Mussel-Inspired Flexible, Wearable, and Self-Adhesive Conductive Hydrogels for Strain Sensors.

The latest generation of wearable devices features materials that are flexible, conductive, and stretchable, thus meeting the requirements of stability and reliability. However, the metal conductors that are currently used in various equipments cannot achieve these high performance expectations. Hence, a mussel-inspired conductive hydrogel (HAC-B-PAM) is prepared with a facile approach by employing polyacrylamide (PAM), dopamine-functionalized hyaluronic acid (HAC), borax as a dynamic cross-linker agent, and Li+ and Na+ as conductive ions. HAC-B-PAM hydrogels demonstrate an excellent stretchability (up to 2800%), high tensile toughness (42.4 kPa), self-adhesive properties (adhesion strength to porcine skin of 49.6 kPa), and good self-healing properties without any stimuli at room temperature. Furthermore, the fabricated hydrogel-based strain sensor is sensitive to deformation and can detect human body motion. Multifunctional hydrogels can be assembled into flexible wearable devices with potential applications in the field of electronic skin and soft robotics.

Efficient clearance of periodontitis pathogens by S. gordonii membrane-coated H2O2 self-supplied nanocomposites in a "Jenga" style.

As a key pathogen of periodontitis, P. gingivalis requires support of the initial colonizing bacterium (S. gordonii preferably) to form symbiotic biofilms on gingival tissues with enhanced antibiotic resistance. Here, we report a new strategy to treat periodontitis biofilms with S. gordonii membrane-coated H2O2 self-supplied nanocomposites (ZnO2/Fe3O4@MV NPs) in a "Jenga" style. Integration of our special MV coatings enables selectively enhanced internalization of the cargos in S. gordonii, thus inducing severe damage to the foundational bacterial layer and collapse/clearance of symbiotic biofilms consequently. This strategy allows us to clear the symbiotic biofilms of S. gordonii and P. gingivalis with active hydroxyl radicals (˙OH) derived from ZnO2-Fe3O4@MV NPs in a H2O2 self-supplied, nanocatalyst-assisted manner. This "Jenga-style" treatment provides a cutting-edge proof of concept for the removal of otherwise robust symbiotic biofilms of periodontitis where the critical pathogens are difficult to target and have antibiotic resistance.