A dual-signal output electrochemical immunosensor based on Au-MoS2/MOF catalytic cycle amplification strategy for neuron-specific enolase ultrasensitive detection

In this work, a dual-signal output electrochemical immunosensor based on the Au-MoS2/MOF high-efficiency catalytic cycle amplification strategy for the sensitive detection of neuron-specific enolase (NSE). The mixedvalence structure MOF (Fe2+/Fe3+-MOF) exhibits high-speed charge mobility and excellent electrochemical performance. Notably, nanoflowers-like MoS2 (MoS2 NFs), as a co-catalyst, were introduced into Fe2+/Fe3+-MOF to successfully ensure the stable cycle of Fe2+/Fe3+ at the electrode interface. The constantly emerging of fresh active sites significantly amplified the current signal response. According to the electrochemical behavior, the catalytic cycle mechanism and electron transfer pathways between MoS2 and Fe2+/Fe3+-MOF were further discussed. The two output signals of a sample realized the self-calibration of the immunoassay results, which improved the reliability and sensitivity of the immunosensor. Under optimal conditions, the linear range was 1.00 pg/mL similar to 100 ng/mL, and the low detection limits were 0.37 pg/mL and 0.52 pg/mL. The results suggest that the as-proposed immunosensor will be promising in the biological analysis and early clinical diagnosis of cancer biomarkers.

Automated summary

A dual-signal output electrochemical immunosensor based on the Au-MoS2/MOF high-efficiency catalytic cycle amplification strategy was developed for the sensitive detection of neuron-specific enolase (NSE). The introduction of MoS2 as a co-catalyst ensured the stable cycle of Fe2+/Fe3+ and significantly amplified the current signal response. The immunosensor showed promising potential in the biological analysis and early clinical diagnosis of cancer biomarkers.