Used in biopharmaceutical quality control to detect residual E. coli DNA contaminants in recombinant protein or vaccine products produced using E. coli expression systems. Ensures product safety by verifying that host cell DNA levels are within regulatory limits set by the Chinese Pharmacopoeia (ChP). Commonly applied in downstream process validation during manufacturing of therapeutic proteins, where even trace amounts of genetic material must be quantified and minimized to prevent potential immunogenic or oncogenic risks. The kit enables sensitive, specific, and quantitative measurement of residual DNA, supporting compliance with strict regulatory requirements for biologicals.