The use of horseradish peroxidase-lectin conjugates to monitor the purity of plasma-membrane preparations obtained from isolated cells.

The plasma membranes of viable murine EL4 tumour cells were labelled with horseradish peroxidase-conjugated wheat-germ agglutinin. After disruption of the labelled intact cells, plasma-membrane purification could be monitored by ultrastructural examination of the various fractions for positive reaction product on the membrane vesicles.