Isolation of bloodstream trypanosomes by sedimentation field-flow fractionation

An alternative procedure to isolate circulating blood trypanosomes is proposed using a recently developed separation method whose characteristics are similar to chromatography. Field-now fractionation is a family of elution separation methods in which trypanosomes are separated from the other blood cells by means of their size density and motility. Separation occurs while cells are flowed in a simple isotonic medium into a ribbonlike channel on which a perpendicular field acting on the species is applied. In the case described here, the field is multigravitational. Purified trypanosome samples can be obtained from mouse blood in 20 min, with 80% recovery. The isolation of trypanosomes from mouse biological. fluids is shown, as well as the possibility of extending this procedure to the diagnosis of human sleeping sickness or cattle trypanosomiasis. (C) 1997 John Wiley & Sons, Inc.