Comparison of cardiac troponin I levels in serum and sodium-citrate plasma using the ACCESS 2 immunoassay.

The aim of this study was to determine if sodium-citrate plasma is a suitable substitute for serum for cardiac troponin I (cTnI) measurement using the Beckman ACCESS 2 immunoassay. Linear regression analysis of cTnI levels in paired serum and sodium-citrate plasma samples from 80 patients provided a y-intercept of -0.0193 and a slope of 1.