Fluorescence Imaging of Tumors with “Smart” pH-Activatable Targeted Probes
One goal of molecular imaging is to establish a widely applicable technique for specific detection of tumors with minimal background originated from non-target tissues. In this study, a “smart” activatable strategy for specific tumor imaging is proposed in which pH-activatable targeted probes specifically detect tumors after binding to the target cell surface proteins, internalization, and eventual acidic pH activation within the acidic organelles. We successfully visualized submillimeter-sized tumors using this strategy in two different tumor mouse models. Since the design of pH-activatable targeted probes can be applied to any target molecules on the cell surface that are to be internalized after ligand binding, this imaging strategy can afford a general and powerful method to diagnose and monitor the target tumors.
KeywordsOptical tumor imaging fluorescence molecular probes pH receptor-mediated endocytosis
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