X.Y. Yi, Peng Deng, Zhou Wang, Jiawei Wang, Hongfei Wang, Zhanao Wu
Introduction Lung cancer prevalence rate has been rising steadily in recent years, for the prevention and treatment, the detection of tumor marker CYFRA 21-1 DNA demonstrates its significance. Methods In this work, an electrochemical biosensor was constructed for sensitive detection of CYFRA 21-1 DNA based on the novel developed Fe 3 O 4 /α-Fe 2 O 3 magnetic heterogeneous nanorods (MHNRs). Firstly, Fe 3 O 4 /α-Fe 2 O 3 MHNRs were prepared by hydrothermal-calcination method, and then Fe 3 O 4 /α-Fe 2 O 3 @Au magnetic nanocomposites (MNCs) were obtained though gold-coating. Subsequently, the magnetic self-assembling electrochemical biosensor based on Fe 3 O 4 /α-Fe 2 O 3 @Au MNCs was successfully constructed, which was verified by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). To optimize the biosensor’s experimental conditions and evaluate its performance, differential pulse voltammetry (DPV) was conducted. Results and Discussion The results showed that the detection range of CYFRA 21-1 DNA was 10 pM–10 μM, the limit of detection (LOD) was 1.5 pM. The biosensor exhibited excellent selectivity, reproducibility, and stability; the relative standard deviation (RSD) was 2.01%. The average recovery rate in the spiked diluted human serum samples was 101.4%, and the RSD was ≤5.2%, indicating that the biosensor possessed promising prospect.