Pancreatitis-Associated Extracellular Vesicle Identification through an Allosteric Probe-Initiated Cascade Amplification System

[Image: see text] As an emerging class of noninvasive biomarkers, accurate quantification of circulating extracellular vesicles (EVs) is essential to both the basic biological research and early diagnosis of pancreatitis. We report here an allosteric probe-initiated cascade amplification system for a highly sensitive detection of serum-circulating EVs. In this method, the special recognition of EVs by the allosteric probes triggers allosterism of the probe and thus induces the release of a signal amplification initiator. Through the following multiple rounds of cascade amplifications, a large number of fluorescence moiety are released, generating an enhanced fluorescence signal. This method exhibits a large dynamic range of 5 orders of magnitude. In addition, this strategy could also be performed under isothermal conditions in a wash-free way, indicating its potential applications in early diagnosis and prognosis of pancreatitis.