Ultra-low temp freezer

I have looked at that route too. From what I calculated, -20 °C might give one to two years of stability and -40 °C maybe two to three, while ultra-low temps used in labs could stretch it to three to five years. There are no actual studies though, so it is all guesswork.

Those numbers were in Celsius, so -20 °C equals -4 °F.

Not sure indefinite storage is realistic at any temperature. These compounds have not been around long enough for proper data. Still, -40 should keep them viable for a very long time. My worry is that after a few years the material might lose potency or, worse, cause sensitivity or an allergic reaction if it has broken down.

That was my main concern. I ran the numbers on the smallest model I could find and it came to roughly two hundred dollars a year on paper, probably more in practice. Spending that much on power for only a couple extra years of shelf life does not seem worth it, especially when I would want fresh testing after that long anyway. I might still try one just to see how far I can push the stability, for my own curiosity.

On the highest setting and our current rate, my small 1.1-cubic-foot unit works out to about sixty dollars a year. Other people report thirty to thirty-five dollars, though that feels low. I am running it a few degrees below its maximum and will check actual usage once the weather cools.

If it were me I would fill the empty space with water bottles. They improve efficiency while the compressor runs and help hold temperature longer during an outage. I do the same thing with my garage unit.

#thermalmass

You just activated another math enthusiast. That really is the single point where the two temperature scales meet.

I have seen lab freezers described as running anywhere from -20 °C to -50 °C. My own two-cubic-foot chest unit sits at -22 °C all the time and that is the extent of the science I am willing to track. If a vial can sit in someone’s garage for ten years and still test nearly full strength, then what I have should keep future supplies close to full potency.

I already have a whole-house generator, but the water-bottle idea is still useful.

My plan is simply to pack the unit full of product so there is less air space to lose cold. You might consider the same approach.

Filling it also lowers the power needed to maintain temperature once everything is cold.

That story was about a different compound. The physics do not line up with the claim being made here.

That claim was overstated and contradicted by plenty of existing evidence. The testing only measured purity, not the stability issues that actually appear in lyophilized material. The same source also suggested reconstituting with plain sterile water because the preserved version is not common in their region. Keep in mind this is someone without formal biopharma training running an uncertified lab.

-80 °C sits below the glass-transition temperature of known peptide formulations, so degradation essentially stops. Going even colder slows the tiny remaining rate only a little more. The jump from -20 °C to -80 °C cuts degradation dramatically, but another sixty degrees adds almost nothing noticeable except over decades. For a multi-year stockpile the extra cold can still make sense.

It is overkill. One of the less stable compounds stayed fine after years in an ordinary freezer according to available tests. My own unit is set to -25 °C and that appears adequate for long-term needs.

I have heard of lining the bottom and sides with gel packs and then another layer on top of the stored items.

Do you know where that interview can be found? I have not been able to locate it.

It came from another user’s post in this thread.

At some point you hit diminishing returns, but even a few extra percent of stability can still matter.

My point exactly. The gap between -25 °C and -40 °C looks small over two or three years. A little extra product would probably cover any difference. I am mainly focused on the less stable compounds and the data suggest they hold up fine at -25 °C.

Now I am confused. I always thought a full freezer helped both efficiency and outage protection, and a friend agrees. Am I missing something?

Any degraded material could in theory make the immune system develop an allergy, even if the chance is low. Would you use a vial that tested at only 95 percent? I would not.

All right, I will look for small water bottles then. I am not spending that much on a small freezer.

That reaction is not going to occur if the material stays frozen.

Thanks, I watched it. I still wanted to hear the full interview myself.

I only heard about it second-hand from another poster, so I would not repeat it as fact.

Are you going through the whole thread checking every third-party claim?

The thread has some information on that, but I am comfortable with the steady -22 °C my thermometer shows.

I am fortunate.

Would renting space be an option for you?

I have read about that facility. It sounds like a worthwhile project. That said, I have a few kits I might ask them about.

Thermal mass does act like a battery and slows how fast the average temperature changes. It does not improve the insulation itself, so heat still transfers at the same rate. A fuller unit may cycle less often but the compressor has to run longer each time to bring everything back down. The part about air spilling out when the door opens is correct because air is part of the thermal mass. In the battery analogy, a larger battery keeps the lights on longer but still needs the same charging time afterward. Clear as mud?

Fahrenheit or Celsius?