osmometer
Introduction
Freezing point depression osmometry is the most commonly used method for determining osmolality of a solution. A freezing point osmometer consists of a sample chamber containing a stirrer & a thermistor connected to a readout device. The sample is rapidly cooled to several degrees below its freezing point in a chamber. The sample is then agitated with a stirrer to initiate crystal formation. As ice crystals form, the heat of fusion is absorbed by the supercooled solution in the sample chamber. The temperature of the partially frozen sample rapidly reaches equilibrium at the freezing point of the solution & stays at that temperature for several minutes. The freezing point is detected by the thermistor & the osmolality of the solution displayed in units of milliosmoles/kg H2O.
More general terms
Additional terms
References
- ↑ Clinical Diagnosis & Management by Laboratory Methods, 19th edition, J.B. Henry (ed), W.B. Saunders Co., Philadelphia, PA. 1996, pg 61