METHOD OF SEPARATING EXTRA-CHROMOSOMAL DNA FROM OTHER CELLULAR COMPONENTS

摘要

The invention relates to a method of separating extra-chromosomal DNA from RNA. It also relates to DNA produced by the method and pharmaceuticals derived from such DNA, for example, DNA vaccines. The method comprises separating extra-chromosomal DNA from RNA without first digesting the RNA, and comprises: i) lysing cells comprising extra-chromosomal DNA to form a lysate; ii) clarifying the lysate; and iii) subjecting the clarified lysate to tangential flow ultra filtration under conditions, which allow a substantial amount of the RNA to pass through a membrane whilst the extra-chromosomal DNA is retained. The preferred conditions include the use of a diafiltration buffer of low conductivity and diafiltration volumes of over 10 volume equivalents.