Recipes for DNA Buffers

From Robb Brumfield and Donna Dittmann, Louisiana State University

DMSO buffer (makes 1L): 200 ml DMSO, 500 ml 0.5M EDTA, 300 ml ddH20. Mix and add huge quantities of NaCl (it takes a lot to saturate the solution); after saturation pour liquid into vessel (leaving NaCl) and check pH (stays close to 8.0). To adequately preserve tissue use at least 3:1 solution:tissue dilution; use screw-cap Eppendorf/Nunc tubes with o-rings.

DMSO-0.5 % SDS Lysis Buffer: The USDA sometimes requests this buffer for shipment to certain institutions. To 97.5 ml of DMSO buffer solution add 2.5 ml of 20% SDS.

20% SDS: 200 g sodium lauryl dodecyl sulfate (wear mask); 500 g dH20; Stir vigorously 15 min.; stop stirring and let settle 10 min.; bring volume to 1L; stir briefly to mix; filter through nitrocellulose; store on shelf. Clean spills with 95% ETOH.

MSB-EDTA, pH 7.5 (200 mM; makes 1L): 400 ml 2.5X MSB (1L: 95.66g Mannitol, 59.9g Sucrose, 65 ml 2M Tris-HCL, ph 8.0), 400 ml 0.5M EDTA pH 8.0; adjust pH to 7.5 with conc. HCL, bring to volume with ddH20).

EDTA buffer (10% EDTA, 0.1% Thymol; makes 100 ml): 10 g K2EDTA, 0.1 g thymol dissolved in 100 ml ddH20 (Na2EDTA may be substituted for K2EDTA, but it is difficult to dissolve.

Queen’s Lysis Buffer (makes 100 ml of a 10X solution): 1.21g Tris; 0.58g NaCl, 3.73g K2EDTA, 10.0g N-Lauryl sarcosyl; bring to volume with Millipore-filtered ddH20; pH 7.5 if necessary; autoclave.