Abstract: Provided herein is a method to reduce the endotoxin contamination in plasmid preparations. In the described method, plasmid DNA and endotoxins are bound to an anionic exchange matrix and are brought into contact with a wash buffer, comprising a combination of branched secondary alcohol ethoxylates with varying ethylene oxide chain lengths, wherein the branched secondary alcohol ethoxylates with the shorter ethoxylate chain is present in the washing buffer in excess compared to the branched secondary alcohol ethoxylate with the longer ethoxylate chain. The resulting purified plasmid has minimal endotoxin contamination levels and is considered endotoxin-free. Furthermore, provided are wash buffers comprising a combination of branched secondary alcohol ethoxylates with varying ethylene oxide chain lengths, kits comprising such wash buffers and the use of such wash buffers for reducing the endotoxin contamination in plasmid preparations.

Abstract: The invention relates to a device for extracting nucleic acid from a formalin-fixed and paraffin-embedded sample comprising a hollow body having an inlet port and an outlet port and a filter layer arranged within the hollow body, wherein the device is characterized in that the filter layer has an oil repellency of at least grade 5 according to the test method by AATCC-118 (1997). The invention further relates to a method for extracting nucleic acids from a formalin-fixed and paraffin-embedded sample, and a kit comprising the inventive device.

Abstract: Disclosed is a process for purifying nucleic acids, especially plasmid DNA, from a nucleic acid-containing, biologic sample, consisting of (a) preparation of a fluid sample containing nucleic acid and endotoxin each in dissolved form; (b) precipitation at least of nucleic acid and endotoxin from the fluid sample; (c) washing of the components of the fluid sample precipitated out in step b) in order to at least partially remove the endotoxin with at least one washing solution, which contains at least one amine compound with at least two carbon atoms and with a molar mass of ?500 g/mol and; at least one organic solvent different from the aforementioned amine compound and has a pH-value (20° C.) in the range from pH 3.0 to pH 8.5, and; (d) dissolution of the remaining nucleic acid from the washed, precipitated constituents from step c) using a dissolving buffer and collection of the dissolved nucleic acids in a separate receptacle. The process is suitable for the effective and economical removal of endotoxins.

Abstract: A process for purifying nucleic acids, especially plasmid DNA, from a nucleic acid-containing, biologic sample, consisting of the following steps: a) Preparation of a fluid sample containing nucleic acid and endotoxin each in dissolved form; b) Precipitation at least of nucleic acid and endotoxin from the fluid sample; c) Washing of the components of the fluid sample precipitated out in step b) in order to at least partially remove the endotoxin with at least one washing solution, which contains (i) at least one amine compound with at least two carbon atoms and with a molar mass of ?500 g/mol and; (ii) at least one organic solvent different from the aforementioned amine compound and has a pH-value (20° C.) in the range from pH 3.0 to pH 8.5, and; d) Dissolution of the remaining nucleic acid from the washed, precipitated constituents from step c) using a dissolving buffer and collection of the dissolved nucleic acids in a separate receptacle.