State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, 5625 Renmin Street, Changchun 130022, P. R. China.
J Mater Chem B. 2019 Sep 25;7(37):5669-5676. doi: 10.1039/c9tb01544b.
Because of their complex and evolving characteristics, burn wounds always need repeated treatments to gradually and specifically re-expose the wound for further care, which cause pain to patients and reinjury to newly formed tissues. Thus, it is highly desirable to remove wound dressings in a controllable, painless, noninvasive, and facile way. Herein, we synthesized a photocleavable polyethylene glycol (PEG) crosslinker, and prepared a series of hydrogels by mixing this cross-linker with glycol chitosan (GC) in different ratios. In situ gelation occurred within 2 min, which was beneficial for hydrogels to be injected to the wound site and cover irregular shapes. The hydrogels were destroyed upon exposure to UVA light, which was noninvasive and could spatiotemporally control their breakdown, leading to the on-demand, noninvasive, and controllable removal of the hydrogels. The hydrogels also showed good swelling, suitable mechanical properties and adhesive strength. Moreover, the cytotoxicity assay demonstrated the good cytocompatibility of the precursors and degradation products. This photo-triggered on-demand removal will provide a promising method to alleviate pain during dressing change and facilitate future wound care.
由于烧伤创面具有复杂和不断演变的特点，总是需要反复治疗，逐渐、有针对性地再次暴露创面以进行进一步的护理，这会给患者带来疼痛，并对新形成的组织造成再损伤。因此，以可控、无痛、非侵入性和简便的方式去除创面敷料是非常需要的。在此，我们合成了一种光可裂解的聚乙二醇（PEG）交联剂，并将其与不同比例的壳聚糖二醇混合，制备了一系列水凝胶。原位凝胶化在 2 分钟内发生，有利于水凝胶注射到创面部位并覆盖不规则形状。水凝胶在暴露于 UVA 光下会被破坏，这种方法是非侵入性的，可以时空控制其分解，从而实现水凝胶的按需、非侵入性和可控去除。水凝胶还具有良好的溶胀性、适宜的机械性能和粘附强度。此外，细胞毒性试验表明，前体和降解产物具有良好的细胞相容性。这种光触发的按需去除方法将为缓解换药过程中的疼痛提供一种很有前景的方法，并有助于未来的伤口护理。
