Molecular imaging: design mechanism and bioapplications

Molecular imaging is a non-invasive method to image and analyze the concentration and activity of functional biomolecules in cells or in vivo at molecular level, and plays an increasing role in deep understanding of biological processes, early and accurate diagnosis of diseases, and evaluation of treatment. Nowadays, numerous novel molecular imaging probes have been developed, involving every biomedical imaging modality, such as optical imaging, photoacoustic imaging, magnetic resonance imaging, single-photon-emission computed tomography, and positron emission tomography. In this review, we summarize the development of current state-of-the-art molecular imaging probes. We introduce the design strategies of molecular probes and detailed imaging modalities, and highlight the properties of probes and biomedical imaging applications in cells and in vivo , including disease diagnosis, drug tracking, and imaging-guided surgery. Then we discuss the perspectives and challenges in this emerging field. We expect this review could inspire more effective molecular imaging probes to be developed, achieving the goal towards clinical practices.