LAUSR

With increasing knowledge of the diverse roles of exosomes in biological processes, much attention has been paid to the development of analytical methods for exosome analysis. Here, we developed a new class of amphipathic helical (AH) peptide-based fluorescent probes for highly sensitive detection of exosomes in a mix and read manner. Membrane curvature-sensing AH peptide (ApoC) was coupled with lipophilic tail (C12)-carrying thiazole red (TR) for construction of a self-assembly/disassembly based fluorescence "off-on" sensing system for target exosomes. ApoC-TRC12 has extremely weak emission due to the formation of the aggregates, whereas it becomes emissive in response to the target exosomes through the binding-induced disassembly of ApoC-TRC12. We demonstrated that the C12 unit attached to the TR unit had a favorable effect on both fluorescence response (signal-to-background: S/B) and binding affinity. ApoC-TRC12 was applicable to rapid and simple detection of exosomes with high detection sensitivity (limit of detection ≈ 103 particles/μL).