maradydd: (Default)
maradydd ([personal profile] maradydd) wrote2008-12-26 09:52 pm
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[PSA] Biohacking FAQs #3, #4, #5

3. Gel electrophoresis uses ethidium bromide, which is a dangerous chemical. How are you disposing of it safely?

I'm not using ethidium bromide. There are a number of other gel stains which are much safer and easier to work with, such as SYBR-Green and SYBR-Safe. I use GR Safe, which is similar to SYBR stains but even better, because it can be stored at room temperature.

Per standard biosafety practices, I sterilize everything before I dispose of it.

4. Why is there toilet paper sitting on your lab table?

It's absorbent and good for wiping up spills, and it wastes less paper than using full paper towels to wipe up the occasional spill of less than 2mL of liquid. (The paper towels weren't in the frame. Nor was the sharps bin, or the fire extinguisher, or any other safety equipment. It's all within reach, though.)

5. Why are there Ziploc bags sitting on your lab table?

The bacteria I work with -- Lactobacillus acidophilus, Lactobacillus bulgaricus and Streptococcus thermophilus -- are what's called "facultative anaerobes": they prefer environments where there isn't much oxygen. (They'll grow when there's O2 around, but they won't grow as quickly.) So, when I plate them on a petri dish, I put the finished plate in a Ziploc bag. Then I put some vinegar and baking soda into an empty Coke bottle and capture the generated CO2 gas in a balloon, squirt the gas into the Ziploc bag, and close it up.

I asked a former boss of mine (a bioinformaticist whose PhD is in population genetics) whether he had any ideas for easy ways to provide an oxygen-free environment for my plates, and he said they used the same Ziploc bag trick when he was in grad school. It's ghetto, but hey, it works.

[identity profile] kejlina.livejournal.com 2008-12-27 04:26 pm (UTC)(link)
I thought it was a little weird that people in various comments threads were getting so hung up on ethidium bromide. I mean, if someone knows enough about electrophoresis to know what ethidium bromide is and how dangerous it is, they should also know that there's different types of electrophoresis and different dyes available, right?

[identity profile] maradydd.livejournal.com 2008-12-27 06:45 pm (UTC)(link)
Yeah, that had me kind of baffled too. I suppose a picture of the electrophoresis chamber might have helped, though I wonder whether the people flipping out about the dangers of polyacrylamide actually know that PAGE is run vertically and agarose horizontally...

[identity profile] bigby.livejournal.com 2008-12-28 04:05 am (UTC)(link)
This could be a Wiki-knowledge vs real knowledge issue.

[identity profile] maradydd.livejournal.com 2008-12-29 11:13 am (UTC)(link)
Ah, good point. I do love Wikipedia, but you're right that it often doesn't give the full picture.