Application of antimony microelectrodes to intracellular pH monitoring

Some novel studies of the properties of the antimony microelectrode used for intracellular pH measurements are described. First, it is shown that currents in the picoampere range, such as those encountered as leakage in some electrometers, induce important changes in pH sensitivity. The response time of the electrode has also been measured and indicates that the electrode exhibits a rapid time course which would be very useful for dynamic cytoplasmic pH investigations. An example of internal pH recording during cellular acidification in Xenopus laevis oocyte is also presented.