i3S-Instituto de Investigação e Inovação em Saúde, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal.
INEB-Instituto de Engenharia Biomédica, Universidade do Porto, Rua Alfredo Allen 208, 4200-135 Porto, Portugal.
Int J Mol Sci. 2022 Feb 19;23(4):2312. doi: 10.3390/ijms23042312.
Blood-contacting devices are increasingly important for the management of cardiovascular diseases. Poly(ethylene glycol) (PEG) hydrogels represent one of the most explored hydrogels to date. However, they are mechanically weak, which prevents their use in load-bearing biomedical applications (e.g., vascular grafts, cardiac valves). Graphene and its derivatives, which have outstanding mechanical properties, a very high specific surface area, and good compatibility with many polymer matrices, are promising candidates to solve this challenge. In this work, we propose the use of graphene-based materials as nanofillers for mechanical reinforcement of PEG hydrogels, and we obtain composites that are stiffer and stronger than, and as anti-adhesive as, neat PEG hydrogels. Results show that single-layer and few-layer graphene oxide can strengthen PEG hydrogels, increasing their stiffness up to 6-fold and their strength 14-fold upon incorporation of 4% (40 mg/mL) graphene oxide. The composites are cytocompatible and remain anti-adhesive towards endothelial cells, human platelets and , similar to neat hydrogels. To the best of our knowledge, this is the first work to report such an increase of the tensile properties of PEG hydrogels using graphene-based materials as fillers. This work paves the way for the exploitation of PEG hydrogels as a backbone material for load-bearing applications.
与血液接触的装置在心血管疾病的治疗中变得越来越重要。聚乙二醇（PEG）水凝胶是迄今为止研究最多的水凝胶之一。然而，它们的机械强度较弱，这限制了它们在承重生物医学应用（如血管移植物、心脏瓣膜）中的使用。具有出色机械性能、极高比表面积和与许多聚合物基质良好相容性的石墨烯及其衍生物是解决这一挑战的有前途的候选材料。在这项工作中，我们提出将基于石墨烯的材料用作 PEG 水凝胶的纳米增强剂，从而获得比纯 PEG 水凝胶更硬、更强且具有抗黏附性的复合材料。结果表明，单层和少层氧化石墨烯可以增强 PEG 水凝胶，将其刚度提高 6 倍，将其强度提高 14 倍，而氧化石墨烯的含量为 4%（40mg/mL）。这些复合材料具有细胞相容性，并且与纯水凝胶一样，仍具有抗内皮细胞、人血小板黏附的特性。据我们所知，这是首次使用基于石墨烯的材料作为填充剂来提高 PEG 水凝胶拉伸性能的工作。这项工作为将 PEG 水凝胶用作承重应用的基础材料铺平了道路。
