Sedimentation field-flow fractionation application to Toxoplasma gondii separation and purification

Toxoplasmosis is a worldwide disease caused by Toxoplasma gondii, an intrac ellular protozoa of micronic size range (4-10 mu m). Its classical purifica tion processes are complex and often associated with low recovery. All inve stigation procedures concerning this parasite require its isolation and pur ification from at least the mouse ascitic fluid. For this purpose, a recent ly developed laboratory technology was used, i.e. sedimentation field-flow fractionation. This chromatographic-like separation technology was demonstr ated to be particularly selective for isolation and separation of micron-si zed biological particles. Sedimentation field-flow fractionation operated o n the steric-hyper-layer mode was used to isolate the parasite from the rem anent ascitic contaminants of different origins and from red blood cells. W ith this technology, 86% recovery with 97% viability was obtained in less t han 30 min. (C) 1999 Elsevier Science B.V. All rights reserved.