1998 Volume 68 Issue 9 Pages 375-380
In order to establish a detection system for endotoxin in blood products, we investigated for a method for sample pretreatment optimal for limulus test. In measuring endotoxin in blood products, an aliquot of plasma was 10 times diluted with surface-active agent and heat-treated at 80℃ for the purpose of removing inhibitory effect on endotoxin activity derived from serum component. Treated sample was then allowed to endotoxin analysis using a toxinometer MT-358(Wako)that yielded 100% recovery of endotoxin added to blood products. However, endotoxin activity in red cell-MAP supernatant was completely lost after heat-treatment, rendering the pretreatment method inadequate for measurement of endotoxin in red cell-MAP. Impaired endotoxin activity, however, possibly caused by a heat treatment under a very low protein concentration, was found to be restored after diluting the sample 30-40 times with endotoxin-free water without heating, yielding a recovery of more than 90%.
