17 June 2013

From 2013.igem.org

Today, we assisted Madina (one of our advisors) to do the SELEX cycle 8 (selecting aptamers against CEA) and to finish cycle 3 of SELEX (selecting aptamers against ECPKA). For SELEX cycle 3 we have finished with precipitation of DNA aptamers and have put them store at -20degC, to use it in SELEX 4. For SELEX 8 we did the following steps:
  1. Denaturation of dsDNA from SELEX 7
  2. Pre-wetted (passing DNAs through pre-wetted nitrocellulose membrane)
  3. Binding (incubating denatured DNA with the target protein CEA)
  4. Washing (passing binding reaction mixture through the membrane using washing buffer)
  5. Elution is done to degrade protein, and to remove it from DNA
  6. Precipitation (eluted DNA was diluted with water, and then 100% ethanol, ammonium acetate and glycogen were added). The mixture was incubated at -80degC for one hour. After that, precipitation was done.
  7. PCR to make dsDNA
  8. We checked PCR product with 6% TBE gel.
See the detailed procedure in our protocol.