Dual signal output ratiometric biosensor platform with regulable nanofiber-mediated signal amplification strategy for ultrasensitive detection of tumor biomarker

It is of great significance for the early diagnosis of cancer to detect the tumor biomarkers in human blood. However, it is still challenging to develop easily available and cost-effective methods to detect the ultralow-level tumor biomarkers. In this work, an innovative signal amplification strategy was developed for the ultrasensitive detection of tumor biomarkers. Amphiphilic peptides with high self-assembly performance can self-assemble into regulable nanofibers and enrich fluorophore to amplify the signal, which can improve the sensitivity of detection. Meanwhile, the design of MOFs with higher fluorescence quenching efficiency and luminescence characteristics can realize double-signal output and further improve the accuracy and sensitivity of detection. Taking alpha-fetoprotein (AFP) as a model tumor biomarker, this strategy achieved a wide linear range of 1–40 ng/mL detection, reducing the limit of detection (LOD) from 9.02 ng/mL to 0.28 ng/mL compared with no signal amplification strategy. Significantly, the results of clinical samples detected by this strategy was consistent with chemiluminescence immunoassay used in clinical practice. Our work provides a brand-new idea for signal amplification strategy and shows an important application prospect in the early diagnosis of various diseases.