US Patent 7459302 Side-wall heater for thermocycler device

The invention relates to an apparatus and methods for preventing condensation on the interior surfaces of sample tubes which are being exposed to temperature cycles, such as during a PCR amplification reaction. In particular, the invention relates to apparatus comprising a sample block comprising a plurality of sample wells for receiving sample tubes and heating elements disposed in the sample wells for heating at least a portion of the sides of sample tubes (e.g., at least the portion which forms the head space after a tube is filled with a PCR reaction mixture). In a preferred aspect, the sample block is part of a thermocycling device for performing PCR and the side-wall heater is used to enhance uniformity and speed of amplification reactions. For example, by decreasing or eliminating condensation, signal strength jumps in a real-time PCR assay can be minimized as can reaction non-homogeneity.