When conducting the first experiments with NucleoLink Strips, it is important that the strips are closely observed for possible evaporation after thermal cycling.

Normally, evaporation will cause a lack in reproducibility in both DIAPOPS and liquid phase PCR results, and for this reason the first thing to do when reproducibility problems occur is to control the amount of liquid left in the wells after thermal cycling. Only after it has been established that there is no problem with evaporation, should the other options mentioned in the trouble shooting table ( ) be taken into consideration.

The following factors in the thermal cycler may cause evaporation:

• Improper tightening of the heated lid on thermal cycler before thermal cycling program
• Using a thermal cycler which cannot apply pressure to the NucleoLink Strips
• Using a thermal cycler which gives uneven pressure on the NucleoLink Strips
• Using a thermal cycler without heated lid

When it has been established that the thermal cycler fits the NucleoLink Strips and no evaporation occurs in the first experiments, there should be no problem. However, in the routine use of NucleoLink Strips evaporation from a few or from all the wells can occur arising from of one of the following factors:

• Not applying Tape 8 before placing the NucleoLink strips into the thermocycler
• Tape 8 is not covering the whole opening of all wells in one or several strips
• Omitting to place the silicone pad over the NucleoLink strips in the thermal cycler
• A previously used silicone pad is attached to the heated lid of the thermocycler. A new pad is also placed on the NucleoLink Strips, and the old pad does not cover the new pad entirely. Pressure is therefore not even on all wells