Can I intracellularly measure mitochondria calcium flux and changes in mitochondria membrane potential at the same time?

Yes, you can. By using a low affinity fluorescent calcium indicator, e.g., Calbryte-520 AM or Fluo-4 AM, and a mitochondria membrane potential marker such as TMRM, you can simultaneously monitor mitochondria calcium flux and membrane potential changes at the same time.

For a detailed protocol, please refer to the article below.