A Novel Handheld High-Throughput Device for Rapid Detection of Phytoplankton in Ship's Ballast Water

Detection of live microalgae is critical to ballast water treatment. A novel handheld high-throughput ballast water rapid detection device based on microfluidic chip and fluorometry for counting single living microalgae cell is demonstrated in this article. The viability of individual microalgae cells can be evaluated and the number of the living microalgae cells in an aqueous solution sample can be obtained at a rate of one milliliter per minute in a fully automatic and real-time manner. It is experimentally confirmed that the detection results of this device are not influenced by free chlorophyll from the lysed microalgae, nor by the salinity and turbidity of the sample within the variation range of ballast water. Furthermore, this device has been used in a port to test the actual ballast water samples processed by ballast water treatment systems based on different principles or loaded at different locations, and the conclusion of this device on the qualification of the ship is consistent with the conclusion of the laboratory standard test. To the best of our knowledge, this is the first ballast water rapid detection device using a microfluidic chip as the detection platform, which can be used on board of ships for on-site counting the numbers of the living microalgae cells in ballast water.