Antifreeze solution improves DNA recovery by preserving the integrity of pathogen-infected blood and other tissues.

Preserving blood samples for shipping and later DNA extraction has been performed by cooling, freezing, drying, freeze-drying, and protease treatment, among other methods. Most methods to preserve field samples for further DNA extraction do not prevent cellular and DNA damage or are useful only in preserving them for short periods. This report introduces a novel method for blood and tissue that allows preservation in freezing temperatures for a prolonged period of time. The solution reported here (20% ethylene glycol-propylene glycol) preserves cells and tissues integrity, as judged by microscopic analysis, and improves DNA yield and quality.