INSULIN, FREE AND TOTAL Mnemonic INSULIN F/T Specimen Collection Requirements Patient Preparation Fasting specimen preferred. Reference intervals established for fasting specimens. Collect Serum, one 4.0 mL gold (SST) top tube, also acceptable: Plasma, one 4.0 mL lavender (EDTA) top tube Handling Separate serum from cells and transfer 2.0 mL serum to aliquot tube. Frozen. Separate specimens must be submitted when multiple tests are ordered. Preferred Volume 2.0 mL Minimum Volume 1.1 mL Transport Frozen Rejection Criteria Heparinized specimens, sodium fluoride/potassium oxalate plasma, hemolyzed specimens Stability AFTER SEPARATION FROM CELLS: Ambient: 8 hours; Refrigerated: 1 week; Frozen: 1 month Testing Information Performed Mon, Wed-Sat Reported 3-4 days Method Quantitative Ultrafiltration/Quantitative Chemiluminescent Immunoassay Referral Lab ARUP (70155) Reference Values Reference Values Interpretation provided CPT Codes 83525, 83527 Last Updated: Thursday, March 14, 2019 12:50:51 PM Client Services: 503-413-1234