A type of magnetically induced self-assembled electrochemical aptamer nanobiosensor for ultrasensitive detection of hypoxia-inducible factor 1α protein.

BACKGROUND: Hypoxia-inducible factor 1α (HIF-1α) protein has been identified as an aggressive malignant phenotype marker for numerous tumors; therefore, the detection of HIF-1α has become increasingly significant. METHODS: In this work, we developed a type of magnetically induced self-assembled electrochemical aptamer nanobiosensor for detecting HIF-1α protein. This nanobiosensor utilized the magnetism of hydrothermal-calcination-synthesized α-ferric oxide/ferriferrous oxide (α-Fe2O3/Fe3O4, αFO/FFO) magnetic heterogeneous nanorods (MHNRs) to realize magnetically induced self-assembly; further, gold nanoparticles (AuNPs) were used to reinforce the electron transfer capacity and realize secure immobilization of the aptamer via Au-S bonds. Finally, we adopted cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and differential pulse voltammetry (DPV) for the electrochemical characterization, condition optimization, and performance analysis of the nanobiosensor, respectively. RESULTS: The nanobiosensor revealed a favorable linear relation in the range of 0.1-1,000 ng/mL with a variance R2 of 0.995 and limit of detection of 0.112 ng/mL, excellent sensitivity, faithful reproducibility with a relative standard deviation (RSD) of 2.28%, reliable 13-d stability with an RSD of 1.71%, and accredited detection capacity for real samples with recoveries of 97.71%-107.47% and RSDs ≤ 3.47%. CONCLUSION: In this study, we developed a magnetically induced self-assembled electrochemical aptamer nanobiosensor for ultrasensitive detection of HIF-1α protein. The nanosensor delivers outstanding analytical performance with a facile assay strategy suitable for point-of-care testing, suggesting its promising prospects for clinical tests.