A tailored MoS2 membrane with strong DNA-binding capability enhances aquatic biota detection through environmental DNA metabarcoding

ABSTRACT Active environmental DNA (eDNA) sampling, typically involving water filtration, offers the advantage of capturing relatively high concentrations of eDNA, making it particularly valuable in aquatic environments with low DNA concentrations. However, this approach faces several limitations, including low DNA-capture efficiency, limited molecular selectivity and the risk of contamination during filtration and handling. Moreover, commonly used membrane materials often lack strong and specific DNA-binding affinity, which reduces detection sensitivity and compromises biodiversity assessment. To address these challenges, we developed a MoS2-coated mixed cellulose ester membrane that significantly enhances both the efficiency and the selectivity in capturing eDNA. The MoS2 coating facilitates preferential interactions with DNA via van der Waals forces between the sulfur atoms in MoS2 and the oxygen or nitrogen atoms in DNA bases. Laboratory and field tests with marine fish confirmed that the MoS2-coated membrane significantly enhanced the selectivity and sensitivity of eDNA-based biota detection. This work represents the first application of a 2D nanomaterial-based membrane for eDNA collection and detection. Furthermore, the membrane is low-cost and scalable, and requires no further processing. This invention offers a promising strategy for the development of 2D nanomaterials-based eDNA-sampling tools and showcases their broader potential in environmental biotechnology applications.