Bioinspired Wound Dressing

“慢性伤口护理的创新一直不足，证明是一个重大的挑战，成功地治疗慢性伤口，由于他们无法像急性伤口迅速愈合。一些慢性伤口永远不会恢复，导致败血症或截肢。慢性创伤患者可能需要长期住院治疗，这给医疗保健服务带来了更大的压力。慢性创伤尚未完全了解，有一些重要的步骤在体内顺序进行愈合伤口，这些步骤是：稳态，炎症，增殖和重塑，但慢性创伤不会超过炎症阶段。水凝胶人们已经认识到，在潮湿的环境中，慢性伤口愈合得更好。水凝胶是三维亲水网络，可以合成设计以吸收钙。1000倍于其重量的水而不溶解。当膨胀时，它们能够模拟生物组织。它们具有敷料所需的大多数理想特性，特别是管理创面水分的特性，据信其冷却效果可显著减少与伤口相关的疼痛，实现气体交换，并且可以在不引起进一步创伤的情况下移除。由于这些原因，它们被用作干燥、腐肉或坏死伤口的敷料。互穿网络（IPN）水凝胶是含有两个或更多个交联聚合物单元的水凝胶，由于它们在溶胀时增加的强度和稳定性，它们在结构上更有利。它们对于生物医学用途特别感兴趣，因为它们与细胞外基质具有相似性，由于细胞含有许多蛋白质，IPN可以由许多聚合物单元组成，这些相似性使它们成为伤口敷料的优秀候选者，以帮助组织再生。项目目标在本项目中，我们建议设计一种敷料，以刺激细胞外基质（ECM）的合成，以促进增殖伤口愈合阶段的进展。ECM是异构的，在健康的环境中会不断更新。它由两种主要成分糖蛋白（纤连蛋白、蛋白聚糖、层粘连蛋白）和纤维蛋白（胶原蛋白、弹性蛋白）组成。ECM影响结缔组织的分化以及锚定和附着以增强愈合过程。因此，能够调节ECM活性的伤口敷料的设计是期望的目标。因此，在本项目中，建议进一步探索由具有模仿ECM潜力的聚合物网络组成的水凝胶基敷料的设计。使用合成材料将提供调整水凝胶的能力，以生产更坚固的伤口敷料，从而能够进行气体交换和吸收多余的伤口渗出液，而不损失结构完整性并使伤口愈合和进展超过炎症阶段。将开发一种具有成本效益的水凝胶，其由交联聚合物的互穿网络组成，在溶胀时提供足够的强度。将从天然或合成材料中选择合适的单体单元，以适应慢性伤口的愈合。将优化聚合过程，将评估的水凝胶的性质是平衡水含量（EWC）、机械和剥离强度、粘弹性和水蒸气吸附性质。"

"The innovations in chronic wound care have been inadequate, proving to be a significant challenge to treat successfully chronic wounds, due to their inability to heal quickly like acute wounds. Some chronic wounds never recover leading to sepsis or amputations. Patients with chronic wounds can require hospitalisation for long periods of time, which puts an increased strain on health care services.Chronic wounds are not completely understood, there are important steps that are carried out in sequence within the body to heal wounds, these are: homeostasis, inflammation, proliferation and remodelling but chronic wounds do not progress beyond the inflammation stage. HydrogelsIt has become recognised that chronic wounds heal better when maintained in a moist environment. Hydrogels are three-dimensional hydrophilic networks that can be synthetically designed to absorb ca. 1000 times their weight of water without solubilising. When swollen they are able to simulate biological tissue. They possess the majority of the ideal characteristics required of dressings, in particular that of managing the wound bed moisture, a cooling effect believed to considerably reduced the pain associated with the wound, enable gaseous exchange and can be removed without causing further trauma. For these reasons they are used as dressings for dry, sloughy, or necrotic wounds. One disadvantage, however, is that when swollen they lose structural integrity.Interpenetrating network (IPN) hydrogels are hydrogels that contain two or more cross-linked polymeric units, which are structurally more favourable due to their increased strength and stability upon swelling. They are particularly interesting for biomedical use, as they share similarities with the extracellular matrix, due to cells containing many proteins, IPN can consist of many polymer units, these similarities make them an excellent candidate for wound dressings to aid in tissue regeneration. Project aimIn this project we propose to design a dressing to stimulate extracellular matrix (ECM) synthesis to promote progress through the proliferation wound healing stage. The ECM is heterogeneous and in a healthy environment is constantly renewed. It consists of two main components glycoproteins (fibronectin, proteoglycans, laminin) and fibrous proteins (collagen, elastin). The ECM influences the differentiation as well as anchorage and attachment of connective tissue to enhance the healing process. The design of a wound dressing capable of regulating ECM activity is therefore a desirable objective. In this project, it is thus proposed that the design of hydrogel-based dressings consisting of polymeric networks with the potential to mimic the ECM are explored further.The use of synthetic materials will provide the ability to tune the hydrogel, to produce a stronger wound dressing, that enables gaseous exchange and absorption of excess wound exudate, without losing structural integrity and enabling the wound to heal and progress beyond the inflammatory stage. A cost-effective hydrogel will be developed that consists of an interpenetration network of crosslinked polymers, that provides adequate strength upon swelling. Appropriate monomer units, from natural or synthetic materials, will be selected to suit the healing of chronic wounds. The polymerisation process will be optimised, the properties of the hydrogel that will be assessed are equilibrium water content (EWC), mechanical and peel strength, viscoelastic properties and water vapour sorption properties. "