E-Suture: Mixed-Conducting Suture for Medical Devices.

Area of Science:

• Biomedical Engineering
• Materials Science
• Neuroscience

Background:

• Implantable bioelectronics require soft, biocompatible materials for effective body integration.
• Efficient interfacing between biological ionic and external electronic charge carriers is crucial for advanced devices.
• Current technologies face challenges in achieving robust, low-impedance connections and multifunctional capabilities.

Purpose of the Study:

• To present a novel mixed-conducting suture, termed the e-suture, for advanced bioelectronic applications.
• To demonstrate the e-suture's capability for biopotential acquisition and drug delivery.
• To evaluate the long-term stability and performance of e-sutures in vivo.

Main Methods:

• The e-suture was fabricated using silk, poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS), and insulating polymers.
• Mechanical integration of e-sutures into electronic systems for biopotential recording (ECG, EMG, LFP).
• In vivo studies to assess chronic local field potential (LFP) acquisition and electrophoretic drug delivery.

Main Results:

• The e-suture exhibits mixed-conducting properties at the tissue interface and insulation along its length.
• Stable, chronic in vivo acquisition of LFP was achieved for months, showing robust brain activity patterns.
• Electrophoretic drug delivery was successfully demonstrated, offering targeted administration with a conducting interface for monitoring.

Conclusions:

• The e-suture is a versatile, soft, and biocompatible material for implantable bioelectronics.
• It expands the functionality of sutures beyond mechanical closure to include sensing, stimulation, and drug delivery.
• E-sutures offer a promising platform for advanced neural interfaces and therapeutic applications.