Compositions, methods, and kits for isolating nucleic acids
Disclosed here is a composition for isolating nucleic acids from a biological sample, comprising a chaotropic compound and a solvent, wherein the solvent comprises a nitrile compound, tetrahydrofuran, or a combination thereof. Also disclosed is a method for binding nucleic acids to a matrix, comprising: contacting the nucleic acids from a biological sample with the matrix in the presence of a chaotropic compound and a solvent, wherein the solvent comprises a nitrile compound, tetrahydrofuran, or a combination thereof, thereby binding the nucleic acids to the matrix. Further disclosed is a kit for isolating nucleic acids from a biological sample comprising a binding buffer, wherein the binding buffer comprises a chaotropic compound and a solvent, wherein the solvent comprises a nitrile compound, tetrahydrofuran, or a combination thereof.
1. A composition comprising:
a binding buffer comprising 4 M to 6 M of guanidine chloride, 10% to 20% of acetonitrile and less than 2% alcohol;
a matrix comprising siliceous materials, silica gel, glass, glass fiber, zeolite, kaolin, gelatinous silica, or a combination thereof; and
cell-free fetal DNA or circulating tumor DNA,
wherein at least 50% of the cell-free fetal DNA or circulating tumor DNA having a size of 72 bp is bound to the matrix.
2. The composition of claim 1 , wherein the binding buffer comprises 13% to 18% of acetonitrile.
3. The composition of claim 1 , wherein the pH of the binding buffer is 4 to 8.
4. The composition of claim 1 , wherein the composition comprises 4 M to 5 M of guanidine chloride.
5. The composition of claim 1 , wherein the binding buffer further comprises a chelating compound comprising ethylenediaminetetraccetic, ethyleneglycol-bis(2-aminoethylether)-N,N,N′,N′-tetraacetic acid, citric acid, N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine, 2,2′-Bipyridyl, deferoxamine methanesulfonate salt, 2,3-Dihydroxybutanedioic acid, or a combination thereof.
6. The composition of claim 1 , wherein the binding buffer further comprises a detergent comprising polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether, polyoxyethylene 20 sorbitan monolaurate, N-lauroyl sarcosine, sodium dodecylsulfate, dodecyldimethylphosphine oxide, sorbitan monopalmitate, decylhexaglycol, 4-nonylphenyl-polyethylene glycol, or a combination thereof.
7. The composition of claim 6 , wherein the binding buffer further comprises 3% to 6% of polyethylene glycol p-(1,1,3,3-tetramethylbutyl)-phenyl ether.
8. The composition of claim 1 , wherein the composition comprises the circulating tumor DNA.
9. The composition of claim 1 , wherein the composition comprises the cell-free fetal DNA and further comprises cell-free maternal DNA.
10. The composition of claim 1 , wherein the binding buffer is free of isopropanol.
11. The composition of claim 1 , wherein at least 70% of the cell-free fetal DNA or circulating tumor DNA having a size of 72 bp is bound to the matrix.
12. The composition of claim 1 , wherein the matrix comprises glass fiber.
13. A method for binding nucleic acids to a matrix comprising:
contacting cell-free fetal DNA or circulating tumor DNA from a biological sample with a matrix comprising siliceous materials, silica gel, glass, glass fiber, zeolite, kaolin, gelatinous silica, or a combination thereof, in the presence of a binding buffer comprising 4 M to 6 M of guanidine chloride, 10% to 20% of acetonitrile and less than 2% alcohol,
thereby binding 50% of the cell-free fetal DNA or circulating tumor DNA having a size of 72 bp to the matrix.
14. The method of claim 13 , further comprising:
incubating a biological sample comprising cell-free fetal DNA or circulating tumor DNA with a protease prior to contacting the nucleic acids with the matrix;
washing the matrix with a washing buffer after contacting the cell-free fetal DNA or circulating tumor DNA with the matrix;
drying the matrix; and/or
eluting the nucleic acids from the matrix with an elution buffer.
15. A kit for isolating nucleic acids from a biological sample, comprising:
a binding buffer comprising 5 M to 8 M of guanidine chloride, 15% to 35% of acetonitrile, less than 2% alcohol and is free of both a nucleic acid sample and isopropanol; and
a matrix for binding nucleic acids comprising siliceous materials, silica gel, glass, glass fiber, zeolite, kaolin, gelatinous silica, or a combination thereof.
16. The kit of claim 15 , wherein the kit further comprises:
a digestion buffer comprising a protease;
a washing buffer; and/or
an elution buffer.
17. The kit of claim 15 , wherein the matrix comprises glass fiber.