In the luminol-O₂ ECL system, O₂ as an endogenous coreactant has the advantages of non-toxicity and stability. Improving the efficiency to generate radicals of O₂ 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-O₂ system. Specifically, high-intensity focused ultrasound (HIFU) pretreatment as a non-invasive method could generate ROS (H₂O₂, O₂^•−, OH•, ¹O₂) in situ, triggering and boosting the ECL signal of luminol. In addition, 1T/2H MoS₂ with excellent catalytic activity could catalyze the H₂O₂ produced 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.

在鲁米诺-O ₂ ECL体系中，O ₂作为内源性共反应物具有无毒、稳定等优点。提高O ₂自由基的生成效率是目前面临的挑战。在这项工作中，设计了一种结合物理方法-超声和具有独特物理化学性质的纳米材料的策略来增强鲁米诺-O ₂体系的ECL信号。具体而言，高强度聚焦超声 (HIFU) 预处理作为一种非侵入性方法，可以原位产生 ROS（H ₂ O ₂ , O ₂ ^•- , OH•, ¹ O _{2 ），触发和增强鲁米诺的 ECL 信号。}此外，1T/2H MoS具有优异催化活性的2可以催化原位产生的H ₂ O 2 ，​​加速鲁米诺的氧化，进一步增强_ECL响应_。同时，结合催化发夹组装（CHA）反应，构建的ECL生物传感平台对miRNA-155的检测表现出优异的性能。浓度范围为 0.1 fM ∼ 1 nM，检测限低至 0.057 fM。此外，ECL生物传感器还成功应用于人血清样品中miRNA-155的测定。已建立的 ECL 传感平台为检测临床生物标志物开辟了一种有前途的方法。