Traditional marine ecotoxicity testing is inherently labor intensive, requiring extensive manual procedures both to set up the tests and more importantly to collect experimental readouts. Moreover, static test procedures offer poor control of water parameters such as toxicant concentration and dissolved oxygen, which are important considerations in evaluating environmental impacts of aquatic pollution. So far only minimal levels of automation have been adopted in ecotoxicology. Our current work attempts to address the current limitations by capitalizing on latest advances in microfluidics, 3D printing and laser micromachining technologies to develop highly customized, low cost and high-throughput devices.
Here we for the first time introduce a proof-of-concept laboratory automation system to perform ecotoxicity tests on the marine amphipod Allorchestes compressa in a microfluidic environment. Our innovative system incorporated a microperfusion Lab-on-a-Chip device that enabled the biotests to be run in both closed- or open-loop regimens. Miniaturized video cameras were utilized to monitor the amphipods movement patterns during the experiments. Furthermore innovative video analysis algorithms was applied for detection of sub-lethal endpoints such as changes in swimming activity that would otherwise go unnoticed. A key advantage of this flow-through system as compared to conventional approach is the automation of analysis and emphasis on sub-lethal behavioral parameters.
We present preliminary data validating the technology and compared to a gold standard method for testing organisms from the order Amphipoda This work provides a foundation to enable automation of ecotoxicity biotests performed on marine test organisms.