Compositions and methods for preserving rna in biological samples

Abstract

The present invention concerns methods and compositions to prepare biological samples to preserve the macromolecules in the samples. Embodiments of the invention concern the use of a soak solution that contains one or more water-miscible solvents. A sample is incubated with the soak solution to the point of saturation at a temperature above the melting temperature of the water-miscible solvent but below 0° C. The use of methods and compositions of the invention allow for subsequent preparation or analysis of the samples.

1 - 20 . (canceled) 
     
     
         21 . A soak solution comprising at least 60% of one or more water-miscible solvents having a melting temperature below about 0° C. and further comprising from at least 1% and up to 20% DMSO. 
     
     
         22 . The soak solution of  claim 21 , wherein the soak solution comprises at least 60% of one or more water-miscible solvents having a melting temperature below about −20° C. 
     
     
         23 . The soak solution of  claim 21 , wherein the soak solution comprises at least 90% of one or more water-miscible solvents having a melting temperature below about −20° C. 
     
     
         24 . The soak solution of  claim 21 , wherein the one or more water-miscible solvents have a melting temperature below −50° C. 
     
     
         25 . The soak solution of  claim 21 , wherein the one or more water-miscible solvents have a melting temperature below −70° C. 
     
     
         26 . The soak solution of  claim 21 , wherein the one or more water-miscible solvents have a melting temperature below −100° C. 
     
     
         27 . The soak solution of  claim 22 , wherein one or more of the water miscible solvents is an alcohol. 
     
     
         28 . The soak solution of  claim 27 , wherein the soak solution comprises ethanol. 
     
     
         29 . The soak solution of  claim 27 , wherein the soak solution comprises ethanol, methanol, and isopropanol. 
     
     
         30 . The soak solution of  claim 21 , further comprising a homogenization solution. 
     
     
         31 . The soak solution of  claim 30 , wherein the homogenization solution comprises a protein denaturant. 
     
     
         32 . The soak solution of  claim 31  wherein the protein denaturant comprises guanidinium. 
     
     
         33 . The soak solution of  claim 22 , wherein the soak solution comprises at least 70% of one or more water-miscible solvents. 
     
     
         34 . The soak solution of  claim 33 , wherein the soak solution comprises at least 80% of one or more water-miscible solvents. 
     
     
         35 . The soak solution of  claim 21 , wherein the soak solution contains at least two water-miscible solvents. 
     
     
         36 . The soak solution of  claim 35 , wherein the soak solution contains at least three water-miscible solvents. 
     
     
         37 . The soak solution of  claim 36 , wherein the soak solution contains at least four water-miscible solvents. 
     
     
         38 . A soak solution comprising at least 90% ethanol and further comprising 4%-5% DMSO. 
     
     
         39 . The soak solution of  claim 38 , wherein the soak solution is about 94%-95% ethanol and has a pH of about 5. 
     
     
         40 . A soak solution comprising about 89%-90% ethanol, about 4%-5% DMSO, 4%-5% of a combination of methanol and isopropanol, and has a pH of about 5.