Abstract: A diaphragm pump has at least one pump chamber, the pump chamber being connected to an inlet chamber via an inlet valve and to an outlet chamber via an outlet valve. The inlet valve has an inlet opening which can be closed by an inlet valve body, and the outlet valve has an outlet opening which can be closed by an outlet valve body. The outlet opening surrounds the inlet opening, or the inlet opening surrounds the outlet opening.

Abstract: A diaphragm pump has at least one pump chamber, the pump chamber being connected to an inlet chamber via an inlet valve and to an outlet chamber via an outlet valve. The inlet valve has an inlet opening which can be closed by an inlet valve body, and the outlet valve has an outlet opening which can be closed by an outlet valve body. The outlet opening surrounds the inlet opening, or the inlet opening surrounds the outlet opening.

Abstract: The invention relates to a process for isolation of plasmid DNA from biomass by means of an aqueous 2-phase system having a polymer component and a salt component, characterized in that the resuspension of the biomass employed, the alkaline lysis of the biomass, the neutralization of the alkaline lysis batch and the separation of the plasmid DNA from the contaminants are carried out in a single reaction vessel (one-pot process) rendered possible in that the neutralization of the alkaline lysis batch is carried out in one and the same container by addition of potassium phosphate and one component of the aqueous 2-phase system is therefore already present. The second component of the aqueous 2-phase system is a PEG having a molecular weight of the mathematical average of about 600 g/mol to 1,000 g/mol.

Abstract: The invention relates to a process for selective, reversible adsorption of nucleic acids to a support material, which process is characterized in that (a) a nucleic acid-containing mixture having a cosmotropic salt content of at least 1 mole is contacted with said support material, whereupon the nucleic acid(s) is (are) adsorbed from said nucleic acid-containing mixture to said support material, and (b) the nucleic acid(s) bound to the support material is (are) detached from the support material by means of an aqueous solution having a salt content of no more than 1 mole.

Abstract: The invention relates to a method for stripping undesired nucleic acid components from double-stranded DNA, in particular, super-coiled plasmid DNA. The method according to the invention is characterised by the steps: (a) provision of a mixture containing completely and/or partly double-stranded nucleic acids and optionally single-stranded nucleic acids; (b) resuspension of the mixture from step (a) in an aqueous, low-molarity buffer system with low ionic strength and low buffer effect; (c) adjusting conditions in the mixture from step (b), under which the completely and/or partly double-stranded nucleic acids are denatured; (d) further addition of buffer and a polymer component to the mixture from step (c); (e) incubation of the mixture from step (d) for a time which is sufficient for the formation of an aqueous two-phase system with an upper and lower phase; and (f) removal of the upper phase containing the single-strand nucleic acid and collection of the double-strand nucleic acid from the lower phase.

Abstract: The invention relates to a process for isolation of plasmid DNA from biomass by means of an aqueous 2-phase system having a polymer component and a salt component, characterized in that the resuspension of the biomass employed, the alkaline lysis of the biomass, the neutralization of the alkaline lysis batch and the separation of the plasmid DNA from the contaminants (such as e.g. cell debris, RNA and gDNA) are carried out in a single reaction vessel (one-pot process). According to the invention, this is rendered possible in that the neutralization of the alkaline lysis batch is carried out in one and the same container by addition of potassium phosphate and one component of the aqueous 2-phase system is therefore already present, and in that the second component of the aqueous 2-phase system is a PEG having a molecular weight of the mathematical average of about 600 g/mol to 1,000 g/mol, but is preferably formed from a mixture of PEG 600 and PEG 1000.