Sterilizing injection pen cartridges

GimmeABreak

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I ordered a handful of cartridges from two different pen suppliers and they claim they are sterilized but no real way to be certain. Is there a way I can sterilize them in my lab? I searched this on other forums + reddit and can't seem to find any info. Insta pot? UV Light? With either of these methods, if the cart is sealed does sterilization even work?
TIA
 
I've heard of several taking them to a dentist office or doctor's that they're close with and sterilize with their equipment. Not sure how Insta Pot would work but maybe?
 
Yes, asking a vet, dentist, doctor, or even a school if they will autoclave it for you will work.

Unfortunately an Instant Pot does not get hot enough. I believe the sterilize function only gets to about 239F (118C) . You want to reach a temp of 250F (121C) for 15-20 mins. I know some may say close enough but it is up to you to decide your amount of risk.

A manual pressure cooker with a 15psi weight works. This is what I use and yes the tape does turn from blue to black.
 
Yes, asking a vet, dentist, doctor, or even a school if they will autoclave it for you will work.

Unfortunately an Instant Pot does not get hot enough. I believe the sterilize function only gets to about 239F (118C) . You want to reach a temp of 250F (121C) for 15-20 mins. I know some may say close enough but it is up to you to decide your amount of risk.

A manual pressure cooker with a 15psi weight works. This is what I use and yes the tape does turn from blue to black.
Thanks for the quick response. So something like this would work:


Any idea how long it would take?
 
Yes, asking a vet, dentist, doctor, or even a school if they will autoclave it for you will work.

Unfortunately an Instant Pot does not get hot enough. I believe the sterilize function only gets to about 239F (118C) . You want to reach a temp of 250F (121C) for 15-20 mins. I know some may say close enough but it is up to you to decide your amount of risk.

A manual pressure cooker with a 15psi weight works. This is what I use and yes the tape does turn from blue to black.
Genuinely curious… why 250 F when the FDA says 165F for food born bacteria?
 
Yes, asking a vet, dentist, doctor, or even a school if they will autoclave it for you will work.

Unfortunately an Instant Pot does not get hot enough. I believe the sterilize function only gets to about 239F (118C) . You want to reach a temp of 250F (121C) for 15-20 mins. I know some may say close enough but it is up to you to decide your amount of risk.

A manual pressure cooker with a 15psi weight works. This is what I use and yes the tape does turn from blue to black.
I’m trying to figure this out. How do the cartridges get sterilized inside of the packaging, sealed at both ends with rubber stoppers? Just by virtue of the temp?

ETA: ok, I got part of it, medical grade kraft paper is permeable. The second part, the rubber stoppers…idk.
 
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I’m trying to figure this out. How do the cartridges get sterilized inside of the packaging, sealed at both ends with rubber stoppers? Just by virtue of the temp?

ETA: ok, I got part of it, medical grade kraft paper is permeable. The second part, the rubber stoppers…idk.
Pressure causes the stoppers to pop out. You re-insert them while still packaged.

I haven’t actually done this personally but this is my understanding of it
 
Genuinely curious… why 250 F when the FDA says 165F for food born bacteria?
Honestly, I don't know. I did a LOT of reading on it and that keeps coming up. I also asked a dermatologist that I have worked with for years and she said her practice autoclaves at 121C. Which she kindly did my first batch.
https://www.sciencedirect.com/topics/engineering/steam-sterilization has some information and a nice timing chart.
I think it comes down your risk tolerance level.
 
Thanks for all of the reply's. I am either going to go with the $40 autoclave (in the amazon link above) or just roll the dice and hope the cartridge vendors actually sterilize them.... (TAKE THAT! immune system)
 
Where I work we sterilize things at 270F for 8 minutes. Unless it’s a fluid or needs to be run on a special cycle.
 
