Stretchable antibacterial hydrogel with sodium alginate, hydroxyethyl cellulose, and sodium lignosulfonate for stabilized MXene/liquid metal-based patient health monitoring

Despite notable advances in conductive hydrogel-based flexible sensors, achieving a synergistic combination of high mechanical robustness, reliable electrical conductivity, antibacterial activity, and biocompatibility remains a formidable challenge for long-term wearable health monitoring. Herein, we report a stretchable, antibacterial, and biocompatible ionic hydrogel constructed by integrating MXene@SA (sodium alginate) and LM@LS (sodium lignosulfonate)/HEC (hydroxyethyl cellulose) hybrid fillers into a poly(vinyl alcohol)/acrylic acid double-network matrix with dynamic borate ester bonds and choline chloride as a hydrogen-bond acceptor. These three bio-based macromolecules-sodium alginate for MXene dispersion, and hydroxyethyl cellulose/sodium lignosulfonate for liquid metal stabilization-enable uniform filler distribution and establish a synergistic "point-to-plane" conductive network. The resulting PACML hydrogel exhibits excellent mechanical performance (tensile strength of 180.8 kPa, elongation at break of 1352%, and toughness of 965.21 kJ/m3), high conductivity (3.65 S/m), and excellent cyclic stability (83.84% stress retention after 10 cycles at 500% strain). Antibacterial evaluation against Escherichia coli and Staphylococcus aureus reveals 90.61% and 94.41% bactericidal efficiency, respectively, primarily attributed to the sharp-edged MXene nanosheets and their surface functional groups. In vitro cytocompatibility tests using human dermal fibroblasts show abundant live cells with normal spindle-shaped morphology after 5 days of coculture, confirming excellent biocompatibility. As a wearable sensor, the PACML hydrogel reliably detects a wide range of human motions-from subtle motions to large joint flexions-and enables Morse-code communication for patients with speech or mobility impairments. Critically enabled by sodium alginate, hydroxyethyl cellulose, and sodium lignosulfonate, this hydrogel offers a promising platform for patient health monitoring, rehabilitation, and telemedicine.