Sample Block Apparatus and Method for Maintaining a Microcard on a Sample Block

Abstract

A sample block apparatus for a thermal cycler is provided, which can be configured for use with a microcard containing a plurality of samples of biological material. The apparatus can comprise a sample block comprising an upper surface configured for resting a microcard thereon. The upper surface can include surface irregularities for defining spaces between the surface irregularities and a microcard that may be positioned thereon. The apparatus can include a vacuum source in fluid communication with the space between the surface irregularity and the microcard positioned thereon. The vacuum source can be configured to create a substantial vacuum in the spaces thereby imparting a force on the microcard to retain the microcard on the sample block upper surface. The sample block apparatus can also include a temperature control system operatively connected with the sample block to cycle the sample block according to a user-defined profile.

1 - 9 . (canceled) 
     
     
         10 . A sample block apparatus for a thermal cycler configured for use with a microcard containing a plurality of samples of biological material, comprising:
 a sample block comprising an upper surface configured for resting a microcard thereon, the upper surface including surface irregularities for defining spaces between the surface irregularities and a microcard that may be positioned thereon;   a vacuum source in fluid communication with the space between the surface irregularity and the microcard positioned thereon, the vacuum source being configured to create a substantial vacuum in the spaces thereby imparting a force on the microcard to retain the microcard on the sample block upper surface; and   a temperature control system operatively connected with the sample block to cycle the sample block according to a user-defined profile.   
     
     
         11 . The sample block apparatus of  claim 10 , wherein the surface irregularities on the upper surface of the sample block comprise channels. 
     
     
         12 . The sample block apparatus of  claim 11 , wherein the channels comprise a plurality of perpendicularly intersecting grooves on the upper surface of the sample block. 
     
     
         13 . The sample block apparatus of  claim 12 , wherein the grooves are positioned in such a manner that the grooves are not positioned immediately vertically below the chambers in the microcard. 
     
     
         14 . The sample block apparatus of  claim 11 , wherein the channels comprise a plurality of substantially parallel grooves on the upper surface of the sample block. 
     
     
         15 . The sample block apparatus of  claim 12 , wherein the grooves are positioned in such a manner that the channels are not positioned immediately vertically below the chambers in the microcard. 
     
     
         16 . The sample block apparatus of  claim 10 , wherein the surface irregularities on the upper surface of the sample block comprise rough surfaces. 
     
     
         17 . The sample block apparatus of  claim 11 , wherein the sample block further comprises a gasket positioned around an outer periphery of the sample block channels, the gasket configured to engage a bottom surface of the microcard when the microcard is positioned on the sample block. 
     
     
         18 . The sample block apparatus of  claim 17 , wherein the sample block further comprises a groove around the outer periphery of the channels, the gasket being positioned in the groove. 
     
     
         19 . The sample block apparatus of  claim 10 , wherein the user-defined profile of the temperature control system is defined by a sequence of times and temperatures comprising at least a first temperature maintained for a first period of time and a second temperature maintained for a second period of time, with said second temperature being higher than said first temperature, and said cycling comprising at least two repetitions of said sequence of time and temperatures. 
     
     
         20 . A method of maintaining a microcard on a sample block of a thermal cycling device, comprising:
 providing a sample block with a plurality of channels on an upper surface thereof;   providing a microcard containing at least one sample of biological material above the upper surface of the sample block so that a bottom surface of the microcard may contact the upper surface of the sample block;   imparting a vacuum on spaces defined by the channels on the upper surface of the sample block and the bottom surface of a microcard positioned adjacent to the upper surface of the sample block, the vacuum creating a force to urge the microcard against the upper surface of the sample block; and   thermally cycling the microcard through a sequence of times and temperatures comprising at least a first temperature maintained for a first period of time and a second temperature maintained for a second period of time, with said second temperature being higher than said first temperature.   
     
     
         21 . The method of  claim 20 , further comprising providing a gasket on an outer peripheral surface of the sample block, the gasket contacting and forming a substantial seal with the bottom surface of the microcard during thermal cycling of the microcard. 
     
     
         22 . The method of  claim 21 , further comprising, prior to imparting a vacuum, pressing downward on the microcard to press the microcard against the gasket. 
     
     
         23 . The method of  claim 22 , wherein the step of pressing downward on the microcard is performed by a microcard carrier in contact with the microcard. 
     
     
         24 . The method of  claim 20 , further comprising, simultaneously with the step of thermally cycling the microcard, detecting the optical characteristics of the at least one sample of biological material. 
     
     
         25 . The method of  claim 20 , wherein the step of thermally cycling the microcard includes controlling the temperature of the sample block by a temperature control system operatively connected to the sample block, the temperature being raised and lowered according to a user-defined profile. 
     
     
         26 . The method of  claim 20 , wherein the step of thermally cycling the microcard further comprises at least two repetitions of said sequence of times and temperatures. 
     
     
         27 . The method of  claim 20 , further comprising optically detecting the characteristics of the at least one sample of biological material. 
     
     
         28 . A thermal cycling apparatus, comprising:
 a base, with said base defining a void therein;   a vacuum port disposed for fluid communication with said void;   support features disposed adjacent said void on the base, with said support features including uppermost surface regions defining a common plane; and   a temperature control system configured for cycling at least one of the base and the support features through a sequence of times and temperatures comprising at least a first temperature maintained for a first period of time and a second temperature maintained for a second period of time, with said second temperature being higher than said first temperature and said cycling comprising at least two repetitions of said sequence of times and temperatures.   
     
     
         29 . The thermal cycling device of  claim 28 , further comprising an optical detection system configured for detecting characteristics of samples of biological material contained in the microcard.