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Coffee as a staining agent substitute in electron microscopy
- its_ubuntu 10mo ago[dead]
- hahahahhaah 10mo agoNo... maybe you misread... they said coffee.
- its_ubuntu 9mo ago[dead]
- hahahahhaah 9mo agoI love a rollercoaster comment. Goes up, then down.
- iberator 10mo agoStarbucks doesn't even have good coffee and it's WAY overpriced. It's an abomination. Trust me! Black coffee in McDonald's is superior in quality and price worldwide. Especially in UK and Switzerland. Please explore - Starbucks is baaaad
- cassepipe 10mo agoTrue but on the other hand their coffee beans bags they sell in stores made for the best coffee I have had. I tried to buy beans from coffee snobs independant stores but all I got was weird and/or acidic coffee But hey I am a tea person first and foremost, what do I know
- terribleperson 10mo agoThere are actually a whole bunch of good medium to dark roasts out there, but third wave coffee is hip and has been for a while. If you like Starbucks beans, you'd probably like a better dark roast. Try Lavazza. Coffee snobs will look down on it, but they're highly consistent like Starbucks while offering more variety and more flavor. Lavazza Super Crema makes a pretty nice espresso and is cheap relative to high-end coffees.
- tentacleuno 10mo agoEhh, who cares what the snobs think? Drink what you like! I've been experimenting with coffee for like 2 years, and have found myself really enjoying dark roasted stuff (as well as lighter stuff!) The truth is, you can get a really fruity single-origin bean but as soon as it goes into a latte, typically you've lost 99% of the origin characteristics. It gets a bit wasteful and expensive. Cafes typically go for house roasts that lean darker, and I can see why: they just work better in milk!
- nkrisc 10mo agoI’m going to hate myself for saying this and sounding like such a coffee snob, but: if coffee tastes bad to you, there’s a decent chance you just haven’t had a good cup of coffee. I only say this because I used to hate coffee too, only having had Starbucks or crappy supermarket coffee made at home. But then I had a cup of coffee at a very good restaurant and it was so delicious. It was just black coffee, good beans prepared right. Turns out I just prefer light to medium roasts and found the right brewing times and temps that I like best. Every time I have Starbucks it still tastes awful.
- zafka 10mo agoI was turned on to Chock full o' Nuts years ago, and have never turned back. I will drink any coffee in a pinch, but for great mild coffee I stick to Chock full o' nuts in my french press.
- tentacleuno 10mo ago
- amelius 10mo agoYes, their cappuccino milk is foamy, not creamy. For the price I expect cappuccino art. And they serve it too hot. 3 out of 5 stars at most and subtract one star for the price.
- hahahahhaah 10mo agoOne does not simply ... ordinary espresso.
- jacquesm 10mo agoYou just know how they found out about this... > "I got the idea of using espresso as a staining agent from the circular dried stains in used coffee cups," Suuure...
- bell-cot 10mo agoQuoting more: > "I got the idea of using espresso as a staining agent from the circular dried stains in used coffee cups," says Claudia Mayrhofer, who is responsible for ultramicrotomy at the institute. During preparation, she cuts tissue samples into wafer-thin slices and fixes them onto sample holders. Staining is the last step before examination under the electron microscope. I'm curious about the grad student who is the second author on the research paper. Is he the one tasked with the current-SOP staining with (radioactive and poisonous) uranyl acetate? Was it his overworked-and-drowsy "oopsie" which lead to the discovery?
- fc417fc802 10mo agoAmusing, but no (at least I sincerely hope). Food and wet samples are never in the same vicinity as a matter of OSHA (plus just a general desire not to get yourself or others killed). Violating that would typically be a great way to speedrun getting fired. Radioactive substances go beyond that, generally being handled in their own dedicated area that no one else is permitted to enter for any reason. The level of paranoia is actually fairly impressive (but obviously necessary).
- jacquesm 10mo agoI hope the staining agent is at least visually very different from Espresso.
- bell-cot 9mo agohttps://en.wikipedia.org/wiki/Uranyl_acetate https://en.wikipedia.org/wiki/Uranyl_acetate - so easily distinguished from espresso. OTOH... https://www.google.com/search?q=far+side+comic+culture+of+amoebic+dysentery https://www.google.com/search?q=far+side+comic+culture+of+am...
- amelius 10mo agoMake sure to leave out the hazelnut syrup.
- fredley 10mo agoCalling it now: this is ignobel prize-worthy research. If it doesn’t get a nod I’ll eat my hat.
- Metacelsus 10mo agoNext up: "Coffee in Austria recalled due to high concentrations of heavy metals"
- mjd 10mo agoI'm puzzled by this. Why hasn't there been, over the last fifty years, a huge amount of research into EM staining techniques and which materials were best under which circumstances? Edison supposedly tried 3000 different materials for light bulb filaments before settling on charred cotton thread. Why hasn't something similar been done in this area? Or perhaps it _has_ been done and that's why nearly everyone uses uranyl acetate? And perhaps coffee was tried decades ago and found to be generally inferior?
- BigTTYGothGF 10mo agoOf course it's been done, and there are lots of different stains available: https://www.agarscientific.com/general-consumables/chemicals/stains-for-em https://www.agarscientific.com/general-consumables/chemicals...
- buildbot 10mo agoWow you know it’s a fun party when the first result needs to specify it’s _not_ radioactive Oh I see - Uranyl Acetate is radioactive and this replaces it. Fun! This seems like a friendly chemical too - “ The chemical properties of Osmium Tetroxide are such that use and handling of the chemical is often considered daunting. Although its volatility and toxicity certainly makes it a dangerous chemical, but when following the proper procedure and taking the necessary precautions, Osmium Tetroxide can be used to its full potential with limited risk to the user. This is more toxic than glutaraldehyde and has a higher vapour pressure. Particular care must be taken to avoid breathing the vapour or allowing it to affect the eyes. ”
- s0rce 10mo agoUranyl acetate for staining is typically depleted and unless you have regulatory issues I don't think the radiation is a big concern, especially when you compare to the very serious toxicity of OsO4 (vapors can react with your eyes and blind you).
- 9mo ago
- Rastonbury 10mo agoI'm reminded of how blacksmiths use instant coffee to stain damascus steel, at least the ones on YouTube
- peacebeard 9mo agoDoes that last long? Commercial damascus is typically acid etched which seems like it would last better, but it wears off eventually too. [edit] oh, I guess coffee is acidic, so maybe it’s not that different. I was thinking of using it as a stain at first
- s0rce 10mo agoI don't really understand how coffee, lacking heavy metals, can effectively give contrast in the electron microscope. I can't access the paper but the available parts didn't seem to explain how this works.
- seesawtron 9mo agoEven without any heavy metal staining, you would end up seeing some structures. This approach allows looking at unstained / native tissue.
- s0rce 9mo agoWhat is the coffee doing?
- ravila4 10mo agoOne of the references: “Oolong tea extract as a substitute for uranyl acetate in staining of ultrathin sections”