The Cytosensor Microphysiometer detects cellular responses to a wide variety of effector agents by measuring the rate of
acidification with a silicon sensor. Cells are sandwiched between two porous membranes inside disposable capsules, and are supplied with a controlled flow of culture medium. Effector agents of interest can be introduced in the cell chamber, and
incubated for a defined period of time. Modifications in the metabolic activity of the cells result in changes in the rate of
excretion of acidic products, altering the surface charge of the light addressable potentiometric sensor. This variation is
reported by the Cytosensor system as a signal change compared to the basal acidifcation rate.
 

Microphysiometry monitors the change in extracellular pH of cells contained in a small volume (1.4 L). The Cytosensor
Microphysiometry system thus provides a means for determining the membrane receptor-mediated response profiles of viable cells to defined dosing schedules of a variety of effector agents. These agents include agonist and antogonists of
neurotransmitter, hormone, cytokine and growth factor receptors, signal transduction probes and a variety of other proteins
and peptides. The Cytosensor measures the changes in extracellular acidification rate resulting either from alterations in teh
energy demand made on cells as they respond to the effector agents of from alterations in sodium-hydrogen exhange across the cell membrane during homeostatic control of intracellular pH.