For a bigger commensurable potential range we used directly heatable bismuth electrodes. With these electrodes it was possible to measure in a more negative potential. We could detect a very small amount of organic molecules like the picric acid just because of this higher potential range of these electrodes and because of elevated temperatures at these electrodes. Furthermore we could detect hybridization reactions on heated gold electrodes. We used targed strands labeled with the complex [OsO4(bipy] for the labeling the targets and detect them on immobilized probes. It was possible to label DNA and RNA-strands. The use of higher temperatures enabled the separation of complementary DNA-targets and targets containing mismatches.