Exo-III Enzyme and DNAzyme-Assisted Dual Signal Recycles for Sensitive Analysis of Exosomes by Using Personal Glucose Meter

Exosome plays a crucial role in regulating intercellular communication during atherosclerosis development. However, sensitive and portable exosome detection remains a huge challenge. Herein, a personal glucose meter (PGM)-based exosomes detection approach has been proposed that allows detection of exosomes with a high sensitivity and reproducibility. In this method, a catch probe, which is composed of CD63 aptamer and blocker sequence, is utilized for the specific identification of exosomes. The blocker sequence binds with H probe to initiate the Exo-III-assisted signal recycles to generate numerous DNAzyme sequences. Under the assistance of the substrate, DNAzyme forms its active secondary structure to generate gap site in substrate, releasing a linker to conjugate sucrase to streptavidin magnetic beads (SMBs). After removing unbound sucrase, the SMB-linker-sucrase complex is used to catalyze sucrose to glucose, which can be read by PGMs. Based on this, the method exhibits a wide detection range and a low limit of detection, holding a promising prospect for the analysis of exosomes and screening atherosclerosis. Graphical abstract