The copper containing oxygen transport protein hemocyanin (Hc) is vital for the survival of many animals belonging to arthropodan and molluscan phyla. The functional units (FUs), which constitute a Hc molecule, each contain an active site with a pair of Cu atoms able to reversibly bind molecular oxygen. Phenoloxidases (POs), from which Hcs probably evolved, possess a similar active site with paired Cu atoms but, in contrast to Hcs, they oxidize phenolic substrates. Reports indicate that due to the active site similarity Hcs can be induced to carry out PO activity. That’s why Hc became an interesting subject to explore its latent PO activity. Another important property of Hc is the immunogenic potency, which has led to therapeutic applications. This incited us to further study the antigenicity of Hc and the origin of this property. This research work exploited several analytical and separation techniques concerning protein purification-characterisation, measurement of the PO activity, analyses of the glycopeptides and detection of immunogenicity (ELISA).