New comparative study of Sterivex® filters and Smith-Root Inc. systems
A new conference paper has been released led by our Program Officer and wildlife ecologist, Dr Farley Connelly that puts Smith-Root Inc. sampling equipment to the test. Two experiments were conducted that compare the efficacy of traditional Sterivex® filters with automated sampling systems (including the Smith-Root Backpack Sampler and self-preserving filters).
The data was compiled from two EnviroDNA projects using different eDNA analysis methods of targeted species detection and multispecies (metabarcoding) analysis for assessing biodiversity.
Sampling Method
Experiment A: Comparing Sterivex® and Smith-Root - volume, turbidity and metabarcoding.
At each site, five Sterivex® samples were collected at different sampling locations around a waterbody filtering as much water as possible through each filter. 1.2 L of water was also collected from the same five sampling locations and pooled into a sterile bucket to form one 6 L pooled water sample. The Smith-Root sampler was then used to pump up to 6 L of water through a single 5.0 µm self-preserving filter from each bucket, resulting in one Smith-Root filter sample per site.
Experiment B: Comparing Sterivex and Smith-Root (2 pore sizes) – volume and target species (Amphibian sp.)
At each site, four water samples were processed through Sterivex® filters, two through a 1.2 μm Smith-Root filter and one through a 5.0 μm Smith-Root filter. As much water as possible was filtered through each filter.
Sterivex® filter (left), Smith-Root Backpack Sampler (middle), Smith-Root Self-Preserving filter (right)
Key Findings
- Smith-Root processed higher volumes of water. The volume of water processed by each filter differed significantly between filter types. A single Smith-Root 5.0 µm filter processed over four times more water on average than a single Sterivex 0.22 µm filter.
- Smith-Root performed better at single species detection in comparison to Sterivex®. This was true for both the 1.2 μm and 5.0 μm Smith-Root filters.
- Smith-Root self-preserving filters were more cost-effective. A single Smith-Root filter performed similarly to five Sterivex filters for metabarcoding on amphibians, highlighting the cost effectiveness of the Smith-Root filters.
Want to learn more?
Overall, this study provides evidence that the automated Smith-Root sampler is a more efficient sampling method compared to the manual Sterivex® technique. When comparing against five Sterivex® filters sampled at a site in our amphibian metabarcoding assay, mean species detected across sites was higher, although not significantly different.
It is also important to remember that there is no ‘one size fits all’ approach to eDNA sampling, and several factors are to be considered regarding methodology. If you want to find out the most suitable approach for your next project, get in touch, our team can provide expert advice based on your needs.
Acknowledgements
This research was funded in part by Melbourne Water