Recent Advances in Activatable Probes for Molecular Imaging by Stimuli‐Controlled Disassembly

Abstract

Comprehensive SummaryStimuli‐controlled disassembly process has shown promise to direct delivery of probes and/or spatial‐temporally control imaging signals for molecular imaging in vivo. Via the disassembly process, well defined nanoprobes with a stimulus‐responsive moiety can be controllably converted into small‐molecular imaging agents in response to a stimulus, leading to a switch in imaging signals. Moreover, the on‐site released small‐molecule probes could enhance penetration into the deep tissue for improved imaging of deep‐seated molecular targets. Therefore, such a stimuli‐controllable disassembly approach has been widely utilized to build activatable molecular imaging probes for the noninvasive detection of various molecular targets in living subjects. In this review article, we first briefly introduce the general principle of stimuli‐controlled disassembly. We then summarize the activatable probes based on different internal or external stimulus that has been utilized to control disassembly process. Activatable probes by using multiple stimuli to control cascaded in situ self‐assembly and disassembly processes are also discussed. Finally, we close with a conclusion of current challenges and perspective in this field. We wish this review paper will give readers useful information on molecular imaging via the intelligent stimuli‐controlled disassembly process.

Stimuli-instructed sequential morphological transformations for molecular imaging

“…In addition, physical (e.g., co-assembly) or chemical (e.g., chemical integration) modifications of peptide molecules are relatively easy to carry out, leading to controllable imaging properties. 27 Considering that earlier reviews have summarized stimuli-triggered morphological transformation of peptide-based probes, [28][29][30] in this review, we focus mainly on dual stimuli-instructed cascade self-assembly and disassembly or tandem selfassembly of peptide-based probes for molecular imaging (Fig. 1), which enables precise and sensitive imaging or efficient theranostics and provides multiple types of information about diseases.…”