Capture and Protection of Environmental DNA in a Metal-Organic Framework

Area of Science:

• Environmental science
• Molecular biology
• Materials science

Background:

• Environmental DNA (eDNA) enables non-invasive species detection but faces challenges with low abundance and degradation.
• Current active filtration methods for eDNA collection are often time-consuming and impractical for fieldwork.
• Degradation agents like enzymes, UV radiation, and microorganisms compromise eDNA sample integrity.

Purpose of the Study:

• To develop and evaluate a filter-free, one-pot procedure for capturing environmental DNA (eDNA) using a metal-organic framework (MOF).
• To assess the efficiency and stability of eDNA captured by zeolitic imidazolate framework 8 (ZIF-8) in various aquatic samples.
• To demonstrate ZIF-8's capability in preserving eDNA integrity against degradation and over time.

Main Methods:

• A filter-free, one-pot method was developed utilizing zeolitic imidazolate framework 8 (ZIF-8) for eDNA capture.
• The method was tested on 15 mL water samples from diverse aquatic environments (aquarium, river, sea).
• Salmon DNA was spiked into samples to represent eDNA, and capture efficiency was assessed using species-specific quantitative polymerase chain reaction (qPCR).

Main Results:

• ZIF-8 demonstrated high capture efficiency (>98%) for spiked salmon DNA across all tested aquatic sample types.
• Captured DNA exhibited resistance to degradation from endonucleases and UV light.
• Genomic DNA remained stable for up to 28 days at 37 °C in ZIF-8 captured samples, significantly longer than untreated controls (below detection limit by day 6).

Conclusions:

• Zeolitic imidazolate framework 8 (ZIF-8) provides an effective solution for capturing environmental DNA (eDNA) from aquatic environments.
• The ZIF-8 method overcomes critical challenges related to eDNA instability and degradation, enhancing sample preservation.
• This filter-free approach offers a promising advancement for non-invasive biodiversity assessments and species detection using eDNA.