AN IMPROVED PROTOCOL TO INCREASE SENSITIVITY OF SOUTHERN BLOT USING DIG-LABELED DNA PROBES

The use of methods for nonradioactive labelling of nucleic acids has i ncreased in recent years because they avoid disadvantages associated w ith radioisotopes. The most frequently used label is digoxigenin (DIG) . The greatest problem of nonradioactive methods is their high nonspec ific background mainly caused by the multistep detection. A diffuse ba ckground can mask the specific signal; furthermore nonspecific signals can make it difficult to interpret the result. In this study we have attempted to identify elements which could generate background. We hav e also determined the probe and antibody concentrations by which the h igher sensitivity is obtained. (C) 1997 Elsevier Science B.V.