Cost-effective media for the rapid and high resolution of small DNA fragments using polyacrylamide-based electrophoresis

Current Tris-based solutions for DNA electrophoresis produce a positive feedback loop between current and temperature at high voltage, resulting in long running times for the separation of even small DNA fragments. We optimized the separation of small DNA fragments (90-300 bp) in polyacrylamide-based electrophoresis at high voltages (200volts/cm) by substituting Tris with low concentration alkali salts (e.g. 1 mm LiCl and CsCl). These media reduced the heat produced during electrophoresis, enhanced the DNA fragment resolution, and allowed gels to be run at higher voltages, reducing gel running times by 25%. In addition, the elimination of Tris and EDTA from the buffer reduced material costs approximately 10-fold.