Boosting the electrochemiluminescence of luminol by high-intensity focused ultrasound pretreatment combined with 1T/2H MoS2 catalysis to construct a sensitive sensing platform

In the luminol-O2 ECL system, O-2 as an endogenous coreactant has the advantages of non-toxicity and stability. Improving the efficiency to generate radicals of O-2 is a challenge currently. In this work, a strategy combining physical method -ultrasound and nanomaterial with unique physicochemical properties was designed to enhance the ECL signal of luminol-O-2 system. Specifically, high-intensity focused ultrasound (HIFU) pretreat-ment as a non-invasive method could generate ROS (H2O2, O-2 center dot(<-) , OH center dot, 1O2) in situ, triggering and boosting the ECL signal of luminol. In addition, 1T/2H MoS2 with excellent catalytic activity could catalyze the H2O2 pro-duced in situ, accelerate the oxidation of luminol and further enhance the ECL response. At the same time, combined with the catalytic hairpin assembly (CHA) reaction, the constructed ECL biosensing platform showed excellent performance for the detection of miRNA-155. The concentration range of 0.1 fM - 1 nM with the detection limit as low as 0.057 fM were obtained. Furthermore, the ECL biosensor was also successfully applied to the determination of miRNA-155 in human serum samples. The established ECL sensing platform opens up a promising method for the detection of clinical biomarkers.

Automated summary

A strategy combining ultrasound and nanomaterial was designed to enhance the ECL signal of the luminol-O2 system. Ultrasound pretreatment generated ROS in situ and triggered the ECL signal, while 1T/2H MoS2 catalyzed the oxidation of luminol and further enhanced the ECL response. The ECL biosensor, combined with catalytic DNA assembly, showed excellent performance for the detection of miRNA-155 with a detection limit of 0.057 fM.