Noninvasive and sensitive electrochemical biosensor for the detection of oral cancer overexpression 1 in saliva

Sensitive detection of oral cancer overexpressed 1 (ORAOV1) in saliva holds great promise for the noninvasive and early diagnosis of oral squamous cell carcinoma (OSCC). Herein, we present a label-free and sensitive electrochemical (EC) biosensor for the detection of ORAOV1 in saliva. UiO-66@Fe-DNA coordination polymers were formed through one-pot self-assembly of Fe-DNA hybrids on UiO-66. A dual amplification strategy integrating UiO-66@Fe-DNA coordination polymers with entropy-driven catalytic (EDC) reaction was employed to enhance detection sensitivity. Using a G-quadruplex/methylene blue (MB) complex as an electrochemical indicator, a label-free, high-sensitivity EC biosensor was effectively developed for ORAOV1 identification. The proposed biosensor demonstrated outstanding selectivity for ORAOV1, a wide linear range from 1 fM to 1 nM, and a low limit of detection (LOD) of 0.38 fM. Notably, our EC biosensor provided a new paradigm for the early, noninvasive, and accurate diagnosis of OSCC by precisely distinguishing oral cancer patients from clinical samples with excellent accuracy (AUC = 1).