Bioelectronic sutures with electrochemical glucose-sensing for real-time wound monitoring

Real-time in situ monitoring of wound physiologic information in clinical practice is essential to assist healthcare professionals in assessing the status of a patient's wound and the healing process, with glucose levels recognized as a key factor in assisting healthcare professionals in assessing the status of a patient's wound. The form factor of planar flexible sensors limits them primarily to the skin surface and superficial wound areas, while fiber-based biosensors, due to their excellent flexibility and mechanical strength, can provide comfortable human-machine interfaces and thus have the potential to realize real-time monitoring of blood glucose levels in deep wounds of the skin. However, they still have drawbacks of being relatively single-function and requiring external power sources. Here, we innovatively propose bioelectronic sutures with glucose-sensing based on Fiber Biofuel Cells (Fiber BFC) for real-time in situ monitoring of glucose at wound sites. Fiber BFC utilized porous gold-plated cotton fibers (defined as "10-TAF") as base electrodes. The fiber anode was assembled with glucose oxidase (GOx) as the catalyst, tetrathiafulvalene (TTF) as the electron mediator for the catalysis of glucose molecules, and the fiber cathode was assembled with Pt NPs as the catalyst for the reduction of O₂. The results showed that Fiber BFC exhibited good flexibility and tensile strength (tensile deformation at break rate of 27 % and Young's modulus of 2795.41 MPa), with mechanical properties comparable to those of medical sutures, and possessed the ability to be steadily monitored in multifarious complex environments. In addition, the P_max of Fiber BFC remained above 90.4 % after 128 h of intermittent operation. By suturing at abdominal wounds of rats, it was shown that Fiber BFC possesses excellent glucose sensing properties (sensitivity of 9.25 mV mM^-1) and biocompatibility, and can be used as bioelectronic sutures for real-time monitoring of wounds, which is anticipated to replace traditional medical sutures in clinical applications.