Troponin I (TnI) is the inhibitory subunit of troponin,the structural protein involved in the regulation of striated muscle contraction. Cardiac Troponin I (cTnI) is produced by cardiac muscle. Two other TnI isoforms (slow sTnI and fast sTnI) are produced by slow-twitch and fast-twitch skeletal muscles,respectively. cTnI has been considered as one of the most specific and sensitive markers of myocardial damage like acute myocardial infarction (AMI) for decades. Detection of cTnI in serum is widely accepted as a diagnostic tool in acute coronary syndromes. This antibody is specific to cTnI,but not cross-react with skeletal TnI.