• 3 mL plasma in a Lavender BD Hemogard™ K2EDTA Tube
Note: Draw two tubes to ensure adequate volume.
• Minimum volume: 1 mL
• Patient Preparation: Fasting specimen preferred.
Centrifuge the tubes, then transfer plasma into a standard aliquot tube before freezing the specimen.
• Transport Temperature: Frozen
Melatonin concentration varies with light and dark cycles: concentration is lower during the day and higher at night.Patients treated with pituitary or steroid hormones influence the concentration. Hormones should be discontinued for two days prior to collection.