Thermal cycling apparatus and method for providing thermal uniformity

Abstract

An apparatus and method for rapid thermal cycling including a thermal diffusivity plate. The thermal diffusivity plate can provide substantial temperature uniformity throughout the thermal block assembly during thermal cycling by a thermoelectric module. An edge heater can provide substantial temperature uniformity throughout the thermal block assembly during thermal cycling.

What is claimed is:  
     
         1 . An apparatus for thermally cycling biological sample comprising: 
 a thermal block assembly for receiving said biological sample;    a thermoelectric module coupled to said thermal block assembly; and    a heat sink, wherein said heat sink is coupled to said thermoelectric module, wherein said heat sink comprises a base plate, fins, and a thermal diffusivity plate, and wherein said thermal diffusivity plate comprises a different material than said base plate and fins,    wherein said thermal diffusivity plate provides substantial temperature uniformity to said thermal block assembly during thermal cycling.    
     
     
         2 . The apparatus of  claim 1 , wherein said thermal diffusivity plate is positioned to couple to said thermoelectric module.  
     
     
         3 . The apparatus of  claim 1 , wherein said thermal diffusivity plate comprises at least one of copper, silver, gold, and silicone carbide.  
     
     
         4 . The apparatus of  claim 1 , wherein said thermal block assembly comprises at least one of silver, gold, aluminum, silicone carbide, and magnesium.  
     
     
         5 . The apparatus of  claim 1 , wherein said base plate and fins comprise aluminum.  
     
     
         6 . The apparatus of  claim 5 , wherein said fins are arranged in a pin fin configuration.  
     
     
         7 . The apparatus of  claim 5 , wherein said fins are arranged in a swage fin configuration.  
     
     
         8 . The apparatus of  claim 1 , wherein said thermoelectric module comprises a thermoelectric gap, wherein said thermoelectric gap is reduced to provide substantial temperature uniformity throughout said thermal block assembly.  
     
     
         9 . The apparatus of  claim 8 , wherein said thermoelectric gap is reduced to less than 5 millimeters.  
     
     
         10 . The apparatus of  claim 1 , further comprising an edge heater, wherein said edge heater is coupled to the perimeter of said thermal block assembly.  
     
     
         11 . The apparatus of  claim 1 , wherein said apparatus provides a PCR cycle time of less than thirty seconds.  
     
     
         12 . An apparatus for thermally cycling biological samples comprising: 
 a thermal block assembly for receiving said biological samples;    a thermoelectric module coupled to said thermal block assembly;    a heat sink; and    a thermal diffusivity plate coupled to said thermoelectric module and said heat sink, wherein said thermal diffusivity plate is positioned between said thermoelectric module and said heat sink,    wherein said thermal diffusivity plate has a significantly greater thermal diffusivity than said heat sink.    
     
     
         13 . The apparatus of  claim 12 , wherein said thermal diffusivity plate provides substantial temperature uniformity to said thermal block assembly during thermal cycling.  
     
     
         14 . The apparatus of  claim 13 , wherein said substantial temperature uniformity provides cooling of at least 10° C. in at most ten seconds for said thermal block assembly.  
     
     
         15 . The apparatus of  claim 12 , wherein said thermal diffusivity plate comprises copper.  
     
     
         16 . The apparatus of  claim 15 , wherein said thermal block assembly comprises silver and gold.  
     
     
         17 . The apparatus of  claim 16 , wherein said heat sink comprises a base plate and fins, wherein said fins are arranged in at least one of a pin fin configuration and a swage fin configuration.  
     
     
         18 . The apparatus of  claim 17 , wherein said thermoelectric module comprises a thermoelectric gap, wherein said thermoelectric gap is reduced to provide substantial temperature uniformity throughout said thermal block assembly.  
     
     
         19 . The apparatus of  claim 18 , wherein said thermoelectric gap is reduced to less than 5 millimeters.  
     
     
         20 . The apparatus of  claim 12 , further comprising an edge heater, wherein said edge heater is coupled to the perimeter of said thermal block assembly.  
     
     
         21 . A method for thermally cycling biological sample comprising: 
 contacting a thermoelectric module to a thermal block assembly;    heating said thermal block assembly, wherein said thermal block assembly is adapted for receiving said biological sample; and    cooling said thermal block assembly, wherein said cooling comprises diffusing heat to a heat sink through a thermal diffusivity plate.    
     
     
         22 . The method of  claim 21 , further comprising contacting said thermal block assembly with an edge heater, wherein the edge heater is coupled to the perimeter of said thermal block assembly.  
     
     
         23 . The method of  claim 22 , further comprising providing substantial temperature uniformity to said thermal block assembly.  
     
     
         24 . The method of  claim 23 , wherein said diffusing provides cooling of at least 10° C. in at most ten seconds for said thermal block assembly.  
     
     
         25 . The method of  claim 24 , wherein said heating and cooling provides a PCR cycle time of less than thirty seconds.  
     
     
         26 . The apparatus of  claim 1 , wherein said thermoelectric module comprises at least two power regions.  
     
     
         27 . The apparatus of  claim 1 , further comprising a seal positioned on top of said thermal block assembly.