Also found in: Medical.
(named for O. H. Warburg), an instrument (respirometer) for the determination of small quantities of gas at constant pressure and temperature; used in the investigation of processes that proceed with the liberation or absorption of gases—tissue respiration, fermentation, and individual fermentation reactions. The basic part of the Warburg apparatus consists of 12-14 small vessels that are hermetically connected to manometers by stopcocks; tissues or separate cell fractions that have been pulverized in a buffer-salt medium are placed in these vessels. The vessels are immersed in a water bath equipped with a heat-regulating device and a rocking mechanism. The quantity of gas liberated or absorbed is measured on a manometer.