Metal-Induced Dispersion of Lipid Aggregates: A Simple, Selective, and Sensitive Fluorescent Metal Ion Sensor

A new metal ion sensor capable of detecting nanomolar concentrations (< 1 ppb) of Cu^(2+) is made from mixed vesicles of a novel pyrene‐labeled metal‐chelating ligand and distearoyl phosphatidylcholine. When copper is added, the fluorescence monomer intensity emitted at 377 nm greatly increases, while the intensity of light emitted at 470 nm decreases. This effect is probably due to the dispersal of the fluorescent lipid throughout the matrix upon metal binding and is depicted schematically below.