5 mL (3 mL min.) aliquot of random Urine. Do not use preservative. Ship refrigerated. DO NOT FREEZE.
Freezing point depression
Sample Daily by 3 pm; Report Same day
Osmolality is an index of solute concentration. It corresponds to urine specific gravity in non disease states. This assay assesses the concentrating and diluting ability of kidneys. Preferebly urine and serum osmolalities should be measured simultaneously.