A new chemical strategy is described to link ethylenediamino (EDA) groups to primary hydroxyl groups of hyaluronic acid (HA) and the obtained derivatives have been characterized by 1H-NMR and 13C-NMR analyses. Such HA–EDA derivatives have been exploited to control the functionalization degree in benzoyl-cysteine (BC) groups, chosen as moieties able to allow both self-assembling in aqueous media and an oxidative crosslinking. In particular, the kinetics of oxidation of thiol groups in HA–EDA–BC derivatives has been studied in Dulbecco's Phosphate Buffer Solution (DPBS) pH 7.4 by colorimetric assays and rheological measurements. Mechanical properties of chemical hydrogels obtained after oxidative crosslinking have been evaluated by using two different concentration values (1 and 1.5% w/v) of HA–EDA–BC. These hydrogels show a dense interconnected fibrillar structure similar to the extracellular matrix of soft tissue and a resistance to chemical and enzymatic hydrolysis. Therefore, the potential suitability of HA–EDA–BC hydrogels as scaffolds for cartilage regeneration has been preliminarily assessed using primary human chondrocytes and evaluating their viability and ability to produce extracellular collagen.
本文介绍了一种将
乙二胺(E
DA)基团与透明质酸(HA)的伯羟基相连接的新
化学策略,并通过 1H-NMR 和 13C-NMR 分析对所获得的衍
生物进行了表征。这些 HA-E
DA 衍
生物被用来控制苯甲酰-半胱
氨酸(BC)基团的官能化程度,这些基团既能在
水介质中自组装,又能发生氧化交联。特别是,在 pH 值为 7.4 的杜氏
磷酸盐缓冲溶液(DPBS)中,通过比色法和流变学测量,研究了 HA-E
DA-BC 衍
生物中
硫醇基团的氧化动力学。通过使用两种不同浓度值(1% 和 1.5% w/v)的 HA-E
DA-BC,对氧化交联后获得的
化学水凝胶的机械性能进行了评估。这些
水凝胶显示出与软组织细胞外基质类似的致密互连纤维状结构,并具有耐
化学和酶
水解的特性。因此,我们使用原代人类软骨细胞对 HA-E
DA-BC
水凝胶作为软骨再生支架的潜在适用性进行了初步评估,并评估了它们的活力和产生细胞外基质
胶原蛋白的能力。