Polypropylene vs Polystyrene

I sometimes feel like there is only one way to learn anything in lab:  the hard way.  A lot of little details in lab go unmentioned, yet can make or break an experiment, and you won’t know it until things either don’t work, or go horribly awry.  Losing a day and a half because you didn’t realize that all plastic is not created equal falls into the latter category.  Losing someone else’s day and a half is, well, infinitely worse.

The easiest way to avoid the scorn of the entire lab is to carefully check what everyone is currently using and just stick with one kind.  However, if that is not possible or, say, you already ordered polystyrene tubes for the lab when polypropylene is the preferred kind and no one can tell them apart, yikes.  Unsurprisingly, I learned this the hard way; a post-doc in the lab was horrified to open the centrifuge on maxipreps to find the conical bottomed tubes fractured and his samples all over the rotor.  It was a stupid mistake that I thought only I was capable of making, until a month later when a tech from a brand new lab stopped by to ask what kind of conical bottom tubes we used, and asked very specifically about maxipreps.  I laughed because I knew instantly what the problem was.  I explained how you could hold them up to the light to determine whether the plastic was clear or cloudy, but that’s hard to determine without the other kind of tube as a basis for comparison.  That’s when a hammer and the desire to destroy things comes in handy.