ISO 21571:2005 provides general requirements and specific methods for DNA extraction/purification and quantification. These methods are described in Annexes A and B.

ISO 21571:2005 has been established for food matrices, but could also be applicable to other matrices, such as grains and feed.

It has been designed as an integral part of nucleic-acid-based analytical methods, in particular ISO 21569 on qualitative analytical methods, and ISO 21570 on quantitative analytical methods.