grease

["Stephen M. Soisson" <soissos@rockvax.rockefeller.edu>]

***  For details on how to be removed from this list visit the  ***
***    CCP4 home page http://www.dl.ac.uk/CCP/CCP4/main.html    ***

Hi everyone:

In John Kuriyan's lab, we almost exclusively use petrolatum for greasing
plates.  This is MUCH easier to squeeze out of a syringe than vacuum
grease, and effectively eliminates the development of Popeye arms. :^)

Petrolatum has the additional advantage of readily melting on a
hotplate, so you can melt a beaker full of the stuff, and suck it up
into 50 syringes in about 10 minutes.  Wait for it to cool and solidify,
and you're ready to go!  Greasing takes me about 3-4 minutes per plate.

Some in the lab melt the petrolatum and then use some sort of circular
applicator (we have some scintillation vials that are perfect) to dip
and apply to the rim of the plate.  Works OK, but I am not convinced its
any faster than by hand since you still must do each well individually..

We only use vacuum grease for temperatures above 20 degrees, or if we
intend to transport the trays directly to the synchrotron (which is very
rare).

Anyone else out there using petrolatum??

Steve Soisson