO/PI and AO/DAPI viability assays, especially under process-relevant conditions.

For research use only. Not for use in diagnostic procedures.