Plasmid DNA (pDNA) is a circular, double-stranded DNA molecule that exists independently of the chromosomal DNA within bacterial cells and is capable of autonomous replication. In biopharmaceutical manufacturing, plasmid DNA serves as a critical starting material and raw material for the production of viral vectors — including AAV, adenoviral, and lentiviral vectors — as well as for mRNA synthesis, transient transfection, and DNA vaccine development.
