Conclusion

Affibody-based biosensors have emerged as powerful devices for the sensitive and specific detection of cancer biomarkers, offering remarkable potential across a wide range of diagnostic applications. This technology exhibits exceptionally high sensitivity, with very low LODs, making it ideal for clinical diagnostic use. The integration of affibody molecules into both electrochemical and optical sensing platforms has significantly enhanced the overall performance of these biosensors.

This review highlights significant progress in the application of affibody-based biosensors for detecting various cancer biomarkers, including TNF-α, HER2, EGFR, CEA and AFP. Among the methods discussed, the electrochemical affibody biosensor developed by Baydemir et al. [69] stands out as one of the most effective, demonstrating high sensitivity and specificity for TNF-α detection. This method employs screen-printed carbon electrodes (SPCEs) and MBs as a support for affibody immobilization. The use of magnetic beads accelerates detection time and minimizes matrix effects, achieving a LOD as low as 0.038 ng mL-1. Furthermore, the optical affibody biosensor described by Zhang et al. [91] also offers excellent sensitivity and selectivity for detecting the CEA biomarker. This approach utilizes PEGylated gold nanoparticles (AuNPs) in a test strip format and achieves a LOD of 2.5 ng mL-1, surpassing the clinical threshold of 5 ng mL-1.

Despite these significant advancements, several challenges remain for the wide-scale implementation of affibody-based biosensors. Issues such as sensor stability, scalability, production efficiency and non-specific binding still require further optimization. Nevertheless, the progress achieved thus far underscores the tremendous potential of this technology to revolutionize molecular diagnostics and precision medicine. As research continues to advance, these biosensors are expected to become more accessible, more cost-effective and more reliable, ultimately serving as valuable tools for early disease detection, personalized therapy and global health monitoring.