Ballast Water

03.06.2013  by  Bouke Krom

And why the CytoSense is very suitable


Image: WMN

With the CytoSense, plankton particles as large as these can be measured in the same run as 1-2 micrometer sized particles.

By now it is a well-known problem: cargo ships travelling all over the world bring water with them. Water that may contain exotic species. The CytoSense is especially suitable to detect these invaders!

The water is used as ballast for stability when the ship is not completely loaded with cargo. This ballast water is pumped out of the tanks in a very different location then where it is acquired. The ballast water may contain species harmful to the local ecosystem.
Currently numerous efforts are made to treat and analyze this water to assert that there are no living invasive species present when the water is pumped out. The CytoSense instrument is especially well suited to analyze the results of treatments, and to verify the amount of cells left.
With the CytoSense, direct measurements without sample preprocessing can be done. The instrument does not suffer from clogging, and can measure an extremely large particle size range - small and large particles can be detected in one go. Since it can be easily carried around, it is possible to bring the instrument to the sample, instead of bringing the sample to a lab. The CytoSense has a proven suitability for use on ships and in extreme environments (think about vibrations on a ship, unstable power sources, etc.).
Not only can the CytoSense accommodate to a large size range in particles, it can also handle very different concentrations. A high sediment or debris load poses no problems while it can also analyze very clean water (e.g. after treatment) with high accuracy. A sample flow rate range of 0.1 ul/ sec to 30 ul/sec makes sure that the data stream can be kept manageable. In any of such situations, concentration measurements are reliable and accurate.
The features of the CytoSense make for an all in one approach: both bacteria analysis (with staining options) and phytoplankton analysis, from picoplankton to large organisms (1 mm) can be done with one sample, in one procedure. For larger organisms there is a better classification than 'traditional' cytometers owing to the pulse shape data, and a length determination is direct and reliable.
In addition to the flowcytometric data, the CytoSense can also target specific groups of particles for picturing. One can accurately image most particles around the 50 um size or for instance, or apply a uniform imaging which will enhance the capture of rare particles and aliens - which is important for the detection of invasive species.
To gain more experience in these matters CytoBuoy participates in multiple projects relating to this field. Current developments include an automated staining device, automatic data classification and a more accurate quantification of the D2 measure.