Thermal Cycler for Automatic Performance of the Polymerase Chain Reaction with Close Temperature Control

Abstract

A thermal cycler for automatic performance of the polymerase chain reaction is provided. The thermal cycler comprises a heater control that provides close temperature control of the reaction.

1 . A thermocycler apparatus comprising: 
 at least one sample well capable of receiving a sealed vessel containing a liquid sample mixture;    a cover configured to contact the top of a sealed vessel in the at least one sample well;    a heater configured to heat said cover; and    a heater control adapted to control the heater so that the cover keeps an upper part of a sealed vessel disposed in the sample well at a temperature from 94° C. to 110° C. during an entire PCR cycle such that condensation and refluxing of such liquid sample in the sealed vessel is avoided.    
     
     
         2 . The thermocycler apparatus of  claim 1 , further comprising a sealed vessel disposed in the at least one sample well.  
     
     
         3 . The thermocycler apparatus of  claim 2 , further comprising a liquid sample disposed in the sealed vessel.  
     
     
         4 . The thermocycler apparatus of  claim 2 , further comprising ingredients for polymerase chain reaction disposed in the sealed vessel.  
     
     
         5 . The thermocycler apparatus of  claim 1 , wherein the at least one sample well is formed in a sample block.  
     
     
         6 . The thermocycler apparatus of  claim 1 , further comprising means for forcing the cover against the top of a sealed vessel disposed in the at least one sample well.  
     
     
         7 . The thermocycler apparatus of  claim 6 , wherein the at least one sample well comprises a plurality of sample wells, the apparatus further comprises a plurality of sealed vessels respectively disposed in the plurality of sample wells, and the means for forcing the cover against the top of a sealed vessel is adapted to press each sealed vessel of the plurality of sealed vessels firmly into its respective sample well.  
     
     
         8 . The thermocycler apparatus of  claim 7 , wherein the plurality of sealed vessels comprises a microtiter plate format.  
     
     
         9 . The thermocycler apparatus of  claim 7 , wherein the plurality of sealed vessels comprises a plurality of sample tubes, each sample tube comprises a cap, and the means for forcing the cover against the top of a sealed vessel is adapted to deform the cap of each sample tube and press each sample tube into its respective sample well.  
     
     
         10 . The thermocycler apparatus of  claim 1 , wherein the heater control is adapted to control the heater so that the cover is kept at a temperature of from 100° C. to 110° C.  
     
     
         11 . A thermocycler apparatus comprising: 
 at least one sample well capable of receiving a sealed vessel containing a liquid sample mixture;    a cover configured to contact the top of a sealed vessel in the at least one sample well;    a heater configured to heat said cover; and    a heater control adapted to control the heater so that the cover is heated to a temperature above the boiling point of water during an entire PCR cycle such that condensation and refluxing of such liquid sample in the sealed vessel is avoided.    
     
     
         12 . The thermocycler apparatus of  claim 11 , further comprising a sealed vessel disposed in the at least one sample well.  
     
     
         13 . The thermocycler apparatus of  claim 12 , further comprising a liquid sample disposed in the sealed vessel.  
     
     
         14 . The thermocycler apparatus of  claim 12 , further comprising ingredients for polymerase chain reaction disposed in the sealed vessel.  
     
     
         15 . The thermocycler apparatus of  claim 11 , wherein the at least one sample well is formed in a sample block.  
     
     
         16 . The thermocycler apparatus of  claim 11 , further comprising a screw for forcing the cover against the top of a sealed vessel disposed in the at least one sample well.  
     
     
         17 . The thermocycler apparatus of  claim 16 , wherein the at least one sample well comprises a plurality of sample wells, the apparatus further comprises a plurality of sealed vessels respectively disposed in the plurality of sample wells, and the screw for forcing the cover against the top of a sealed vessel is adapted to press each sealed vessel of the plurality of sealed vessels firmly into its respective sample well.  
     
     
         18 . The thermocycler apparatus of  claim 17 , wherein the plurality of sealed vessels comprises a microtiter plate format.  
     
     
         19 . The thermocycler apparatus of  claim 17 , wherein the plurality of sealed vessels comprises a plurality of sample tubes, each sample tube comprises a cap, and the screw for forcing the cover against the top of a sealed vessel is adapted to deform the cap of each sample tube and press each sample tube into its respective sample well.  
     
     
         20 . A method for thermocycling a liquid sample mixture in a sealed vessel, the method comprising: 
 positioning at least one sealed vessel into at least one sample well, each sealed vessel of the at least one sealed vessel comprising inside surfaces and an upper part, and containing a polymerase chain reaction sample mixture having a concentration, wherein the polymerase chain reaction mixture comprises DNA and at least two primers complementary to the DNA to create extension products of the DNA;    lowering a cover into contact with the upper part of each sealed vessel of the at least one sealed vessel;    thermocycling the liquid sample mixture in each sealed vessel using a first heater that is in thermal contact with the at least one sample well, through many polymerase chain reaction cycles; and    heating the upper part of each sealed vessel with a second heater that is different than the first heater and that is in thermal contact with the upper part of each sealed vessel, during the many polymerase chain reaction cycles so that condensation and evaporation of the polymerase chain reaction sample mixture within the sealed vessel is avoided during the many polymerase chain reaction cycles and the polymerase chain reaction sample mixture concentration is controlled through the many polymerase chain reaction cycles.    
     
     
         21 . The method of  claim 20 , wherein the at least one sealed vessel comprises a plurality of sealed vessels, the at least one sample well comprises a plurality of sample wells, and the method comprises placing the plurality of sealed vessels in the plurality of sample wells.  
     
     
         22 . The method of  claim 21 , wherein the plurality of sealed vessels comprises a plurality of sample tubes and each of the sample tubes comprises a cap.  
     
     
         23 . The method of  claim 21 , wherein the plurality of sealed vessels comprises a plurality of sample tubes, each sample well of the plurality of sample wells comprises an inside surface, and the method comprises snugly contacting a lower portion of each sample tube with the respective inside surface of the sample well that contains the lower portion.  
     
     
         24 . The method of  claim 21 , wherein the plurality of sealed vessels comprises a microtiter plate format.  
     
     
         25 . The method of  claim 20 , wherein the many polymerase chain reaction cycles comprises 25 to 30 cycles.  
     
     
         26 . The method of  claim 20 , wherein the at least one sealed vessel comprises a cap.  
     
     
         27 . The method of  claim 26 , wherein the method further comprises deforming the cap.  
     
     
         28 . The method of  claim 20 , further comprising heating the cover so that the cover is kept at a temperature of from 94° C. to 110° C. during the many polymerase chain reaction cycles.