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Plasma-Filled Bags Could Replace the Petri Dish

samzenpus posted more than 2 years ago | from the disposable-lab dept.

Science 43

Zothecula writes "The humble Petri dish may soon be a thing of the past. A team of researchers in Germany have developed a new technique for treating plastic bags with plasma to turn them into sealed, sterile containers suitable for microbiology work with much less chance of contamination than traditional containers. This holds the promise of not only decreasing the possibility of contamination in stem cell and live-cell therapy techniques, but also the potential for cultivating whole human organs for transplant surgery."

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Supreme Court to take up Health Care Law (-1)

Anonymous Coward | more than 2 years ago | (#38048996)

Soon to find it unconstitutional - possibly by June of 2012.

What could possibly go wrong? (1)

Anonymous Coward | more than 2 years ago | (#38049004)

A bag. It's an awesome idea because we live in a world without sharp objects or smart sounding/looking stupid people.

ex-wife (0)

Anonymous Coward | more than 2 years ago | (#38049016)

That was my cute nick name for my ex-wife "Plama Filled Bag"

Lucky breaks (0)

Anonymous Coward | more than 2 years ago | (#38049020)

If we'd had this before, we could have completely failed to discover Penicillin.

Re:Lucky breaks (2)

ackthpt (218170) | more than 2 years ago | (#38049158)

If we'd had this before, we could have completely failed to discover Penicillin.

I believe the discovery of Penicillin was rooted in an observation (a great scientific tool) that peasants didn't seem to suffer certain ailments as often as their masters (so to speak.) A theory (another great scientific tool) was formed, the difference may be diet related (Lord knows the peasant and labourer lived in pretty filthy surroundings.) Examination (yet another great scientific tool) of diet revealed the hardy peseants eating mouldy bread. The bread mould was tested (gads, science is amok with great tools!) in a petri dish and found to kill certain bacilli (which should have been no surprise because certain of the funghi family mistook for the more edible varieties can kill people, with or without a petri dish.) Perhaps it could have been observed in a bag, but bags are so difficult to get under a microscope.

Science - It's full of tools.

Re:Lucky breaks (1)

bolthole (122186) | more than 2 years ago | (#38050916)

Science - It's full of tools

What you seem to be saying is, "common laborers are the most useful tools for science".

To which I reply, yup, that's pretty much how things work. For all kinds of science. *especially* "political science". A body cant get elected, without a bunch of tools voting for them these days...

plasma or plasma (5, Informative)

smoothnorman (1670542) | more than 2 years ago | (#38049120)

Perhaps someone else wondered (given that this is an article about microbiology) if the "plasmas" in the summary is of the 'blood plasma' sort or rather the ionized gas sort. You may save yourself a click: it's the latter; and its function is mostly to sterilize to sample space. Now as to the ease of subsequent sterile access to the bag, versus a dish with a lid, i leave that to the imagination of the gloved and harried lab tech.

(http://www.etymonline.com/ plasma 1712, "form, shape" (earlier plasm, 1620), from L.L. plasma, from Gk. plasma "something molded or created," from plassein "to mold," originally "to spread thin," from PIE *plath-yein, from base *pele- "flat, to spread" (see plane (1)). Sense of "liquid part of blood" is from 1845; that of "ionized gas" is 1928)

Re:plasma or plasma (0)

Anonymous Coward | more than 2 years ago | (#38049176)

The gasses don't sterilize the bags. They allow cells to adhere to the sides of the bag.

Re:plasma or plasma (1)

thomasdz (178114) | more than 2 years ago | (#38049194)

Highly unlikely, BUT... It could also be referring to the mother of some guy who is named "Pla"

Pla's Ma

Re:plasma or plasma (3, Insightful)

pz (113803) | more than 2 years ago | (#38049552)

Yes, another rather face-planting editorial failure. The summary should have been made clear that it was talking about electrically charged gas as a sterilization agent, since growth media derived from bovine blood plasma is standard stuff for filling petri dishes.

Re:plasma or plasma (1)

tibit (1762298) | more than 2 years ago | (#38049898)

Yeah, I was just wondering: so we have a sterile bag that promotes cell growth (of certain cells, at least). Now, how does that fix contamination of the thing you're going to culture? That's not to be trivially dismissed, I'd imagine that contamination of the "seed" material is just as big of an issue as the contamination of the growth medium.

in canada (0)

Anonymous Coward | more than 2 years ago | (#38049184)

meat is grown and sold in bags

HeLa (4, Interesting)

bcrowell (177657) | more than 2 years ago | (#38049264)

Contamination has been a huge issue in human cell research. A line called HeLa contaminated [wikipedia.org] a large number of experiments, meaning that basically all the research on human cells in vitro from an entire era was called into doubt. The story of the HeLa line is remarkable; they are immortal cancer cells from a woman named Henrietta Lacks. The cells weren't just contaminants; they played a major positive role in a lot of science. Lacks was never asked her permission, and her family never knew for decades afterward that her cells had made such a contribution to medicine.

