Methods and compositions for isolating nucleic acid

Abstract

The present invention relates to compositions and methods for isolating and purifying nucleic acid. In particular, the present invention relates to methods of isolating nucleic acid from cells for use in further analysis.

1 . A method for processing a blood sample, comprising:
 contacting a blood sample with a device comprising a sample collection membrane with a pore size configured to retain nucleic acid and allow lysed red blood cells to flow through;   treating the membrane with a buffer that causes lyses of red blood cells in the blood sample;   drying the membrane to provide a dried, treated membrane.   
     
     
         2 . The method of  claim 1 , wherein the treating comprises treating with a buffer that lyses red blood cells and leaves purified white blood cells or components thereof on the membrane. 
     
     
         3 . The method of  claim 1 , wherein said contacting comprises contacting a blood sample with a device comprising a sample collection membrane comprising a lying agent. 
     
     
         4 . The method of  claim 1 , further comprising mailing the dried membrane for further processing. 
     
     
         5 . The method of  claim 1 , wherein said treating retains nucleic acid from white blood cells on the membrane. 
     
     
         6 . The method of  claim 5 , wherein the nucleic acid is an RNA. 
     
     
         7 . The method of  claim 1 , wherein said contacting comprising contacting a device comprising the sample collection membrane that is in contact with a blotter material. 
     
     
         8 . A method for analysis of a blood sample, comprising:
 receiving a sample collection membrane with a pore size configured to retain nucleic acid and allow lysed red blood cells to flow through on which a blood sample was placed, treated with a buffer to cause lysis of red blood cells, and dried to form a dried sample; and   processing the dried sample on the sample collection membrane to detect the presence of a particular nucleic acid.   
     
     
         9 . The method of  claim 8 , wherein the receiving comprising receiving a sample collection membrane treated with buffer that lyses red blood cells and leaves purified white blood cells or components thereof on the membrane. 
     
     
         10 . The method of  claim 9 , wherein the receiving comprising receiving a sample collection membrane treated with buffer that lyses red blood cells and leaves nucleic acid from white blood cells on the membrane. 
     
     
         11 . The method of  claim 10 , wherein the nucleic acid is genomic DNA or an RNA. 
     
     
         12 . The method of  claim 11 , wherein the RNA is a viral RNA. 
     
     
         13 . The method of  claim 10 , wherein the processing comprises amplifying the nucleic acid. 
     
     
         14 . The method of  claim 13 , wherein the processing comprising placing at least a portion of the sample collection membrane with the dried sample in an amplification process.