Osmometers, Freezing Point
Definition : Osmometers designed for indirect determination of a solution's osmotic pressure (i.e., osmolality), a variable related to the particle concentration in the solution, by measuring the freezing point depression of the solution relative to the freezing point of a standard solution (e.g., sodium chloride) of known osmolality, based on one of the colligative properties of solutions. These instruments typically consist of a sample chamber with an operating head that includes a stirrer and a temperature sensor, a refrigeration device, and a display. Freezing point depression osmometers are intended for the determination of total solute levels that affect water balance in tissues and the gathering of information about water and electrolyte imbalances. An abnormal ratio between the osmolality in urine and serum may indicate renal disease, diabetes insipidus, or secretion of abnormal levels of antidiuretic hormone; water and electrolyte imbalances are also present in patients with acute poisoning and shock trauma.
Entry Terms : "Freezing Point Osmometers" , "Cryoscopes"
UMDC code : 23793