# Rapid, contamination-less, and efficient environmental DNA filtration system

## TL;DR

This paper introduces a new filtration system for collecting environmental DNA from deep-sea water, making the process faster, more efficient, and less prone to contamination.

## Contribution

The novel filtration systems allow rapid, contamination-free processing of multiple replicates from large volumes of deep-sea water.

## Key findings

- The new systems reduce filtration time and contamination by eliminating the need for water transfer.
- The systems enable simultaneous processing of 24 replicates using simple and cost-effective methods.

## Abstract

Due to the sporadic distribution and trace amount of environmental DNA (eDNA) in deep-sea water, in the context of biodiversity monitoring, large volumes of filtration and multiple filtration replicates are required for eDNA metabarcoding. To address issues tied to the use of multiple filtration devices and large filtration volumes (e.g., contamination, time consumption, etc.), we have developed two systems for simple, rapid, and contamination-less filtration simultaneously that allow for the processing of multiple sample replicates from large volumes of water. First, the water from a Niskin bottle was filtered directly using a solenoid pump. Second, the pumped deep-sea water, using the siphon effect, was directly filtered by a filtration device driven by water pressure. This system can process 24 replicates simultaneously without the need for expensive equipment and active driving force. Compared with conventional filtering methods, e.g., peristaltic pumps, the proposed systems reduce filtration time, minimizing contamination, and enabling the simultaneous acquisition of multiple replicates. Overall, the systems presented here provide an effective approach for eDNA metabarcoding analysis, particularly for the filtration of large volumes of water containing small amounts of eDNA, such as deep-sea water.

•The present systems reduce filtration time and contamination without water having to be transferred.•Simultaneous multiple replicates improve the efficiency and reliability of biodiversity assessments.

The present systems reduce filtration time and contamination without water having to be transferred.

Simultaneous multiple replicates improve the efficiency and reliability of biodiversity assessments.

Image, graphical abstract