Coated Substrate for Biological Reaction Systems

Abstract

An apparatus for biological reactions is provided. The apparatus includes a substrate and a plurality of reaction sites within the substrate. A surface of the substrate is configured to have a first hydrophilicity and each surface of the plurality of reaction sites is configured to have a second hydrophilicity to load a substantial number of reaction sites with a sample volume. The sample volume of each loaded reaction site is substantially confined to its respective reaction site. The sample volume is configured to undergo a biological reaction within the reaction site.

What is claimed is: 
     
         1 . A method for designing a substrate with a plurality of reaction sites, the method comprising:
 determining an advancing water contact angle of a liquid sample with a coating material;   determining a water contact angle for the liquid sample with the coating material; and   if the water contact angle is within 15 degrees of the advancing water contact angle, coating a surface of the substrate and a surface of each reaction site of the plurality of reaction sites with the coating material.   
     
     
         2 . The method of  claim 1 , wherein the advancing water contact angle is 70-85 degrees. 
     
     
         3 . The method of  claim 1 , wherein the water contact angle is 60-100 degrees. 
     
     
         4 . The method of  claim 1 , wherein the coating material configures the surface of the substrate and the surface of each of the reaction site to have the same hydrophilicity. 
     
     
         5 . The method of  claim 1 , wherein the coating material is hexamethyldisilazane (HMDS). 
     
     
         6 . The method of  claim 1 , wherein the surface of the substrate and the surface of each reaction site is coated by a vapor deposition process. 
     
     
         7 . The method of  claim 1 , wherein the coating material results in a hydrophilicity to generate a sufficient surface tension force to substantially confine the liquid sample within each loaded reaction site. 
     
     
         8 . The method of  claim 1 , wherein a dimension of each reaction site is selected based on a volume of sample loaded into each reaction site by capillary action. 
     
     
         9 . The method of  claim 1 , wherein the substrate with the plurality of reaction sites is configured for undergoing an amplification reaction of the liquid sample. 
     
     
         10 . The method of  claim 1 , wherein the advancing water contact angle and the water contact angle facilitates loading of the liquid sample into the plurality of reaction sites. 
     
     
         11 . The method of  claim 1 , wherein the advancing water contact angle and the water contact angle minimizes pooling of the liquid sample on the substrate. 
     
     
         12 . The method of  claim 1 , wherein the coating material minimizes adsorption of biological reaction chemicals and components. 
     
     
         13 . The method of  claim 1 , wherein the coating material is biocompatible. 
     
     
         14 . The method of  claim 1 , further comprising:
 selecting a geometry of the plurality of reaction sites to provide sufficient surface tension to substantially confine the liquid sample within each loaded reaction site.   
     
     
         15 . The method of  claim 14 , wherein the selected geometry of the plurality of reaction sites minimizes cross-talk between the plurality of reaction sites. 
     
     
         16 . The method of  claim 1 , wherein the surface of the substrate and the surface of each reaction site is by a liquid coating process. 
     
     
         17 . The method of  claim 15 , wherein the selected geometry is a hexagonal shape.