Exosomes degrade rapidly at room temperature. One study found significant degradation within 30 minutes at room temperature.⁠ Storage at 4°C (refrigeration) produced more than 70% loss of the CD63 marker over time.⁠ ⁠ The consensus in the literature: -80°C storage is required for long-term preservation of intact and functional exosomes.⁠ ⁠ Now, there is one format where this argument has some nuance: lyophilization (freeze-drying). You remove the water from the exosome, which does extend shelf life. A properly lyophilized powder that is reconstituted at the point of use — meaning right before you put it on your face in the bathroom — that's plausible.⁠ ⁠ But the vulnerable products (and the ones you're most likely buying) are ready-to-use liquid serums sold shelf-stable at room temperature.⁠ When a brand claims proprietary technology to keep their exosomes intact at room temperature for up to 12 months with no refrigeration? That runs against everything in the storage literature.⁠ ⁠ Be...