DI water

From Protists

Types of Water

HPLC water = high performance liquid chromatography water This is the highest quality water we have in lab, but it has to be ordered through CRS. It is kept in the Flammables Cabinet, but don't mistake it with the large methanol and ethanol bottles. It should be autoclaved in clean, small glassware and then used for any small scale molecular work (DNA storage, diluting reagents, etc.). After autoclaving it can be aliquoted out into labeled 1.5mL microfuge tubes and frozen in the Lab Supply white box in the -20C freezer. Don't put in more than ~1mL since water expands when frozen and the lids will pop open if over-filled and the water will no longer be sterile if that happens.

DI water = distilled water This is the highest quality water that we can get out of our lab and should be used sparingly. All media and large-scale molecular work buffers should be made using this type of water. Follow instructions for Distilled Water Retrieval if the big carboy on the sink in the culture hood room runs low or out. We used to use the distilled water purified from RO water that runs through the Barnstead Mega-Pure System MP-160 water distiller using the Protocol for Making DI Water, but don't do this anymore because it wastes too much water.

RO water = reverse-osmosis water This water has been somewhat processed through the building filtration system (via a reverse-osmosis process) and it is sufficiently free from contaminants to use for dishwashing (live and fix sides of lab) and drinking (only from live sink). This is the water that comes out of the skinny gray spigots in the main sinks in the lab (not available in the culture room sink, so use the one that is used for drinking instead and carry water back over to culture room).

Tap water DO NOT use this water for making medias or buffers or drinking! It should only be used for cleaning up messes on the floor and initial rinses for washing glassware.