Re:HeLa (3, Interesting)

Mortiss (812218) | more than 2 years ago | (#38049402)

Not to mention, she can be regarded as a first truly genetically immortal human being in a sense of her cells (or whatever is left of her original DNA given that these cells have been passaged so many times). Someone here has once mentioned her mass if they put together all cells from all the labs in the world. I recall it was ranging into tonnes..

Sue 'em (1)

ThatsNotPudding (1045640) | more than 2 years ago | (#38050562)

Lacks was never asked her permission, and her family never knew for decades afterward that her cells had made such a contribution to medicine.

They should sue for blatant IP theft, MAFIAA style, say $1 million for every copied cell.

Re:Sue 'em (0)

Anonymous Coward | more than 2 years ago | (#38052424)

They did actually.

Not that new (3, Interesting)

SydShamino (547793) | more than 2 years ago | (#38049272)

The ways in which one atmosphere plasmas modify material properties, such as with this plastic bag, aren't new at all. My college professor in a graduate course on nuclear fusion (an elective while I was an undergrad) discussed them more than a decade ago. The only thing I see that is remotely new is creating the plasma after the bag is sealed, rather than creating the plasma externally and then piping it into the bag.

Unfortunately the technology got all tangled up with the government, and then a number of people (including my former professor) were arrested for sharing "secrets" about this technology with "foreign nationals". So of course now all the public scientific advances in this field have to come from some other country.

http://www.knoxnews.com/news/2008/jun/24/atmospheric-glow-to-sell/ [knoxnews.com]

Re:Not that new (1)

Swanktastic (109747) | more than 2 years ago | (#38049582)

That's a really interesting story and probably not uncommon. I'm sure everyone has their horror stories about the startup that was born in an academic institution. It's such a problem and the university technology licensing / outreach administrators who are tasked with fixing it are complete dimwits.

Petri dishes aren't going anywhere. (4, Informative)

TheClockworkSoul (1635769) | more than 2 years ago | (#38049468)

This seems more like marketing hyperbole than anything else. They're just sterile bags (though the pictures of the plasma sterilization are kind of cool). You don't need plasma to sterile a bag: if we really wanted to use bags for tissue culture, we would have had them 30 years ago.

As a graduate student in the field, I can tell you that the humble petri dish has FAR too may uses, and is far too easy to use, to ever be replaced by something as awkward as a bag for pretty much anything. I suppose that the bags could perhaps be used for some function that's currently being served by the (also enclosed and sterile) flasks [wikipedia.org] that we usually use for tissue culture tissue culture [wikipedia.org], but bags are harder to stack in an incubator, where space can often be in short supply.

Whiz-bang hyperbole aside, plasma-sterilized bags will probably find a niche use in which it would be handy to culture in a container that can be easily cut away, tissue engineering comes to mind, but to assert that petri dishes are going the way of the dodo is patently absurd.

Re:Petri dishes aren't going anywhere. (1)

Anonymous Coward | more than 2 years ago | (#38049960)

to assert that petri dishes are going the way of the dodo is patently absurd.

Especially as these bags have been specifically designed for tissue culture. The article briefly mentions bacteria and then totally disregards the role petri dishes have in bacterial and other culture.

You cannot pour agar into one of these bags, and even if you try injecting it with a needle like they suggest, you can't streak bacterial cultures to single colonies or spread plate cultures, place antibiotic strips onto the surface, isolate colonies from the surface of it, blot it, look at it under a microscope with the uneven and apparently translucent plastic material or easily count colonies on the agar, if the bag has no solid support.

In fungal culture you normally remove a small cylinder of the agar with fungal tissue on the surface using a cork-borer like tool, and place that onto the surface of the new agar plate. You can't do that with these bags. Measuring radial growth will also be a pain.

All of these are bog standard, every-day microbiological techniques. Even seeing colony morphology through those translucent bags could be awkward. To top it all off, the article finishes with

And, being simply plastic bags, they are disposable, which removes the cost of cleaning and re-sterilization

They've clearly never heard of plastic disposable petri dishes then.

I'm not saying these bags aren't useful, but whoever wrote the article A) completely ignored the massive number of non-tissue culture uses for petri dishes and B) hasn't ever heard of common, cheap, disposable alternatives to the glass dishes. Petri dishes aren't going anywhere.

