An injectable, leadless bioelectronic interface for battery-free wireless peripheral neuromodulation

Injectable bioelectronics offer a minimally invasive approach to peripheral nerve stimulation but remain limited by onboard energy storage and fragile leads. Here, we present SEED, a leadless, battery-free bioelectronic interface engineered for percutaneous delivery through a standard 14-gauge needle. SEED (Stimulating Electrode for Electroceutical Delivery) operates in the magnetoquasistatic regime using low-frequency (65 kilohertz) resonant inductive coupling, externalizing waveform generation and control, enabling programmable neuromodulation without onboard active electronics. A spiral-helix electrode geometry promotes longitudinal nerve engagement while limiting off-target field spread. Benchtop and ex vivo characterization demonstrates precise, programmable control of stimulation frequency, pulse width, and amplitude under physiologically relevant conditions. In vivo validation in a rat sciatic nerve model confirms frequency-locked motor responses and graded neural recruitment following percutaneous deployment. SEED exhibits strong radiopacity and acoustic contrast, supporting compatibility with ultrasound and computed tomography for image-guided neuromodulation. This platform provides a scalable pathway toward minimally invasive bioelectronic therapies.