For those that are into mycology sterilizing jars of media are a normal part of our hobby. A standard pressure cooker with weight and a gauge (important) can mimic a 121C 15psi sterilization procedure. Typically I use 30 minutes instead of 20 minutes. Also I like to add a quarter to the weight on my cooker to increase the pressure to 17psi. Make sure to not start your 30min timer until after the pressure reaches >=15psi and you have turned the heat down.

Also here is a chart of time temp psi for sterilizing

And if you buy a pressure cooker and build a still air box you can then get into mycology and grow fungi for fun and health benefits.
 
For those that are into mycology sterilizing jars of media are a normal part of our hobby. A standard pressure cooker with weight and a gauge (important) can mimic a 121C 15psi sterilization procedure. Typically I use 30 minutes instead of 20 minutes. Also I like to add a quarter to the weight on my cooker to increase the pressure to 17psi. Make sure to not start your 30min timer until after the pressure reaches >=15psi and you have turned the heat down.

Also here is a chart of time temp psi for sterilizing

And if you buy a pressure cooker and build a still air box you can then get into mycology and grow fungi for fun and health benefits.
Any thoughts on an Instant Pot? Likely not going to buy a new pressure cooker when cartridges are so cheap, but might dabble with the instant pot.
 
The instapots only get up to 12psi. They are used but you need to increase the run time. I would go 2 hours minimum. The newer instapot max that does 15psi should be ok but I never researched how well they maintain pressure / temperature.
However I would sooner use one of the cheap 6 quart pressure cookers with no gauge but does have a traditional rocker weight that I can manipulate.
 
The instapots only get up to 12psi. They are used but you need to increase the run time. I would go 2 hours minimum. The newer instapot max that does 15psi should be ok but I never researched how well they maintain pressure / temperature.
However I would sooner use one of the cheap 6 quart pressure cookers with no gauge but does have a traditional rocker weight that I can manipulate.
Putting a weight on the rocker weight seems sketchy and a recipe for disaster for most.
 
Putting a weight on the rocker weight seems sketchy and a recipe for disaster for most.
These do 15psi out of the box.

The quarter sits on the rocker weight. If you don't turn down the heat once it gets going the quarter will fall off. It ensures that the weight is just over the minimum for 15psi given the machining tolerances of the rocker weight.
 
Ok, so it sounds like the Insta Pot (that I already own) will do a pretty good job if I run it for 2+ hours? I hate buying appliances or other things that I will only use once or twice.
 
yes, tests with instapot were able to neutralize the geobacillus bacteria after 1:45 min run. Stick to a 2hr run and use a proper sterilization pouch and you should be relatively safe.
 
FWIW, we have a test group going on right now at FPPG Test Group that is testing 4-5 various vendors' pen cartridges if anyone is interested.
 
These are just my most educated guesses - as far as the difference in temperatures between food and the sterilization of injectable tools, it comes down to the fact that when you inject something you are bypassing all of the body’s natural defense systems - skin, stomach acid, enzymes, and the immune system in your gut.
The most common form of bacteria seen in wounds is staphylococcus. If you maintain excellent hand hygiene, use alcohol swabs before you pin and keep a dedicated area that is clean you’re doing good. As for sterilizing the cartridges, I would agree with everyone else who said that it’s a good idea to make sure that they are sterilized.
 
Just curious. How does this affect the rubber. I got some recently from Heaven's store Aliexpress. The rubber stoppers seemed very difficult to move. It almost takes brute force to get them started. I purchased others from EZPENS that uses steam sterilization and those rubber stoppers move very nicely, very smooth.

I think just applying heat, would dry the rubber out? The steam process wouldn't do that. Rubber is a pesty product when it comes to exposure to heat and UV. Just look at what happens to the rubber parts of your car.
 
