You can tell a lot about what's going on in undersea environments simply by seeing which compounds are being released into the water by marine organisms. An experimental new device could soon make that process quicker and easier than ever before.
Ordinarily, if scientists are looking for chemicals such as eDNA (environmental DNA) in places like coral reefs, they have to collect water samples which are subsequently analyzed in a lab.
The problem is, some compounds may only be present in very low concentrations, so they might be missed by standard sampling. Collecting and analyzing a greater amount of water may address that issue, but doing so involves a lot more work for both lab technicians and field scientists – particularly if the samples are being obtained at depth, by scuba divers.
With that conundrum in mind, Thierry Pérez, Charlotte Simmler and colleagues at France's Aix-Marseille University developed a tool known as the I-SMEL (In Situ Marine moleculE Logger).
The waterproof (but not too buoyant) device is carried by a diver to the desired underwater location, and activated via a push of a button. An integrated pump then pushes seawater through a series of make-up-remover-pad-like solid phase extraction disks, which collect and concentrate waterborne molecules for subsequent analysis.
In a test of the technology, the I-SMEL was successfully used to collect compounds released by large sponges in Mediterranean Sea caves at a depth of 65 feet (20 m). When the concentrated compounds were subsequently analyzed via mass spectrometry, some of them were found to have molecular structures that were previously unknown to science. The university states that such unique compounds may someday find use in new consumer products.
The scientists are now working on an "unmanned" version of the device that could be anchored deep underwater for long periods of time, autonomously filtering seawater for later analysis.
A paper on the research was recently published in the journal ACS Central Science.
Source: American Chemical Society