Hidden Secrets Behind Dots: Improved Phytoplankton Taxonomic Resolution Using High-Throughput Imaging Flow Cytometry.

Area of Science:

• Environmental Science
• Marine Biology
• Analytical Chemistry

Background:

• Phytoplankton are crucial primary producers and indicators of aquatic ecosystem health.
• Current monitoring methods like manual microscopy are labor-intensive and limit sampling frequency.
• Standard flow cytometry (FCM) lacks the taxonomic resolution for precise phytoplankton identification.

Purpose of the Study:

• To evaluate the taxonomic resolution of imaging flow cytometry (IFC) for phytoplankton analysis.
• To compare IFC capabilities with standard FCM for phytoplankton species discrimination.
• To demonstrate IFC's potential for robust, high-throughput phytoplankton monitoring.

Main Methods:

• Utilized an ImageStream X Mk II imaging flow cytometer for phytoplankton analysis.
• Compared numerical evaluations of IFC data with standard FCM (FACSAria II).
• Analyzed laboratory-grown phytoplankton cultures at various taxonomic differentiation levels.

Main Results:

• IFC demonstrated taxonomic resolution comparable to standard FCM.
• Image data from IFC enabled detailed characterization and discrimination of phytoplankton species, strains, and subpopulations.
• Developed image-based cytograms for enhanced visualization of individual cells.

Conclusions:

• IFC provides a powerful tool for high-throughput phytoplankton monitoring with high taxonomic resolution.
• IFC overcomes limitations of standard FCM, offering detailed cellular information and archivable data.
• This technology can enhance machine-learning classifications and improve our understanding of aquatic ecosystems.