What is the average amount of DNA and RNA present in 1 ml normal serum?
FAQ ID -635

According to an Interview with Professor Dennis Lo published in QIAGEN News Molecular Diagnostics, Issue No. 5, 2002, healthy individuals have about 500-1000 genome equivalents (DNA) per ml serum/plasma.

For free-circulating DNA in plasma, the concentration can range from 1–100 ng/ml in healthy individuals.