We are CytoBuoy b.v., a Dutch company with over 25 years of experience in manufacturing particle analysis instruments and software for researchers in aquatic science and other disciplines. We are proud that we can put our experience, vision and skills to work on making tools that help scientists pursue important goals such as understanding ecological processes in the environment. The personal contacts with our customers are a source of joy and invaluable for the continuous innovation of our products and services.



Design of a flow cytometer for phytoplankton (the Optical Plankton Analyser) at the Radiobiological Institute of the Netherlands Organization for Applied Scientific Research (TNO) and funded by The Netherlands Foundation for Technical Sciences (STW). The instruments were validated by the Dept. of Aquatic Ecology, University of Amsterdam and the National Institute for Coastal and Marine Management, Rijkswaterstaat (RIKZ).

  • introduction of extremely large flow cell (1 mm) for a wide range of particles 
  • first (hard wired) digital pulse processing for an extreme dynamic range


This technology was further explored in the 1992 MAST II project EurOPA, funded by the Marine Science and Technology program of the European Commission. The partners in this project pioneered many aspects such as:

  • video imaging-in-flow (Max-Planck Institute für Biochemie) 
  • digital pulse shapes (RIKZ) 
  • azimuthally resolved forward light scatter (Dept. of Physics and Applied Physics, University of Strathclyde) 
  • fluid switch sorter with direct sorting on filters (Dubelaar Res. Instr. eng.) 
  • neural network analysis (School of biology, Univ. of Wales, College of Cardiff) 
  • multivariate statistical methods (Plymouth Marine Laboratory) 

1996 - 2000

The CytoBuoy project was also funded by the MAST III Marine Science and Technology program of the European Commission. We pioneered the downsizing of the core (Eur)OPA technology for autonomous and in situ operation. Partners: Datawell b.v., Oceanor s.a., Dubelaar Res. Instr. eng., Pyxilla, Kantakun. 

  • introduction of storing of fully digitized pulse shapes 
  • invention of recirculating sheath fluid 
  • introduction of two stage injector for moving platforms 
  • introduction of holographic grating for fluorescence color separation 
  • invention of non-gaussian laser intensity profile for high sample flow rates 
  • first radio operated flow cytometer in floating buoy


Founding of CytoBuoy b.v. 

  • first CytoSense benchtop instruments delivered 
  • first submersible flow cytometer (down to 200 meter) 
  • introduction of CytoClus: cluster analysis with fourier analysis of pulse shapes


  • invention of the curvature parameter 
  • introduction of submersible battery pack for CytoSub 
  • CytoSub control and data download through bluetooth


  • modular redesign and downsizing of the CytoSense to 1 cubic foot 
  • introduction of picoplankton modules 
  • CytoBuoy in Oceanor SeaWatch mini hull with solar panels


  • full USB control of CytoSense and realtime download of particle scans
  • CytoSub control and data download through WiFi antenna
  • Highly improved injector design


  • USB comunication through 280 meter of marine cable 
  • automatic sample speed adjustment to particle concentration 
  • water depth triggered sampling by CytoSub


  • automated sample pressurizing CytoSense (for collapsing of intracellular gas vesicles)
  • introduction of a second excitation laser using superposed focus and electronic signal separation


  • miniature imaging-in-flow (IIF) camera system photographing particles at full core velocity
  • realtime particle preselection module evaluating individual silico-images prior to photographic capturing


  • one-on-one matching function in the output data files between IIF photos and silico-images 
  • new low power high system pressure pump for sample loop filling (cytosub, low dead volume and self-debubbling)
  • improved pump drive for sample pump (pulseless tube, with feedback and calibration wizard)
  • automated data clustering application "Easyclus" by Thomas Rutten Projects


  • internal sensor package for CytoSense performance monitoring and stabilizing
  • CytoSense communication speed upgrade to USB 2
  • multipoint sampling accessory for the CytoSense
  • particle D-2 diameter determination from captured photos (IMO Ballast Water Convention)
  • Pre-targeted ('smart') trigger function in the CytoUSB data acquisition software 


Currently in development:

  • new CytoSense hull design to meet EX specifications (spark proof and fully enclosed)
  • an horizontal-vortex, really charming sample stirring device
  • new CPLD based digital data grabber design with real time smart triggering capability
  • IIF "in focus" photo preselection by coupling to the curvature data
The cytobuoy crew
Lowering a sub in Marseille
CytoSub deployed on board of an unmanned submarineCytoSub deployed on board of an unmanned submarineFirst test of current buoy design in Reeuwijk (2005)
CytoSub deployed on board of an unmanned submarine
CytoSub deployed on board of an unmanned submarine
First test of current buoy design in Reeuwijk (2005)
The improved design for the CytoSub circulation pump
The very compact image-in-flow camera