eDNA Sample Collection, Filtration and Preservation
The ideal location and timing of eDNA sampling, along with the number of samples to collect will depend on the target species and specific objectives of the study.
A properly designed survey is required to generate meaningful eDNA results. Expert consultation is advised.
Water samples should be filtered and preserved with either silica desiccant beads or molecular grade ethanol (95 -100 % pure) within 24 hours of collection (and prior to submission to the lab). Note that ethanol is subject to transportation of dangerous goods regulations and may require a license to purchase. Maxxam recommends the use of silica desiccant beads.
Once preserved, the eDNA should be viable for 6 months, longer if it is stored in a non-self-defrosting freezer at -20ºC or colder. Lab extracted eDNA (in a buffered solution) will remain viable for years.
Resources for further information on eDNA sampling, filtration and preservation: