Bioactive apelin peptide forms ranging in length from 12 to 55 amino acids bind to and activate the apelin receptor (AR or APJ), a Class G-protein coupled receptor. Apelin-12, -17, and -36 isoforms, named according to length, with an additional N-terminal cysteine residue allowed for regiospecific and efficient,conjugation of pyrene maleimide. Through steady-state fluorescence spectroscopy, the emission properties of pyrene in aqueous,buffer were compared to those of the pyrene apelin conjugates both without and with zwitterionic or anionic micelles. Pyrene photophysics are consistent with an expected partitioning into the hydrophobic micellar cores, while pyrene apelin conjugation prevented this partitioning. Apelin conversely, is expected to preferentially interact with anionic micelles; pyrene apelin conjugates appear to lose preferential interaction. Finally, Forster resonance energy transfer between pyrene and tryptophan residues in the N-terminal tail and first transmembrane segment (the AR55 construct, comprising residues 1-55 of the AR) was consistent with efficient nonspecific pyrene apelin conjugate binding to micelles rather than direct, specific apelin-AR55 binding. This approach provides a versatile fluorophore conjugation strategy for apelin, particularly valuable given that even a highly hydrophobic fluorophore is not deleterious to peptide behavior in membrane-mimetic micellar systems.