Evaluating a Membrane Based Rapid Plasma Separation Device (RPSD) for Immunoassay Point-of-Care Testing (POCT) for Estimations of Cortisol, D-Dimer, Myoglobin and Thyroxine

Abstract

It has been shown that plasma derived from Rapid Plasma Separation Device (RPSD) is comparable to plasma obtained by centrifugation for immunological (HBsAg, HCV) and biochemistry (uric acid, urea, glucose) applications, with minimal white cell and platelet contamination but there is currently no published data for hormones. The aim of this study was to evaluate the integration of the RPSD into a Point of Care i-CHROMA™ quantitative immunoassay system comparing plasma separated using the RPSD's and plasma separated by centrifugation for estimations of cortisol, d-dimer, myoglobin and thyroxine. We conclude that the d-dimer, myoglobin and thyroxine estimations from the plasma derived from the RPSD-450 were not comparable with an unacceptable bias to the counterpart estimations from centrifuged plasma. However, the cortisol estimations were comparable and had an acceptable bias to the cortisol estimations from plasma separated by centrifugation on the immunoassay point of care i-CHROMA™ Cortisol method. Therefore the RPSD-450 could potentially be used in near patient testing situations where liquid plasma is required for the quantitative analysis of cortisol.