Research of exosome in bone metastasis through dual aptamer recognition based entropy-driven amplification.

Sensitive and accurate detection of exosome will greatly facilitate the early diagnosis of diverse diseases, such as cancers. Herein, a novel dual aptamer recognition based entropy-driven amplification was established for accurate analysis of exosomes. There are two main procedures in the proposed biosensor, including dual aptamer based recognition of exosome and entropy-driven catalytic system based signal recycling. In the recognition process, designed SMBs-S1 probe and S2-S4 probe complex, containing a CD63 aptamer and an EpCAM aptamer, respectively, are utilized for cooperated identification of exosomes. S4 probe was then released from S2-S4 probe complex through chain replacement of S5. The released S4 probe triggers entropy-driven catalytic system based signal recycling and endow the method a superior sensitivity. Impressively, owing to the cooperated identification of CD63 and EpCAM protein, the method exhibited a superior specificity and stayed stable under the interference of free CD63 and/or EpCAM protein. We believe that the sensitive, accurate strategy will provide a powerful tool for multiple biomarkers analysis and related clinical applications.