Conductive hydrogels have risen as a promising material for flexible wearable sensors. However, achieving a hydrogel that simultaneously possesses high mechanical properties, conductivity, self-healing ability, and adhesion remains a challenge. Herein, we developed a dual-network ionic conductive hydrogel (P-P(C-A)-PA) by incorporating poly(vinyl alcohol) and a copolymer of catechol-modified ionic liquid and acrylamide. The optimized hydrogel exhibited outstanding mechanical performance (stress: 883 kPa, strain: 1120%), self-healing efficiency (stress recovery of 58.6% ± 4.6% and toughness recovery of 57.7% ± 5.5%), ionic conductivity (3.91 S/m), and adhesion strength (50 kPa on Ecoflex). The hydrogel-based flexible sensor reliably monitored human motion with rapid and accurate signal response even after self-healing. The hydrogel-based triboelectric nanogenerator showed excellent output performance (180 V, 7.9 μA, and 65 nC), further identifying grasped objects and monitoring finger rehabilitation before and after self-healing. These results highlighted the considerable potential of our hydrogel for applications in advanced electronics.
Jingjing Du, Xi-Xi Zhu, Zengsheng Wang et al.· Biomacromolecules· 0 citations
Wound status monitoring has emerged as a promising strategy to enable timely intervention for effective wound infection management and promote wound healing. Herein, a recyclable alginate hydrogel film with pH-sensing and antibacterial functions is developed as a smart wound dressing. The hydrogel film (SA-Anth) was fabricated via a two-step process, i.e., an evaporation-induced self-assembly of sodium alginate solution doped with anthocyanin and glycerin, followed by Ca2+-mediated ionic cross-linking using CaCl2. Taking advantage of the pH-responsiveness of anthocyanin, the hydrogel film exhibited distinct color changes from red-purple at pH 5.0 to violet-blue at pH 7.3 and further to green at pH 9.0, suggesting its potential for visual monitoring of wound pH variations associated with infection. The incorporation of anthocyanin endowed the film with antibacterial activity, achieving bacterial reduction rates of 90.48% against E. coli and 98.10% against S. aureus. The hydrogel film also exhibited wound-dressing-relevant properties, including appropriate physicochemical performance, a low hemolysis ratio, and good in vitro cytocompatibility. In an S. aureus-infected rat full-thickness wound model, SA-Anth treatment enhanced wound closure and improved histological features of tissue repair compared with the control treatments. Furthermore, the de-crosslinking of the ionically crosslinked network was triggered by the addition of EDTA, enabling the recovery of the alginate component. The SA-Anth hydrogel film integrates pH-responsive visual indication, antibacterial activity, favorable biocompatibility, infected-wound repair performance, and EDTA-assisted material recovery, providing a promising platform for intelligent wound-dressing applications.
Xi-Xi Zhu, Ying Feng, Hai-Qi Zhang et al.· International Journal of Bio...· 0 citations