Abstract: The invention provides a method for assaying for troponin I in a sample such as serum, the method comprising a determination of the troponin I concentration in a sample using a standard preparation that comprises a complete native troponin complex. One exemplary assay for troponin I concentration according to the invention is an immunoassay. Further contemplated in the method is a step comprising contacting the sample with a Ca2+-binding agent. Another aspect of the invention is the standard preparation comprising a complete native troponin complex. Yet another aspect of the invention is a kit for use in the assay method comprising the standard preparation, a detectable label, and a troponin I binding partner, such as an anti-troponin I antibody. All aspects of the invention are usefully practiced using human materials, such as a human troponin complex, and/or human sources for samples.

Abstract: The object of the invention is an improved diagnostic immunoassay method for assaying troponin I in a serum sample, wherein the improvement comprises determining the human troponin I concentration in the sample using a standard, which comprises a complete native troponin complex. The sample can also be brought in contact with a Ca2+-binding agent.