Click chemistry is a highly-selective and high-yield chemical approach which uses a wide scope of materials
and does not call for purification. Molecular imaging is an in vivo characterization and measurement of biologic processes
at the cellular and molecular level. Representative imaging modalities of molecular imaging are optical imaging, nuclear
imaging, and magnetic resonance imaging (MRI). Up to date, click chemistry has been widely employed by molecular
imaging to trap imaging probes on site and trace the biological events with high efficiency and high sensitivity. It has
played an important role in early detection of disease, real-time monitoring of drug delivery and investigating the functions
of biomolecules in vivo. Herein, we introduce the concept of click chemistry and illustrate the design of probes for
molecular imaging based on the strategies of click chemistry.