Researchers invent novel eDNA membrane to advance understanding of inshore fish diversity

Researchers at City University of Hong Kong have developed a specialized membrane that significantly enhances the detection of environmental DNA (eDNA) from marine organisms. This innovation could improve our understanding of inshore fish diversity and overall marine ecosystem health. eDNA refers to trace genetic material released into water by organisms like skin cells, mucus, and excreta.

Monitoring eDNA allows scientists to determine which species are present in a body of water without physically capturing the organisms. Traditional membranes struggle to capture the extremely low concentrations of DNA found in seawater, limiting the effectiveness of eDNA analysis. In collaboration with other universities, CityUHK researchers led by Professor Kenneth Leung Mei-yee developed a membrane coated with an ultrathin layer of the 2D material molybdenum disulfide (MoS₂).

This modification significantly boosts the membrane's ability to capture DNA in water, making it a more sensitive and reliable tool for monitoring marine biodiversity. The team demonstrated the membrane's effectiveness in both laboratory and field tests. In controlled experiments, it accurately identified a variety of tropical coral reef fish.

Field testing at Hoi Ha Wan Marine Park showed the membrane detected more fish species, including anchovies and carangid fish, without altering the overall fish community assessment. The membrane is simple to produce and cost-effective, and can be integrated into existing water sampling processes. Researchers believe it has significant potential for marine conservation, ecological surveys, and long-term environmental monitoring, particularly in areas with rich biological resources but challenging survey conditions.