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Does dish soap emulsify lipids in the cell membrane?

  1. Nov 20, 2004 #1
    http://www.google.ca/search?q=cache:0j8NdYaQ3L4J:www.foodsafetynetwork.ca/biotechres/activityextraction.pdf+Kiwi+DNA+Extraction+Lab&hl=en [Broken]

    The above url is a lab that states that to do a DNA extraction of kiwi the cell membrane is eliminated through liquid detergent and mechincal mashing - done with a beaker in hot water. Would I be correct in saying the liquid detergent emulsifies the lipids in the cell membrane causing it to break down and be more easily destroyed through mechanical mashing?

    Does the liquid detergent activate immediately or does heat have to cause movement in order for the emulsifying to occur?

    Last edited by a moderator: May 1, 2017
  2. jcsd
  3. Nov 20, 2004 #2


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    Yes, it emulsifies the membrane. Here's a site that explains the actions of a number of reagents used to break down membranes for DNA extraction:
    http://dwb.unl.edu/Teacher/NSF/C08/C08Links/cpmcnet.columbia.edu/dept/physio/tchrplan/oniondna.html [Broken]

    The detergent will act without heat. There are a number of biological grade detergents available, such as SDS, Triton-X100, Tween, and Saponin, that have different strengths as detergents. You can use them in very low concentrations just to make the membrane more permeable, such as to get in antibodies for immunocytochemistry, or you can use higher concentrations to break down the membrane to extract the DNA.

    Because detergent will break down cell membranes, we have to be VERY careful in the lab to make sure all detergent residue is fully rinsed off glassware before using it.
    Last edited by a moderator: May 1, 2017
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