Quantifying the Extent of Calcification of a Coccolithophore Using a Coulter Counter

Area of Science:

• Marine Biology
• Biogeochemistry
• Analytical Chemistry

Background:

• Coulter Counters typically require calibration with latex beads for accurate particle sizing.
• Biogenic calcite in coccolithophores presents calibration challenges for standard Coulter Counter methods.
• Quantifying cellular calcite content in coccolithophores has been previously unachievable with Coulter Counters.

Purpose of the Study:

• To develop and validate a novel calibration methodology for Coulter Counters to accurately quantify calcite content in coccolithophores.
• To determine the extent to which Coulter Counters can provide precise measurements of calcite in single-species coccolithophore populations.

Main Methods:

• Developed a new calibration technique based on tracking the acid-driven dissolution of calcite.
• Applied dynamic tracking of the calcite dissolution reaction to determine cellular calcite content.
• Utilized Coulter Counter measurements in conjunction with the new calibration method.

Main Results:

• Successfully established a calibration method for Coulter Counters to measure cellular calcite content.
• Enabled absolute quantification of calcite per coccolithophore cell for the first time.
• Demonstrated the accuracy of the Coulter Counter for analyzing biogenic calcite in coccolithophores.

Conclusions:

• The novel calibration methodology overcomes previous limitations in quantifying biogenic calcite.
• Coulter Counters, when calibrated with this new method, can provide accurate absolute measurements of calcite content per cell.
• This advancement opens new avenues for research into coccolithophore calcification and its environmental implications.