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Centrifuges


runwestierun

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With Lab centrifuges, I would assume the materials used cannot not be contaminated by normal chemicals or biological agents.

I would never assume that!

I've used lab centrifuges, cleaned up dirty rotors, and after a spill of a radioactive liquid in one--usually from a failure of a tube or bottle placed into the rotor--that cleaning is really instructive, because it may feel clean and look clean but the geiger counter tells you there's still stuff left on it. These were not rotors being used with stuff that would make the rotor radioactive, just biological samples with very low-level radioactivity in them that would sometimes be very very hard to clean off.

I absolutely would NOT assume the materials used cannot be contaminated. That's why we kept special centrifuges for use only with certain types of materials (the 'hot' 'fuges for working with radioactivity, the 'clean' 'fuges used only with cultured cells and never general lab chemicals, etc).

One other consideration for working with centrifuges: maintainance. These get inspected and maintained in labs, records are kept of how old particular rotors are and, IIRC, especially for the really high-speed ones, I think records are sometimes kept of how many hours a rotor has been used, and then they are removed from service before they get over their rated limits.

You have to keep them very clean, because a sticky cup for your centrifuge tube may mean you can't get your lovely separated liquid back out, or that your rotor becomes unbalanced (and you saw lots of photos of that above), and you have to be careful too about what you put in them--never taking a chance that 'this tube looks sort of ok' because that leads to dirty rotors and back to the beginning of this post.

That said, it would be quite a lot of fun to have one around, if someone else was taking care of it!

Edited by Wholemeal Crank (log)
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"--I would never assume that!

I've used lab centrifuges, cleaned up dirty rotors, and after a spill of a radioactive liquid in one--usually from a failure of a tube or bottle placed into the rotor--that cleaning is really instructive, because it may feel clean and look clean but the geiger counter tells you there's still stuff left on it. These were not rotors being used with stuff that would make the rotor radioactive, just biological samples with very low-level radioactivity in them that would sometimes be very very hard to clean off.--"

Isn't that what I said?

dcarch

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With Lab centrifuges, I would assume the materials used cannot not be contaminated by normal chemicals or biological agents.

However, if they had been used for radioactive material, that can be very different. I don't think there is an easy way to clean radioactive contamination.

dcarch

I would never assume that!...

I absolutely would NOT assume the materials used cannot be contaminated. That's why we kept special centrifuges for use only with certain types of materials (the 'hot' 'fuges for working with radioactivity, the 'clean' 'fuges used only with cultured cells and never general lab chemicals, etc)....

Isn't that what I said?

dcarch

Maybe, but I took your post to mean normal chemical or biological agents pose no contamination problem.

I took Wholemeal Crank's caution to be that monitoring of radiation during clean-up indicates that centrifuges can readily be contaminated with whatever they are used with. Radioactive materials can readily be tracked with appropriate detectors, which do not universally detect all chemical or biological agents so one should not assume centrifuges or other lab equipment are free from contamination.

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“----My centrifuge was clean inside, and with a wipe down with a bleach soaked rag and soaking the buckets in the same, it's been fine. Your food will most likely be in test tubes, plastic containers you've bought (like me) or heat sealed bags (like Cooking Issues), so contamination will be highly unlikely.---“

My comment was responding to the above.

I was very concerned that is not good enough. I guess I was a little too breif in my response. The materials, such as high corrosion resistant stainless steel, while cannot be easily contaminated by normal agents and can be cleaned by the above method, however, if the equipment was used for radioactive material, that would be highly questionable.

I was involved with the Rockefeller University Department of Comparative Pathology. There they have many ultra centrifuges in use for radioactive type of materials for research.

I just visited Regeneron’s brand new major research laboratory here in NY. I have seen what they are using some of their centrifuges.

I would be very careful in using some of these equipment for food.

dcarch

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I took Wholemeal Crank's caution to be that monitoring of radiation during clean-up indicates that centrifuges can readily be contaminated with whatever they are used with. Radioactive materials can readily be tracked with appropriate detectors, which do not universally detect all chemical or biological agents so one should not assume centrifuges or other lab equipment are free from contamination.

Exactly!

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Rule #1 - Never buy a centrifuge when the eBay address is Yucca Mountain Nevada or Hanford Washington

Rule #2 - See rule #1

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"A cloud o' dust! Could be most anything. Even a whirling dervish.

That, gentlemen, is the whirlingest dervish of them all." - The Professionals by Richard Brooks

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"--I would never assume that!

I've used lab centrifuges, cleaned up dirty rotors, and after a spill of a radioactive liquid in one--usually from a failure of a tube or bottle placed into the rotor--that cleaning is really instructive, because it may feel clean and look clean but the geiger counter tells you there's still stuff left on it. These were not rotors being used with stuff that would make the rotor radioactive, just biological samples with very low-level radioactivity in them that would sometimes be very very hard to clean off.--"

Isn't that what I said?

dcarch

DCarch - I think it was easily missed that your statement was a double-negative. You said you assumed the materials used 'cannot NOT' be contaminated...and it was read that you said the materials 'cannot be contaminated.' I got where you're coming from!

PastaMeshugana

"The roar of the greasepaint, the smell of the crowd."

"What's hunger got to do with anything?" - My Father

My first Novella: The Curse of Forgetting

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  • 2 months later...

I just bought a centrifuge - a Beckman TJ-6 with refrigeration, the same one that Jethro has. I spun peas and corn (separately) last night and I got a 5-mm layer of pea butter after 3 hours. Corn also separated into three distinct layers, the most interesting of which was a thick, syrupy corn water. I used a BlendTec blender to get a very smooth puree before centrifuging, which I imagine helped quite a bit.

I'm planning to keep on experimenting with everything that I can blend and separate... mushrooms, asparagus, leeks, onion, cucumber, coffee, water, wine...

If there are any substances you'd like to see tested, please let me know.

SCOTT HEIMENDINGER
Co-Founder, CMO

Sansaire

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  • 3 years later...

Just picked up a 1 liter capacity swinging bucket centrifuge. I have modernist cuisine. What recipes should I make first to really see the potential of a centrifuge?

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Just picked up a 1 liter capacity swinging bucket centrifuge. I have modernist cuisine. What recipes should I make first to really see the potential of a centrifuge?

 

The Justino recipes from Liquid Intelligence spring to mind - fruit (in the book's case bananas) blended with booze (rum) in a high-speed blender until relatively homogenous, then clarified in a centrifuge. I don't like bananas personally, but apparently it's damn good.

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I have Liquid Intelligence as well, i'll check it out.

 

The Justino recipes from Liquid Intelligence spring to mind - fruit (in the book's case bananas) blended with booze (rum) in a high-speed blender until relatively homogenous, then clarified in a centrifuge. I don't like bananas personally, but apparently it's damn good.

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