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Citrate Plasma Samples

Syringe Method

Draw citrate anticoagulant (3.8% Na citrate) into a plastic syringe and then perform venipuncture using a citrate-to-blood ratio of 1:9 as follows:

  • 0.3 mL citrate plus 2.7 mL blood = 3.0 mL total sample
  • 0.4 mL citrate plus 3.6 mL blood = 4.0 mL total sample
  • 0.5 mL citrate plus 4.5 mL blood = 5.0 mL total sample

Please note that citrate to whole blood ratio is critical.

Vacutainer Method

  • Use a vacutainer needle or vacutainer butterfly set to draw blood directly into a 3 or 5 ml sodium citrate vacutainer tube. A complete draw must be obtained.

Large Animal Samples

Use a vacutainer needle and draw blood directly into a 5 - 10 mL blue top (3.8% Na citrate) vacutainer tube. A complete draw must be obtained.

Laboratory Animal Samples

(Do not use the eye orbital vein or tail vein collection technique) Anesthesia (deep surgical plane) is necessary for blood collection. Suitable anesthetic agents include pentobarbital or ketamine/xylazine. Incise the body wall and peritoneum on the ventral midline in order to expose the abdominal aorta for needle puncture.

Place citrate anticoagulant (3.8% Na citrate) into a plastic syringe and then draw blood using a 22 or 23 gauge needle. The ratio of citrate-to-blood must be exactly 1:9 as in the following examples:

  • 0.1 mL citrate plus 0.9 mL blood = 1.0 mL total sample
  • 0.2 mL citrate plus 1.8 mL blood = 2.0 mL total sample
  • 0.3 mL citrate plus 2.7 mL blood = 3.0 mL total sample

Please note that citrate to whole blood ratio is critical.

Plasma separation and storage

  • Centrifuge whole blood in a plastic or siliconized glass tube for 1 min. in a microfuge or for 10 min. in a tabletop centrifuge.
  • Transfer plasma only into a plastic tube using a plastic pipet.
  • Store samples frozen (-70 to -40oC) until shipment.

Shipping requirements

  • Ship samples in a styrofoam box with cold packs.
  • Ship overnight to arrive next day morning or afternoon.
  • Wrap tubes to prevent breakage.
  • Dry ice (3-5 lbs) may be required for shipment of special studies
  • Please refer to the shipping page for detailed shipping information.

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