Size selection purification using a thermoplastic silica nanomaterial

Abstract

The present disclosure is directed to a method for purifying a sample containing nucleic acids to obtain isolated nucleic acids of a desired size range, either above a size cut-off, below a cut-off, or within a defined band of sizes, including: a) combining a nucleic acid-containing sample with a binding buffer to provide a binding mixture; b) contacting the binding mixture with a silica nanomembrane, wherein the silica nanomembrane adsorbs nucleic acids from the binding mixture within a desired size-range; and c) separating the bound nucleic acid from the remaining sample. Kits including a silica nanomembrane, a binding buffer and one or wash buffers are also provided herein.

We claim: 
     
         1 . A method for purifying a sample containing nucleic acids to obtain isolated nucleic acids of a desired size range comprising:
 a. combining a nucleic acid-containing sample with a binding buffer to provide a binding mixture;   b. contacting the binding mixture with a nanomembrane, wherein the nanomembrane binds nucleic acids in the binding mixture;   c. selecting the nucleic acids based on size prior to, during, or after binding the nucleic acids with the nanomembrane; and   d. separating the bound nucleic acids from the remaining sample.   
     
     
         2 . The method of  claim 1 , wherein step c) comprises washing the nanomembrane after nucleic acid binding to selectively remove nucleic acids of a specific size range. 
     
     
         3 . The method of  claim 1 , wherein step c) comprises selectively binding nucleic acids of a specific size range. 
     
     
         4 . The method of  claim 1 , wherein step c) comprises selectively eluting bound nucleic acids of a specific size range. 
     
     
         5 . The method of  claim 1 , wherein step c) comprises performing a size specific precipitation of nucleic acids prior to step a. 
     
     
         6 . The method of  claim 1 , wherein step c) comprises performing a size specific precipitation of nucleic acids during nucleic acid binding. 
     
     
         7 . The method of  claim 1 , wherein step c) comprises performing a size specific precipitation of nucleic acids after elution. 
     
     
         8 . The method of  claim 1 , wherein the nucleic acids of the desired size range are bound to the nanomembrane. 
     
     
         9 . The method of  claim 1 , wherein the nucleic acids of the desired size range are not bound to the nanomembrane. 
     
     
         10 . The method of  claim 2 , wherein the nanomembrane comprises a silica nanomembrane, and the method comprises:
 a. contacting a wash solution with the silica nanomembrane, and   b. removing the wash solution from contact with the silica nanomembrane.   
     
     
         11 . The method of  claim 1 , wherein the desired size range of nucleic acids comprises all sizes above a cutoff value. 
     
     
         12 . The method of  claim 1 , wherein the desired size range of nucleic acids comprises all sizes below a cutoff value. 
     
     
         13 . The method of  claim 1 , wherein the desired size range of nucleic acids is a size range band above a lower cutoff value and below an upper cutoff value. 
     
     
         14 . The method of  claim 1 , wherein nucleic acids of a specific size band are produced by two or more sequential purification steps. 
     
     
         15 . The method of  claim 1 , wherein step c) comprises two or more size selective steps used in combination or sequentially. 
     
     
         16 . The method of  claim 1 , wherein a first eluate comprising nucleic acid sizes above a cutoff value and a second eluate comprising nucleic acid sizes below a cutoff value are produced from a single nucleic acid-containing sample.