Photoelectrochemical Nanofiber Ferritin Sensor with Integrated “Migrating-Destructing-Detecting” Capability

Abstract

Conventional photoelectrochemical (PEC) protein sensors typically rely on steric hindrance to reduce photoelectric signals; however, this photoelectron-reducing model inherently limits protein accumulation at the sensing interface, thereby reducing detection sensitivity. By contrast, this study introduces an ultrasensitive PEC nanofiber-based ferritin sensor that employs a signal-enhanced mechanism by constructing numerous Ag₂O/Ag heterojunction nanoreactors along the nanofibers. Hydrophilic closed-loop nanostructures simultaneously integrate the migrating-destructing-detecting methods of ferritin within a single nanoreactor, resulting in enhanced photoelectric signals. This PEC nanofiber ferritin sensor exhibits a wide linear range of 10⁻⁸–10² mg mL⁻¹ and superhigh sensitivity of 5 pg mL⁻¹. Building on this platform, an ion signal-enhanced response device is developed to facilitate rapid and precise monitoring of proteins across low, normal, and high ferritin levels, enabling precise assessment under various pathological conditions. These findings establish a robust framework for ferritin detection using PEC protein sensing technologies.