DNA Staining FACS is used to study DNA cell content. PI cannot enter live cells and is included in immunofluorescent staining protocols to identify dead cells. Some Hoechst dyes can enter live cells. DNA staining can be used to study the cell division cycle. Relative DNA content shows the proportion of cells in G1, G2 and S phases.
Apoptotic cells show characteristic smear on DNA staining.
Measuring apoptosis in cells after irradiation Calcium Flux and Other Metabolic Studies FACS can be used to investigate cell biology. Calcium flux can be measured using Indo-1 markers. This can be combined with immunofluorescent stain. For example, identify T cell subpopulations by immunofluorescence and measure calcium flux in response to an activating signal. Rhodamine-123 stains mitochondrial membranes is used to measure cellular activation.