Accelerating aging for blood collection

Goal: Quantitatively measure that blood specimens collected in TokuKit for cytometry remain stable over a period of time.

Of course, we can do this the old-fashioned way, and just wait 24 months. And we are. However, there’s another method, using the Arrhenius equation, which allows us to “accelerate the aging” process. As we measure the “old-fashioned” way, we’ll update our stability assessment accordingly.

The normal storage temperature for TokuKit is -80°C. For accelerated aging, we used -30°C. We derived the days from the Accelerated Aging calculator, referenced by the American Society for Testing and Materials (ASTM), as follows:

For this, we used T_AA = -30C, T_RT = -80C, Q₁₀ = 2, and Desired Real Time (RT) = 723 days.

Example 1: in our mass cytometry experiment, we stored the sample at -80°C for one year to naturally age the specimen. We then transferred the sample to -30°C for 12 days to mimic the second year of -80°C storage. This is the “accelerated” part of the experiment.

Example 2: in our spectral flow experiment, we stored the sample at -80°C for 1 week to establish a baseline. We then transferred one aliquot to -30°C for 23 days. This yields the “accelerated” to 2 years, mimicking two years at -80°C.