Method and test kit for the separation, purification and recycling of long- and short-chain nucleic acids

Abstract

Long- and/or short-chain nucleic acids are separated, purified and recovered by binding the nucleic acid to a solid phase using a binding buffer, to obtain a bonded nucleic acid, and eluting of the bonded nucleic acid from the solid phase, wherein the binding buffer comprises at least one citric acid salt and at least one alcohol.

1 . A method for the separation, purification and recovery of a long- and/or short-chain nucleic acid, comprising:
 binding the nucleic acid to a solid phase by using a binding buffer, to obtain a bonded nucleic acid; and   eluting of the bonded nucleic acid from the solid phase;   wherein the binding buffer comprises at least one citric acid salt and at least one alcohol.   
   
   
       2 . The method according to  claim 1 , wherein the binding buffer does not comprise (i) a chaotropic salt, or (ii) a combination of a salt with a monovalent cation and a salt with a multivalent cation. 
   
   
       3 . The method according to  claim 1 , wherein the citric acid salt represents a salt with a singly positively charged cation. 
   
   
       4 . The method according to  claim 1 , wherein a hydrogen citrate or a dihydrogen citrate or a mixture thereof is introduced as citric acid salt. 
   
   
       5 . The method according to  claim 1 , wherein the citric acid salt is selected from the group consisting of di-ammonium hydrogen citrate, ammonium dihydrogen citrate, tri-sodium citrate, di-sodium hydrogen citrate, sodium hydrogen citrate, tri-potassium citrate, di-potassium hydrogen citrate, potassium hydrogen citrate and mixtures thereof. 
   
   
       6 . The method according to  claim 1 , wherein an alcohol concentration of the binding buffer is between 20%-90 wt. %. 
   
   
       7 . The method according to  claim 1 , wherein an alcohol concentration of the binding buffer is between 40%-70 wt. %. 
   
   
       8 . The method according to  claim 1 , wherein said alcohol is methanol, ethanol, propanol, isopropanol, ethylene glycol, polyethylene glycol, gycerin or mixtures thereof 
   
   
       9 . The method according to  claim 1 , wherein the ion strength of said binding buffer during said binding of said the nucleic acid to said solid phase is less than 100 mM. 
   
   
       10 . The method according to  claim 1 , wherein the ion strength of said binding buffer during said binding of said the nucleic acid to said solid phase is less than 50 mM. 
   
   
       11 . The method according to  claim 1 , wherein said solid phase is selected form the group consisting of a glass fibre material, a silica gel, a suspension of a mineral support, a functionalized magnetic particle and combinations thereof. 
   
   
       12 . The method according to  claim 1 , wherein said solid phase is a glass fibre material having a length of 0.7 μm to 2 μm. 
   
   
       13 . A method for the separation, purification and recovery of a long- and/or short-chain nucleic acid, comprising:
 adding a binding buffer to a reaction assay containing a nucleic acid, to obtain a mixture;   transferring said mixture to a solid phase, to bind said nucleic acid to said solid phase; and   eluting said nucleic acid from said solid phase;   wherein the binding buffer comprises at least one citric acid salt and at least one alcohol.   
   
   
       14 . The method according to  claim 13 , which does not comprise washing of the nucleic acids bound to the solid phase. 
   
   
       15 . The method according to  claim 13 , wherein the binding buffer does not comprise (i) a chaotropic salt, or (ii) a combination of a salt with a monovalent cation and a salt with a multivalent cation. 
   
   
       16 . The method according to  claim 13 , wherein the citric acid salt represents a salt with a singly positively charged cation. 
   
   
       17 . The method according to  claim 13 , wherein a hydrogen citrate or a dihydrogen citrate or a mixture thereof is introduced as citric acid salt. 
   
   
       18 . The method according to  claim 13 , wherein the citric acid salt is selected from the group consisting of di-ammonium hydrogen citrate, ammonium dihydrogen citrate, tri-sodium citrate, di-sodium hydrogen citrate, sodium hydrogen citrate, tri-potassium citrate, di-potassium hydrogen citrate, potassium hydrogen citrate and mixtures thereof. 
   
   
       19 . The method according to  claim 13 , wherein an alcohol concentration of the binding buffer is between 20%-90 wt. %. 
   
   
       20 . The method according to  claim 13 , wherein said alcohol is methanol, ethanol, propanol, isopropanol, ethylene glycol, polyethylene glycol, gycerin or mixtures thereof 
   
   
       21 . The method according to  claim 13 , wherein the ion strength of said binding buffer during said binding of said the nucleic acid to said solid phase is less than 100 mM. 
   
   
       22 . The method according to  claim 13 , wherein said solid phase is selected form the group consisting of a glass fibre material, a silica gel, a suspension of a mineral support, a functionalized magnetic particle and combinations thereof. 
   
   
       23 . The method according to  claim 13 , wherein said solid phase is a glass fibre material having a length of 0.7 μm to 2 μm. 
   
   
       24 . A test kit for carrying out the method according to  claims 1  or  13 , comprising:
 at least one alcohol;   at least one citric acid salt;   a solid phase; and   an elution buffer.   
   
   
       25 . A method for the purification of a PCR product, a restriction assay or a sequencing assay, comprising:
 contacting the test kit of  claim 24  with a PCR product, a restriction assay or a sequencing assay.