pH activated fluorescent probes

Fluorescent probes activated by the environment they are in show tremendous promise for molecular imaging because of their improved specificity, and in turn, reduced autofluorescence from the background. This post highlights a paper from a Japanese group (Urano et al., Nature Medicine, Dec 2008) that shows imaging results of a fluorescent agent that, "is activated after cellular internalization by sensing the pH change in the lysosome." These probes potentially should be useful in optical fluorescence tomography, where small lesions can be missed because of autofluorescence effects.