Abstract：
In recent years, negative pressure wound dressings have garnered widespread attentions. However, it is challenging to drain the accumulated fluid under negative pressures for hydrogel dressings. To address this issue, this study prepared a chemical/physical duel-network PEG-CMCS/AG/MXene hydrogel composed by chemical disulfide crosslinked network of four-arm polyethylene glycol/carboxymethyl chitosan (4-Arm-PEG-SH/CMCS), and the physical network of hydrogen bond of agar (AG). Under near-infrared light (NIR) irradiation, the PEG-CMCS/AG/MXene hydrogel undergoes photothermal heating due to integrate of MXene, which destructs the hydrogen bond network and allows the removal of exudate through a mechanism mimicking the sweat gland-like effect of skin pores. The photothermal heating effect also enables the antimicrobial activity to prevent wound infections. The excellent electrical conductivity of PEG-CMCS/AG/MXene can promote cell proliferation under the external electrical stimulation (ES) in vitro. The animal experiments of full-thickness skin defect model further demonstrate its ability to accelerate wound healing. The conversion between thioester and thiol achieved with L-cysteine methyl ester hydrochloride (L-CME) can provides the on-demand dissolution of the dressing in situ. This study holds promises to provide a novel solution to the issue of fluid accumulations under hydrogel dressings and offers new approaches to alleviating or avoiding the significant secondary injuries caused by frequent dressing changes.
摘要：
近年来,负压伤口敷料引起了广泛的关注。然而,在负压下排出积聚的流体用于水凝胶敷料是具有挑战性的。为了解决这个问题，本研究制备了由四臂聚乙二醇/羧甲基壳聚糖（4-Arm-PEG-SH/CMCS）的化学二硫化物交联网络组成的化学/物理双网络PEG-CMCS/AG/MXene水凝胶，和琼脂(AG)氢键的物理网络。在近红外光（NIR）照射下，PEG-CMCS/AG/MXene水凝胶由于MXene的整合而经历光热加热，这破坏了氢键网络，并允许通过模仿皮肤毛孔的汗腺样效应的机制去除渗出物。光热加热效应还使得抗微生物活性能够防止伤口感染。PEG-CMCS/AG/MXene在体外电刺激(ES)下具有良好的导电性能促进细胞增殖。全厚度皮肤缺损模型的动物实验进一步证明了其加速伤口愈合的能力。用L-半胱氨酸甲酯盐酸盐(L-CME)实现的硫酯和硫醇之间的转化可以提供敷料的原位按需溶解。这项研究有望为水凝胶敷料下的流体积聚问题提供新的解决方案，并提供新的方法来减轻或避免频繁更换敷料引起的重大二次损伤。
