Development of a novel neodymium compound for in vivo fluorescence imaging.

We developed a novel fluorescent probe that contains the neodymium(III) complex moiety and fluorescein moiety. This probe can emit long-lived near-infrared luminescence derived from a Nd ion through excitation of the fluorescein moiety with visible light (lambda(ex) = 488 nm, lambda(em) = 880 nm, lifetime = 2.3 micros). These results indicate the possibility of the probe as a candidate for in vivo fluorescence molecular imaging.