EXPAR and Au–Ag mushroom-shaped SERS probe assisted detection of exosomal miR-375 in prostate cancer

Abstract

Exosomes carry abundant bioactive substances from parent cells, which contain tremendous amounts of proteins and nucleic acids and can be used as important diagnostic markers of diseases. In this work, we developed an EXPAR and Au–Ag mushroom-shaped SERS probe assisted strategy for the detection of exosomal miR-375 in prostate cancer. The EXPAR was triggered by the target miRNA and the amplification products were detected by the Au–Ag mushroom-shaped SERS tag, thus realizing the sensitive detection of miRNA. Prostate-specific membrane antigen (PSMA) positive exosomes captured by magnetic beads were released and lysed. This method was used to detect the concentration of miR-375 in PSMA-positive exosomes. The limit of detection was 10 fM. This method was also successfully employed to distinguish clinical serum samples from healthy people and prostate cancer patients, and has great potential application in the clinical diagnosis of prostate cancer.