Payback's... to be expected.

You may recall my agonizing a couple weeks ago over destroying some cells for an experiment.

This week, I was showing my labmate some crystals I had growing.  The tray slips an inch in his hand and water splashes to the cover slip, washing off the best candidate I had.  Se la vie.

At least he's guilted into showing me how to run high throughput trays tomorrow.

Back to basics. Water.

Today I planned to do a titration curve with my protein and check some ph points for future experiments.

I took a baseline with the NANOPure (tm) water just to see how the pH meter worked. Apparently our water is pH 5.8 +- 0.3 pH units, depending on the mood of the pH meter. But wait, turn off the stir bar and it shoots up 0.5 units. And if you use litmus paper, it's pH 4.7.

So I can't trust the paper or the meter or the water. No one knows the last time the machine was checked (years), but it should be every 6 months.

Here's hoping I don't have bad news for everyone tomorrow.

Update: a bit of reading reveals that our water is probably good. Dissolved CO2 hits exactly 5.8. The high resistance of pure water (no ions) makes pH meters freak out. I'm not sure yet what is up with the litmus paper. Need to get a direct resistance reading off the machine (should be above 18Mohms I believe). See if there are other tests to do. Or just a technician.

http://www.millipore.com/references/files/pmc_url/$file/highpuritywater.pdf

Destroying other people's projects

One of my lab's soon-to-be-alumni came back in town this weekend to do one more experiment.  I was prepping some cells for her in what should have been a simple procedure.  Of course, I'd never done it before (like most things) and had gotten a 10 minute explanation the last time she was here about what I'd have to do. The experiment itself is about 15 minutes of prep followed by 2.5 hours of sonication, then 10 minutes of post.

Of course, I messed it up. Everything was great except I forgot to turn on the chiller to the sonicator. Come back two hours later and the cells are cooked to a sterile 60C+.  There was condensation everywhere and things were nearly too hot to touch. Since we're not exactly engaged in protein folding, there wasn't much useful left of the cells. I flash froze them anyway just in case.  (Also to play with liquid nitrogen (sssshhhh)).

I tried to acquire new stocks from our partner lab, but the best they could do is start growing new stocks, which won't be ready till next week. So lab mate gets a vacation this weekend instead of working.  I don't think she was particularly disappointed by this turn of events, because now someone else gets to do her experiment for her.

This kind of thing actually happens all the time, but this was my first time in this lab.  Usually you screw something up yourself, at least until you have enough experience or have good "lab hands".  This particular incident was more unfortunate since she had flown in, but even having blown away $300 in tickets and cell preps, everyone pretty well blew it off.  Just have to try again next week.