Liquid-Phase Measurements of Photosynthetic Oxygen Evolution.

This chapter compares two different techniques for monitoring photosynthetic O ₂ production: the widespread Clark-type O ₂ electrode and the more sophisticated membrane inlet mass spectrometry (MIMS) technique. We describe how a simple membrane inlet for MIMS can be made out of a commercial Clark-type cell, and outline the advantages and drawbacks of the two techniques to guide researchers in deciding which method to use. Protocols and examples are given for measuring O ₂ evolution rates and for determining the number of chlorophyll molecules per active photosystem II reaction center.