Yes, MitoLite™ RED CMXRos stain is well-retained after fixation.

To stain mitochondria of live cells, prepare a 100–500 nM working solution of MitoLite™ Red CMXRos. After staining live cells with MitoLite™ Red CMXRos, cells can be fixed and permeabilized for subsequent probing/staining of other intracellular structures by immunocytochemistry (ICC).

Fixation and permeabilization protocol

1. After staining, wash cells in fresh, pre-warmed buffer or growth medium.
2. Remove buffer or medium, and replace with 3.7% formaldehyde in complete growh medium at 37°C for 15 minutes.
3. After fixation, rinse cells several times in buffer.
4. Permeabilization (optional): Incubate fixed cells in buffer containing 0.2% Triton^® X-100 for 10 minutes. Following permeabilization, rinse cells in buffer before proceeding with any subsequent ICC staining.