Capillary electrophoresis of DNA in agarose solutions at 40 degrees C

DNA fragments ranging from 72 to 1353 bp in length (phi X174 RF DNA/HaeIII) were separated by capillary electrophoresis in 0.3-2.0% solutions of agarose (Sea-Plaque GTG) at 40 degrees C. Liquified agarose above its gelling temperature is easily filled and refilled into capillaries. Its background absorbance at 260 nm was sufficiently low to allow for DNA detection at an estimated DNA load of 13 ng/10 components. Sample injection proceeded at 1 kV for 16 s. The internal capillary diameter was 150 mu, the migration path 27 cm. Migration times varied from 5 to 14 min at 185 V/cm. Potentially, the applicability of capillary electrophoresis in agarose solutions can be expected to extend to the entire size range of DNA, in view of the recent demonstration of kb-sized circular DNA separations in agarose solutions, and those of Mb-sized DNA-agarose complexes in linear polyacrylamide solutions.