Differentiation of isozymes of an enzyme is important for the diagnosis of various diseases.  However, due to the marked similarity of the active sites and homology of primary structures, this differentiation is a challenging task. We prepared polymerized liposomes incorporating an inhibitor and chelated Tb³⁺ and Eu³⁺ ions as lipid headgroups. A polymerizable lipid with chelated Cu²⁺ ions was also included in the liposomal formulations to facilitate the interactions with proteins. We observed that in the presence of recombinant human carbonic anhydrase isozymes, there were significant increases in sensitized emission intensity of the lanthanide ions as well as in the excited state lifetimes. We found that the changes in the luminescence of either of the lanthanide ions are specific for particular isozymes. Combination of the observed parameters for both lanthanide ions provides an accurate and efficient method for differentiation of the isozymes of carbonic anhydrase.