EVALUATION OF A TURBIDIMETRIC PROCEDURE FOR APOLIPOPROTEINS-A1 AND APOLIPOPROTEINS-B ON THE CIBA CORNING 550 EXPRESS

We evaluated a turbidimetric method for the estimation of apo A1 and a po B on the Ciba Corning 550 EXPRESS using Ciba Corning reagents. Inte rference due to bilirubin, hemoglobin, lipemia, triglycerides, and ure mia was minimal, with apolipoproteins (apo) A1 and B results usually w ithin +/-4% of expected values. Within-run and day-to-day imprecision (coefficients of variation) ranged from 1.96 to 3.60% and 2.63 to 3.39 % for apo Al and 1.02 to 1.740/. and 2.08 to 3.660/. for apo B, respec tively. Accuracy was determined by participation in the IFCC apolipopr otein standardization project in which results obtained on 50 patient samples were compared to those obtained by the reference laboratory. A po Al and apo B showed an average bias of +3.7% and +2.0% and correlat ion coefficients of 0.986 and 0.977, respectively. Results were also c ompared to those obtained on the Behring Turbitime system and showed a bias of +7.5% and -8.8% for apo A1 and apo B, respectively. The Ciba Corning automated method was rapid and gave good accuracy, precision, linearity, and parallelism and was relatively unaffected by raised tri glyceride values.