Hemocyanin linked to protein A as an immunochemical labeling reagent for electron microscopy

Hemocyanin-protein A (Hcy/A) is an immunochemical marker suitable for both transmission and scanning electron microscopy. A method is described for the preparation of highly monomeric Hcy/A where protein A and hemocyanin are present in the conjugate in a nearly equal molar ratio. Examples of Hcy/A labeling of several cellular antigens are provided.