Two-in-One Sensing Platform for the Detection of Exosomes Based on Molybdenum Disulfide-Based Nanozymes

Abstract

Compared with single-mode detection strategies, multi-mode sensing strategies have attracted more and more scientists’ attention due to their higher detection accuracy and credibility. Herein, a two-in-one sensing platform was designed for human breast cancer cell line (MCF-7)-derived exosomes detection by coupling the high catalytic activity of gold-platinum core-shell nanoparticles-decorated molybdenum disulfide nanozymes (MoS2-Au@Pt) with the specific recognition ability of aptamers (Apt). Probe DNA1 (P1) was assembled on the surface of MoS2-Au@Pt nanozymes to form signal amplified nanoprobes (MNP), which can efficiently catalyze 3, 3', 5, 5'-tetramethylbenzidine (TMB) and hydrogen peroxide reaction strategy to produce distinct electrochemical and colorimetric responses. The added target exosomes preferentially bound with anti-CD63 aptamer, leading to the dissociation of the “probe DNA2-Apt-MNP” sandwiched structure and the release of MNP from the electrode surface. Correspondingly, both electrochemical signal and solution color were reduced. According to this interesting sensing principle, the developed electrochemical/colorimetric dual-mode aptasensor showed excellent sensitivity, specificity and low detection limit for exosomes analysis. Furthermore, this dual-mode aptasensor can determine exosomes in human serum with accepted results, suggesting that the developed dual-mode detection strategy is a promising sensing method for accurate, sensitive and selective analysis of biomarkers in clinical samples.

Keywords: MoS2-Au@Pt, Nanozymes, Electrochemical, Colorimetric, Dual-mode, Exosomes