Process for the reduction of endotoxins in a plasmid preparation using a carbohydrate non-ionic detergent with silica chromatography

1. A method for reducing endotoxin levels in a nucleic acid solution comprising:

a) contacting a nucleic acid solution with a carbohydrate non-ionic detergent selected from the group consisting of alkyl thioglucosides, alkyl glucosides and alkyl maltosides;

b) contacting the solution resulting from step a) to an inorganic binding matrix;

c) washing the binding matrix resulting from step b) to obtain a nucleic acid composition having an endotoxin content of less than 100 EU/mg.

2. The method of claim 1 , further comprising eluting the nucleic acid composition from the inorganic binding matrix of step c).

3. The method of claim 2 , wherein the eluted nucleic acid composition comprises an average plasmid DNA yield of about 15 ug to about 50 ug and an average endotoxin level from about 20 EU/mg to about 100 EU/mg.

4. The method of claim 1 , wherein the carbohydrate non-ionic detergent is n-octyl-β-D-thioglucopyranoside.

5. The method of claim 1 , wherein the inorganic binding matrix is selected from the group consisting of silica, diatomaceous earth, aluminum oxides, glass, titanium oxides, zirconium oxides, and hydroxyapatite.

6. The method of claim 1 , wherein the inorganic binding matrix is silica.

7. The method of claim 1 , wherein the nucleic acid solution is a plasmid DNA solution.

8. The method of claim 1 , wherein the nucleic acid solution comprises double-stranded RNA or DNA, RNA/DNA hybrids, DNA fragments, oligonucleotides, amplified DNA or RNA, BACs, plasmid DNA, or a combination thereof.

9. The method of claim 1 , wherein the nucleic acid solution from step a) comprises a binding solution.

10. The method of claim 9 , wherein the binding solution comprises a chaotropic substance.

11. The method of claim 10 , wherein the chaotropic substance is a chaotropic salt selected from the group consisting of a guanidinium salt, urea, an alkali thiocyanate, an alkali halide, an alkali perchlorate, and a combination thereof.

12. The method of claim 11 , wherein the chaotropic salt is guanidine hydrochloride.

13. The method of claim 1 , wherein step c) comprises washing with a binding solution, an alcohol solution, a carbohydrate non-ionic detergent, or a combination thereof.

14. The method of claim 1 , further comprising obtaining the nucleic acid solution to be used in step a) from a biological source by a digestion method.

15. The method of claim 14 , wherein the digestion method comprises alkaline lysis, centrifugation, filtration or precipitation.

16. The method of claim 1 , wherein the nucleic acids solution is a cleared lysate.