CuFe2O4@T-COF nanosphere-mediated biosensing platform based on DNA walker signal amplification strategy for ultrasensitive HPV detection

Human papillomavirus (HPV) infection represents a major global health concern due to its strong association with cervical cancer and other malignancies, underscoring the critical need for highly sensitive detection methods. In this study, an advanced photoelectrochemical biosensing platform was developed for ultrasensitive HPV detection. An In 2 S 3 -sensitized SnO 2 heterostructure substrate that dramatically enhances photogenerated charge separation efficiency, generating extremely significant photocurrent enhancement. Furthermore, a CuFe 2 O 4 @T-COF nanosphere serving as a multifunctional signal quencher through synergistic steric hindrance, competitive oxygen consumption and light absorption effects. Notably, an exonuclease III-powered DNA walker system enabling cyclic signal amplification through programmable target recycling. The biosensor demonstrates exceptional analytical performance, achieving a broad dynamic range of 10 −6 to 10 μmol/L with an ultralow detection limit of 1.37 × 10 −7  μmol/L. This breakthrough sensing platform not only provides a powerful tool for early HPV diagnosis but also opens new possibilities for developing next-generation biosensors with clinical-level sensitivity and specificity.