Environmental DNA monitoring has become one of the most effective tools available for non-invasive marine and freshwater ecological assessment. Rather than trawling, netting, or direct observation, marine eDNA sampling captures the genetic traces organisms leave behind in the water column – a more efficient, less disruptive approach to understanding what lives in an environment. If you’re new to the subject, our guide to what eDNA monitoring is and why it’s useful for marine biodiversity research covers the foundations.
Subsea Commercial Services now supplies both DOT eDNA sampler systems: the original autonomous eDNA Sampler and the newly available eDNA Rapid Sampler. Each is built around the same core purpose but optimised for different operational contexts. Understanding the difference is the first step to choosing the right tool for your project.
The DOT eDNA Sampler: built for long-term autonomous deployment
The DOT eDNA Sampler is designed for long-term environmental DNA monitoring in locations that are difficult or impractical to service regularly. It handles sample collection, cleaning, and preservation entirely onboard – a self-priming, self-cleaning, self-preserving system that operates independently once deployed.
Each filter cassette holds 9 DNA filters, and the sampler carries enough reagent chemistry to clean and preserve 3 full cassettes, for a total capacity of 27 DNA filters per deployment. Reagents are stored and deployed onboard, with no external support required.
Triggering is flexible: samples can be scheduled by date and time, activated by depth or pressure, or initiated by a third-party sensor or device via RS-232 serial connection. The self-cleaning cycle between each sample significantly reduces cross-contamination risk – an important consideration when data integrity is paramount.
This sampler is the right choice when access is the primary constraint. For a deeper look at how autonomous eDNA systems perform in practice – including deployment planning, contamination control, and power considerations – see our post on using autonomous eDNA sampling in marine environments.
The DOT eDNA Rapid Sampler: built for high-volume collection
The eDNA Rapid Sampler is the newest addition to the DOT range, and it takes a different approach to marine eDNA sampling. Rather than prioritising long-term autonomy, it’s optimised for high-volume collection in a compact, vehicle-compatible package.
Flow rates of up to 600 mL per minute mean it can collect up to ten times the sample volume per filter compared to the original sampler, in a fraction of the time. Nine dedicated pumps serve nine individual DNA filters, and the power management design to stagger in-rush current supports parallel collection: single, dual, or triplicate samples can be collected simultaneously from the same location.
Removing the onboard reagent system results in a significantly more compact footprint, making the Rapid Sampler well-suited to ROV or AUV payload bays where size and weight are always considerations. Communication options have also been expanded, with RS-232, RS-485, and Ethernet all supported for integration with wider vehicle or monitoring systems.
Environmental DNA monitoring applications
Both samplers support the same range of environmental DNA monitoring applications across marine and offshore environments.
Commissioning and decommissioning surveys for oil and gas infrastructure, offshore wind farms, and aquaculture sites require robust baseline and impact data. Both eDNA samplers are well-suited to generating that data non-invasively and at scale.
Targeted species detection is another core use case – whether monitoring for harmful algal species such as Alexandrium, tracking parasites or pathogens in aquaculture environments, or assessing biodiversity through indicator species.
In all cases, filters are returned for laboratory processing, where DNA extraction can be followed by methods such as qPCR for precise quantification and species identification.
Which eDNA sampler is right for your project?
The decision comes down to deployment context. If the priority is long-term, low-maintenance autonomous monitoring from a fixed or moored position, the autonomous eDNA Sampler’s built-in preservation and cleaning functions are a significant operational advantage. If the priority is collecting large sample volumes quickly – particularly from a mobile platform such as an ROV or AUV – the Rapid Sampler’s throughput and compact design make it the more practical choice.
In some project designs, both have a role: the Rapid Sampler is deployed during active survey passes, with the eDNA Sampler providing continuous background monitoring between visits.
Purchase or rent DOT eDNA samplers through SCS
SCS supplies both DOT eDNA sampler systems for purchase and rental. Whether you need long-term autonomous environmental DNA monitoring capability or high-volume rapid sampling for a specific survey campaign, we can help you identify the right solution and support you through deployment.
Get in touch with the SCS team to discuss your requirements.
