McClean: Dry Ice-Ethanol Bath

Overview

Dry Ice-Ethanol baths are used to rapidly cool solutions to below freezing temperatures. In the lab, we most often use this for the Bust n' Grab genomic DNA preparation protocol. This protocol was adapted from the protocol of the Malaysian Cocoa Board (no joke!). See references below.

Materials

• Ice bucket or similar
• Dry ice (available as pellets downstairs near the loading dock)
• 70% (v/v) Ethanol (see notes)

Procedure

1. Find a suitable container, such as an ice bucket, to hold the bath. Don't use something that will crack due to the extreme temperatures.
2. Add several pieces of dry ice to the bath (see Hint #1).
3. Carefully add the Ethanol Solution to the Dry Ice until it covers the Dry Ice in the bath (see Hint #3).
4. After the Ethanol has cooled down, the solution will "boil" more slowly. As the "boiling" slows, add more Ethanol and / or Dry Ice as necessary.

Notes

Please feel free to post comments, questions, or improvements to this protocol. Happy to have your input!

1. List troubleshooting tips here.
2. You can also link to FAQs/tips provided by other sources such as the manufacturer or other websites.
3. Anecdotal observations that might be of use to others can also be posted here.

• Megan N McClean 18:49, 29 June 2012 (EDT) You need to be careful when handling the dry ice and especially when the bath is boiling. Wear gloves when handling the dry ice, a lab coat, and goggles (to protect your eyes in case of splashing ethanol)
• Megan N McClean 18:49, 29 June 2012 (EDT)For general applications, use 70% (v/v) Ethanol, although other concentrations of ethanol can be used. We generally use 95% ethanol for the Bust n' Grab protocol.

Please sign your name to your note by adding '''*~~~~''': to the beginning of your tip.

References

Malaysian Cocoa Board Protocol

Contact

• Megan N McClean 14:01, 20 July 2011 (EDT)

or instead, discuss this protocol.