Highly-Sensitive Implantable NIR Phototransistor for One-Click Pain Relief Activation

The increasing prevalence of chronic neuralgic pain in expanding populations has created urgent demands for robust pain relief technology. Their sporadic and unpredictable nature, however, presents significant challenge for on-demand inhibition of nerve transduction. Here, implantable near-infrared pain relief controllers are reported that leverage stretchable organic phototransistors with IDTBT/Y6 bulk-heterojunction, offering high responsiveness and reduce charge trapping to trigger detectivity of up to 9.4 × 10¹³ Jones. By integrating the device with an oscillating circuit, the 808 nm NIR irradiation with varying light intensities can trigger inhibiting voltage ranging from 1 kHz to 50 kHz. This allows for one-click precise manipulation of neural activity in rat sciatic nerves, achieving up to 99.4% signal suppression within just 20 milliseconds. Furthermore, the nearly real-time elimination of pain sensation is confirmed by measuring the amplitude of hind paw reflex movements of rats. These findings pave a novel way for the development of advanced pain relief systems for medical applications.