We used three methods to examine the relationship among intracellular pH, transmembrane potential, and extracellular pH. Single-barreled electrodes permitted the determination of resting potential and intracellular pH with a minimum of cellular injury. Double-barreled electrodes, which incorporated a reference as well as a pH-sensitive electrode in a single tip, facilitated the direct measurement of intracellular pH without the interposition of the transmembrane potential. Triple-barreled electrodes permitted measurement of intracellular pH during the controlled hyperpolarization or depolarization of the cell membrane.
Norman W. Carter, Floyd C. Rector Jr., David S. Campion, Donald W. Seldin