October 24th, 2007

Sharpies

Sterile Lab supplies Question

My labmate is ridiculously careful while I can be kind of lax, so I never know when his protocol is way over the top or if what he's saying is reasonable.
So two situations:
1) He won't use a shrink wrapped box of sterile(as said by the company)tips without autoclaving it first if he thinks there's any chance anyone's touched it with out gloves, even if the shrink wrap is completely intact. As long as the packaging doesn't look compromised, I figure what's inside the box is the most important and wipe down the outside with an appropriate cleaner (ethanol, RNAse away)
2) He claims things left in an autoclave over night are no longer sterile. Have people heard of this? Why would this be true? Again I figure as long as no one's handled the stuff or it's been opened or compromised in any other way it should be ok.

For reference, we have sterile for tissue culture, RNase free, and things that need to be both.
No clean or positive pressure rooms. We're BL2 and work with primary culture and cell lines, very rarely in vivo stuff.