Electrochemical exosome detection system based on dual RCA amplification triggered by 4-WJ structure and detection method thereof

The invention discloses an electrochemical exosome detection system based on dual RCA amplification triggered by a 4-WJ structure, and belongs to the field of tumor detection. The electrochemical exosome detection system comprises a working electrode of an electrochemical sensor, the surface of a gold electrode is modified with nano-gold particles to increase the surface area of the gold electrode and facilitate combination with an aptamer 1, after the aptamer 1 captures a target exosome, the exosome is further combined with an aptamer 2 to form a sandwich structure, and the electrochemical exosome detection system is used for detecting the target exosome. According to the structure, the detection specificity can be remarkably improved through the dual aptamers. Then, the exponential amplification of a target signal is realized through a dual RCA system triggered by a DNA (deoxyribonucleic acid) four-way linkage structure (DNA source-way linkage, 4-WJ); finally, further amplification of electrochemical signal