A Pollen-Enhanced Bionic Mechanoreceptor Induced by Asymmetric Ionic Convection in Hydrogel for Sensory-Augmented Prostheses.

The growing prevalence of age-related limb loss underscores the need for prosthetic technologies that restore not only motor function but also authentic sensory feedback. Current prosthetic systems largely depend on sensory substitution or signal remapping, which fall short of replicating natural somatosensory signals. In this work, we develop a plant-enhanced bionic mechanoreceptor that mimics biological touch by converting mechanical stimuli into ionic signals. Incorporating bio-derived pollen microgels into the hydrogel matrix introduces interfacial ion-anchoring sites that strengthen cation-matrix interactions, enhance ionic polarization, and significantly amplify the piezoionic output. This enhancement arises from pressure-driven asymmetric ion transport within the ionically conductive hydrogel. As a result, the output signal increases by up to 12-fold, providing a simple and accessible strategy to improve the sensitivity of piezoionic mechanoreceptors. Then, we demonstrate the integration of ten such mechanoreceptors into a robotic prosthetic arm and utilize a deep learning algorithm to interpret the complex signal patterns. The system achieves accurate recognition of object interaction, validating the potential for naturalistic tactile feedback. This platform offers a scalable, biomimetic solution for developing next-generation sensory-augmented prostheses and may inform future designs in neuroprosthetics and human-machine interfaces.