Repurposing beads in sample cleanup

Abstract

The present invention provides methods for repurposing beads and other solid supports for separately capturing RNA and DNA without a loss of binding capacity by using a surfactant.

1 . A method for capturing RNA and DNA using a solid support, the method comprising:
 capturing mRNA on a solid support coated with an oligo dT in a low ionic strength buffer;   releasing the captured mRNA; and   adding surfactant, salt and a crowding agent then capturing DNA on the solid support.   
     
     
         2 . The method of  claim 1 , wherein the surfactant is sodium dodecyl sulfate (SDS). 
     
     
         3 . The method of  claim 2 , wherein the solid support is a bead. 
     
     
         4 . The method of  claim 3 , wherein the bead is a magnetic bead. 
     
     
         5 . The method of  claim 1 , further comprising the step of synthesizing cDNA from the released mRNA. 
     
     
         6 . The method of  claim 5 , wherein the captured DNA is cDNA synthesized from the mRNA. 
     
     
         7 . The method of  claim 6 , further comprising the step of sequencing the DNA. 
     
     
         8 . The method of  claim 7 , wherein the method is performed automatically by a device without user input. 
     
     
         9 . A method for capturing nucleic acids on a solid support, the method comprising repeatedly capturing and releasing nucleic acids on a solid support without denaturing or removing proteins between captures; 
     
     
         10 . The method of  claim 9 , further comprising introducing surfactant to a sample comprising the nucleic acids before capture. 
     
     
         11 . The method of  claim 10 , wherein the surfactant is sodium dodecyl sulfate (SDS). 
     
     
         12 . The method of  claim 9 , wherein the solid support is a bead. 
     
     
         13 . The method of  claim 12 , wherein the bead is a magnetic bead. 
     
     
         14 . The method of  claim 9  wherein the nucleic acids comprise mRNA and cDNA. 
     
     
         15 . The method of  claim 10  wherein the cDNA is synthesized from the mRNA between captures.