10 mL (5 mL min.) aliquot of 24-hour Urine collected in an acid washed (metal free) container kit available from TrueMedix. Mix thoroughly. Transfer 10 mL aliquot to vial provided in the kit. Measure 24 hour total volume and record on vial and test request form. Ship refrigerated or frozen. Patients should refrain from vitamins, mineral or herbal supplements one week prior to specimen collection. Use powderless gloves during specimen collection. If Gadolinium or Iodine containing contrast media has been administered, the specimen should not be collected for 96 hours.