Suprised with the instapot conversation noone has share this study again
They talk about a few different presure cookers and the
[td]
Instant Pot​
[/td][td]
IP-DUO80​
[/td]​

In this work, we assessed the viability of four brands of 8-quart pressure cooker to sterilize biological consumables and instrumentation. All four brands inactivated the microbes contaminating microbiological culture media and on metal implements within 15 mins and 30 mins of run time, respectively. The pressure cookers tested also inactivated high titers of bacteria and fungi, some of which are medically relevant strains, within 15 mins and 60 mins of run time, respectively. Unlike the other brands tested, the Instant Pot was capable of inactivating 106 G. stearothermophilus spores, which indicates that it can sterilize items to the level generally deemed acceptable for laboratory autoclaves. These data demonstrate that the pressure cookers tested are a viable alternative for steam sterilizing laboratory items when an autoclave is unavailable.
 
Just curious. How does this affect the rubber. I got some recently from Heaven's store Aliexpress. The rubber stoppers seemed very difficult to move. It almost takes brute force to get them started. I purchased others from EZPENS that uses steam sterilization and those rubber stoppers move very nicely, very smooth.

I think just applying heat, would dry the rubber out? The steam process wouldn't do that. Rubber is a pesty product when it comes to exposure to heat and UV. Just look at what happens to the rubber parts of your car.
This thread was very useful. My labels were blue initially. I had a prestige pressure cooker with weight and steamed these for half an hour and the labels turned black. A tiny drop of water was inside the pouch after this, but thats ok as the stopper did not pop out. As far as the stopper being stuck is concerned, I guess its some kind of glue or seal and is intended to be there. I tested one of them before steaming and it was still stuck. I think it surves 2 purposes. To prevent the stopper from popping when steamed. To accidently prevent the Stopper popping out when filling medication without using a second needle to let the air out, and its definitely not steam doing it.

Also I dont know what temperature the pressure cooker went as the bosch infrared thermomenter could not read the temp due to reflective surface of stainless steel. Hope this helps.
 
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We have a testing group where I participated to test a ton of different carts for sterility, some already been sent to Jano
 
Old thread but...

Proper autoclaves run at 15 PSI but it is possible to sterilize at lower pressure and temperature if you do it longer.

This paper tested the Instant Pot and found that it was able to sterilize 1L of liquid media effectively when run for 150 minutes. Scroll down to "Instant Pot pressure cooker passes the spore sterilization test."


These data indicated that the Instant Pot pressure cooker could sterilize spores to the level of an autoclave, and we infer that it would be capable of inactivating all other less heat resistant organisms to properly sterilize laboratory items for research.... All four pressure cookers tested were able to inactivate the microbes present in all of the trials except for the inactivation of G. stearothermophilus spores, in which only the Instant Pot was able to produce steam, pressure, and heat to the level necessary to achieve sterilizing conditions.

Now actually properly treating any particular kind of vial is a different question. (If it is sealed, steam doesn't get inside. If it isn't sealed, how do you assemble it in a sterile manner?) But in general it should be possible to sterilize gear and media in a 12 PSI Instant Pot.

Would I rather have 15 PSI, yes. In fact I bought a 15 PSI Presto pressure canner for my mushroom cultures.
 
The instapots only get up to 12psi. They are used but you need to increase the run time. I would go 2 hours minimum. The newer instapot max that does 15psi should be ok but I never researched how well they maintain pressure / temperature.
However I would sooner use one of the cheap 6 quart pressure cookers with no gauge but does have a traditional rocker weight that I can manipulate.
Someone on STG has been using an instapot - she said there is one model that gets high enough. They have a pinned post about it somewhere
 
I ran my own test... these are as-is, or as I say, "as-manufactured." There's no color change on them nor does it appear that it's necessary..


1746760477679.png
 
I ran my own test... these are as-is, or as I say, "as-manufactured." There's no color change on them nor does it appear that it's necessary..


View attachment 6737
Awesome. Thanks a lot for posting this, gives me some peace of mind. I still steam them though just to be safe. Would you mind sharing from where you purchased these from?
 

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