Collaborators at Eawag, the University of Basel, ETH Zurich and University of Zurich have come together to develop a faster, portable way to take sediment samples, extract porewater and analyse it in under 15 minutes.
Led by Beat Muller, the researchers combine a portable capillary electrophoresis instrument with MicroRhizon samplers in this Environmental Science :Processes & Impacts paper.
MicroRhizon samplers are made of chemically inert microporous tubing connected to a syringe and are inexpensive, portable and simple to use. The difficulty in analysis is that only a small sample volume is collected, extra handling and sample preparation is required and there is a risk of contamination in transferring the sample for analysis.
The previously developed portable capillary electrophoresis device with contactless conductivity detection eliminates these concerns as it enables sensitive detection of ionic compounds in the field immediately after sampling.
In this article, the team applies this combination to porewater sampling and analysis, giving high spatial resolution.
The method is validated by sampling of sediment from a eutrophic lake, comparing the results to those from ion chromatography. They successfully separate out major inorganic ionic compounds in under 15 minutes. The disturbance of the sediment samples is minimal and zero-oxygen conditions were maintained without difficulty. No splitting, acidification or dilution of the sample is necessary.
Such speedy porewater analysis will be beneficial for the study of oxidizing agents and nutrients in organic matter. Read the full article here as it’s now free to access for the next 4 weeks*
Sediment porewater extraction and analysis combining filter tube samplers and capillary electrophoresis
Natascha T. Torres, Peter C. Hauser, Gerhard Furrer, Helmut Brandl and Beat Müller
DOI: 10.1039/C3EM00068K
*Free access to individuals is provided through an RSC Publishing personal account. Registration is quick, free and simple
