Oregon Green^™488 is a fluorinated fluorescein dye.^1,2It exists as a tautomer in aqueous solutions.²Oregon Green^™488 has minimal pH dependence at physiological pH but it can be used as an indicator for intracellular pH due to its low pKa of 4.8.^2,3It is less susceptible to photobleaching than fluorescein. Oregon Green^™488 has been conjugated to antibodies and proteins, as well as DNA, for use in labeling and detection.^2,4,3It displays excitation/emission maxima of 490/514 nm, respectively.¹

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