amethyst73 | *blink* Wow.

I have just received a protocol from another lab, which involves transferring materials from one 96-well block to another. (For non-wetlab types, these are blocks with 96 tiny little bowls in it, in which the 'bowls' - or, more properly, wells - are arrayed in a 12x8 grid.) There's a neat gadget called a multiwell pipettor that allows you to pick up a set volume from 8 or 12 of these wells at the same time, for dispensing into a second block.

I kid you not, here's what the protocol says about transferring the stuff from one block to another.
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Pipette first column/row.
DISCARD tips.
Pipette second column/row.
DISCARD tips.
Etc…
Until plate is complete.
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Um. Duh. If you don't change tips between rows, then you're going to contaminate later wells with the little bits of liquid that always get left behind from the earlier rows. There are people who need to have this clarified???