Electrochemical aptasensor for sensitive detection of Cardiac troponin I based on CuNWs/MoS2/rGO nanocomposite

Abstract

Cardiac troponin I (cTnI) is a “gold standard biomarker” for clinical diagnose of acute myocardial infarction (AMI). Rapid, accurate, and sensitive detection methods for cTnI are highly urgent and significant in early diagnosis and progression control. In this work, we proposed an electrochemical aptasensing platform for cTnI detection based on copper nanowires/molybdenum disulfide/reduced graphene oxide (CuNWs/MoS2/rGO) ternary nanostructure. The CuNWs/MoS2/rGO composite exhibited improved electrochemical activity due to the high electrochemical conductivity and the synergistic effect among each component, and the large surface area, which also facilitates the immobilization of aptamers. As a result, the constructed electrochemical cTnI aptasensor shows good selectivity, stability, and reproducibility towards cTnI. Under optimized conditions, the aptasensor responses cTnI linearly from 5.0 × 10−13 to 1.0 × 10−10 g mL−1 with a detection limit of 1.0 × 10−13 g mL−1 (S/N = 3). The analysis of cTnI in human blood samples demonstrated its practicability with comparable results. This work offers an alternative way for facile fabrication of CuNWs/MoS2/rGO based aptasensor for clinical biomarker detection.