Multifunctional microfluidic-directed polymer/hydrogel fabrics towards pH-responsive drug delivery, wound monitoring...

Delayed skin wound healing caused by bacterial infection and persistent oxidative stress has been considered as a frequently encountered clinical problem that significantly affects patients' health. However, the real-time monitoring and on-demand treatment of non-healing wounds remain a great challenge. Herein, a feasible strategy is developed to core-shell polymer/hydrogel microfibers by integrating microfluidic spinning with shear-flow-induced coating technology. The fabricated self-healing microfibers are facilely assembled into nonwoven fabrics through reversible physical interactions. The core polycaprolactone (PCL) acting as a skeleton endows fabrics with structural and mechanical robustness (4.67 MPa), while the hydrogel shell brings functional diversity including great flexibility, self-healing, self-adhesion and pH-responsive swelling capability. By introducing epigallocatechin gallate (EGCG) in core PCL phase, the remarkable reactive oxygen species (ROS) cleaning capacity (93.8 % for 0.5 h) and antibacterial activity against E. coli (98.7 %) and S. aureus (99.6 %) are achieved. Particularly, the pH-regulated drug release of fabric in a prolonged form is achieved owing to the reversibly swelling/shrinking behavior of hydrogel shell with the changed environmental pH, which is expected to realize on-demand drug delivery and treatment of wound. Additionally, the pH-responsive curcumin-loaded mesoporous microparticles are incorporated into hydrogel shell, aiming to visually real-time detect pH level in a high-efficiency and reversible manner. Moreover, the fabric can serve as a flexible wearable sensor for precisely monitoring motions of patients. This strategy explores a feasible solution to diligently tracking wound pH and movements, along with inhibiting wound infection, substantiating a great foundation for application in personalized, intelligent and precise theranostic wound dressings.