Team Builds Viruses To Combat Harmful "Biofilms"

Scientists from MIT and Boston University are creating viruses that will wipe out "biofilms" that contain harmful bacteria on surfaces of the human body and industrial or medical devices. "Bacterial biofilms can form almost anywhere, even on your teeth if you don't brush for a day or two. When they accumulate in hard to reach places such as the insides of food processing machines or medical catheters, however, they become persistent sources of infection. These bacteria excrete a variety of proteins, polysaccharides, and nucleic acids that together with other accumulating materials form an extracellular matrix, or in Lu's words, a "slimy layer," that encases the bacteria. Traditional remedies such as antibiotics are not as effective on these bacterial biofilms as they are on free-floating bacteria. In some cases, antibiotics even encourage bacterial biofilms to form."

Comments

kind of related: bacteriocide strength

[smellsofbikes]

One of the things I found interesting when I was taking microbiology is the reason for 70% rubbing alcohol. More is always better, right? so they're just being cheap, giving us 70% rather than 95% concentration?
Actually, there's a good reason for it, which is similar to what the article discusses: the material on the outside, that can protect the bacteria underneath. Pure or near-pure alcohol is so strong it coagulates the bacteria and material on the outside, forming a mostly-impermeable protective layer over the underlying bacteria, whereas 70% concentration seems to be as lethal as possible while still allowing the alcohol ready access to the interior of the protective slime layer.

So if you're doctorin' someone up, well, don't, but if you DO, forego the everclear in favor of whiskey. (although in many locales, everclear is apparently restricted by law to 50% alcohol concentration.)

Interesting side-note: if the alcohol burns, it's over 45% concentrated/90 proof. I don't know of a quick way to detect if it's *under* some percentage, but I suppose you could pour two shots in a tumbler, add a shot of water, and try burning it, and if it does, you're probably pretty good.