A microcytotoxicity assay using 111indium oxine release from platelets.

A simple, rapid method is described for the labelling of platelets with 111indium oxine for use in a microcytotoxicity assay. The assay described gives low levels of spontaneous lysis, good reproducibility and an end point may be determined by autoradiography as well as by direct measurement of release of 111indium. The labelled platelets, stored at 4 degrees C without further washing, may be used in the assay system for up to 4 days after preparation without loss of reproducibility.