1 SST/2.0 mL serum. After 30 minutes of clotting, promptly centrifuge and refrigerate serum.
Refrigerated: 24 hours; Frozen: 1 year
Troponin I is used as a cardiac marker. It can be detected at 4 to 8 hours following onset of chest pain with peak concentrations at 12 to 16 hours, and remains elevated for 5 to 9 days, providing more opportunity for detecting myocardial infarction or excluding the diagnosis.