Implantable and Degradable Wireless Passive Protein-Based Tactile Sensor for Intracranial Dynamic Pressure Detection

Implantable sensors normally require devices with excellent biocompatibility and flexibility as well as wireless communication. Silk fibroin (SF) is an ideal material for implantable electronic devices due to its natural biodegradability and biocompatibility. In this work, we prepared SF protein materials with different force/chemical properties through mesoscopic regulation, and realized full protein replacement from substrate to dielectric elastomer for implantable sensors, so as to achieve controlled complete degradation. In wireless tests simulating intracranial pressure, the SF-based all-protein sensor achieved a sensitivity up to 4.44 MHz/mmHg in the pressure range of 0-20 mmHg. In addition, the sensor is insensitive to temperature changes and tissue environments, and can work stably in simulated body fluids for a long time. This work provides a wireless passive, all-protein material solution for implantable pressure sensors.

Automated summary

In this study, an all-protein sensor based on silk fibroin (SF) was developed for implantable pressure measurement. The SF protein materials with different properties were prepared and used for substrate and dielectric elastomer replacement, achieving controlled complete degradation. The SF-based sensor showed a high sensitivity up to 4.44 MHz/mmHg in the pressure range of 0-20 mmHg, and demonstrated temperature and tissue environment insensitivity as well as long-term stability in simulated body fluids. This work provides a wireless passive, all-protein material solution for implantable pressure sensors.