Re:Petri dishes aren't going anywhere. (1)

subanark (937286) | more than 2 years ago | (#38051144)

I would also like to add that this is really designed for animal cells. Plant cells want a more solid environment.

Re:Petri dishes aren't going anywhere. (0)

Anonymous Coward | more than 2 years ago | (#38055594)

Too bad animal cells need oxygen and ~5%CO2 to grow, neither of which would easily get in with ruining the sterility. Also, Trypsinization, a required technique for mammalian cell culture would be really difficult in a bag. As a cell biologist, I can see very few places that this would be of any use, let alone replace petri dishes. Also, the article cites that it removes cleaning and sterilizing from being a problem; nobody in their right mind reuses glass dishes, It's at most 50 cents for a brand new sterile plastic plate that's treated for tissue culture.

Re:Petri dishes aren't going anywhere. (1)

FlavaFlavivirus (2021178) | more than 2 years ago | (#38054492)

Agreed. This is the classic example of solving a problem that doesn't exist. Want to limit contamination of flasks during growth? How about a filtered cap on the flask, or a HEPA filter in the incubator, or antibiotics in the media...oh wait, we already do that.

Linguistically Inelegant (2)

Ukab the Great (87152) | more than 2 years ago | (#38049594)

"Your nasty bathroom's a plasma-filled bag" just doesn't roll off the tongue like "Your nasty bathroom's a petri dish".

mod dOwn (-1)

Anonymous Coward | more than 2 years ago | (#38049792)

Obliga7ed to c5are

so bad, it's not even wrong (0)

Anonymous Coward | more than 2 years ago | (#38049802)

almost no one uses glass petri dishes anymore; almost all are Polystyrene, and all for growth of mammalian cells are treated with plasmas or more sophisticated coatings; the plasma work was done, I think, in the 60s, mainly at corning (eg, I have papers where they used esca and mass spec to look at how the surface composistion changed with plasma time and ratio; a big problem in the early work was that plasma made the polystyrene soluble, if your plasma was to aggressive)
Scientists and lab equipment vendors have long recognized the problems with petri dishes, and you can buy today, and have been able to buy for many years, various bags and other formats
google corning or costar or nunc nalgene, among just a few of the bendors

etc etc

the inventive powers of science (3, Insightful)

bolthole (122186) | more than 2 years ago | (#38049924)

Congratulations, scientists.
After thousands of years to hone your skills, you have achieved the ultimate pinnacle of biological knowlege:

Turns out, a uterus is a good idea for growing organic things.

In another thousand years, they might come up with an equally brilliant invention: a "post-uteral sustanance device, with intuitive interface"
They could call it a Biogrowth-Optimized Organic Bladdersack

Re:the inventive powers of science (0)

Anonymous Coward | more than 2 years ago | (#38050226)

Sorry, no. I've been doing tissue culture for 20+ years. For the vast majority of folks doing tissue culture, this is in no way a valid replacement for the petri dish, flask, or roller bottle. Only a tiny niche among folks doing tissue culture will find value in bags.

Re:the inventive powers of science (0)

Anonymous Coward | more than 2 years ago | (#38051614)

As an amateur mycologist who has grown mycelium in bags for years, care to expand on the disadvantages? I would grow cultures in broth inside a sealed bag, using a syringe to inject/remove broth through a self-healing injection port. I did have bags occasionally go bad, but I was certainly not using scientific grade materials.

Re:the inventive powers of science (0)

Anonymous Coward | more than 2 years ago | (#38053070)

Unless those bags are fat-filled, come in symmetrical pairs, are warm and soft, and attached to one easy on the eyes, oh yeah, and have nipples... in which case I can think of a number of uses... :^) oooohhhh... yeahhhh...

what is the innovation here? (0)

Anonymous Coward | more than 2 years ago | (#38050024)

I'm a biologist and I don't see the big deal here. How is this different from the pre-sterilized bags I've been getting for years? How is this cheaper than the lowly petri dish?

I invented this. (0)

Anonymous Coward | more than 2 years ago | (#38050346)

No really, I invented this. I was using culture bags to propagate mushroom mycelium (no, not the magic kind) years ago. Nutrient broth sealed in bag, high-flow microfiltration patch, sterilize in pressure cooker, inject the inoculant through self-sealing injection port. I kept it a secret from all the dumbasses who were futzing around with flow hoods and Erlenmeyer flasks. I see I was right to be secretive about it, apparently actual microbiologists hadn't even thought of it either.
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