McClean: EDTA (0.5M)
EDTA is a synthetic amino acid and an agent that contains a typically organic ligand that bonds to a central metal atom. Enzymes that synthesize or modify nucleic acids (like polymerases, ligases, kinases, or nucleases) depend on Mg2+. With EDTA, it can stop the reactions between the enzymes and nucleic acids. EDTA is also in many buffers that store DNA (like TE buffer) removes the metal cofactors.
- 186.1g disodium ethylenediamine tetraacetate •2H2 (Na2EDTA)
- 800mL of dH2O
- 50mL NaOH
- Step 1 - Measure out 186.1g of Na2EDTA into a tall graduated cylinder
- Step 2 - Add in 800mL of dH2O and stir vigorously on a magnetic stirrer with a stir bar
- Step 3 - Using glass electrode (?), identify the pH of the solution
- Step 4 - If the pH is not around 8.0, carefully add in NaOH to adjust the pH
- Step 5 - Bring the solution up to 1L and stir
- Step 6 - Dispense the solution into aliquots
- Step 7 - Sterilize by autoclaving
- If the pH of the solution is not adjusted to 8.0, EDTA will not dissolve.
- Store at room temperature
- For more chemical information, go to http://openwetware.org/wiki/EDTA
Please feel free to post comments, questions, or improvements to this protocol. Happy to have your input!
- List troubleshooting tips here.
- You can also link to FAQs/tips provided by other sources such as the manufacturer or other websites.
- Anecdotal observations that might be of use to others can also be posted here.
Promega Corporation. "Recipes for Common Laboratory Solutions" Promega: Technical Reference (2010) https://www.promega.com/~/media/files/resources/technical%20references/recipes%20for%20common%20lab%20solutions.pdf.
Department of Ecology and Evolutionary Biology-University of Michigan. "Recipe for Stock Solution" Genomic Diversity Laboratory http://www.lsa.umich.edu/gdl/forms/pdf/Recipes-Stock.pdf.
- Megan N McClean 14:01, 20 July 2011 (EDT)
or instead, discuss this protocol.