Patent ID: 8409848

Claim:
An apparatus for use in carrying out a reaction by thermal cycling, comprising: a microfluidic chip; a microfluidic channel formed in the microfluidic chip, the microfluidic channel having at least one wall; an electromagnetic energy source configured and arranged to output radiation such that the radiation illuminates at least a portion of the microfluidic channel; an energy absorption element which is present in or on one or more walls of the microfluidic channel or which is present in a sample within the microfluidic channel; wherein, the energy absorption element is configured to absorb at least a portion of the radiation, and, thus, heat when illuminated by the radiation, wherein the absorption element is positioned such that when the absorption element is heated by the radiation the absorption element transfers heat to a sample that is in the microfluidic channel; and a heat-exchange channel having a generally U-shaped cross section and containing a heat exchange fluid, wherein the heat-exchange channel is located below the microfluidic channel and wherein the heat-exchange channel is configured to allow both introduction and removal of a heat exchange fluid to facilitate thermal cycling in the microfluidic channel.