当前位置：
X-MOL 学术
›
Biomater. Sci.
›
论文详情
Our official English website, www.x-mol.net, welcomes your
feedback! (Note: you will need to create a separate account there.)
Effect of ionic strength on shear-thinning nanoclay–polymer composite hydrogels†
Biomaterials Science ( IF 5.8 ) Pub Date : 2018-06-06 00:00:00 , DOI: 10.1039/c8bm00469b Amir Sheikhi 1 , Samson Afewerki , Rahmi Oklu , Akhilesh K Gaharwar , Ali Khademhosseini
Biomaterials Science ( IF 5.8 ) Pub Date : 2018-06-06 00:00:00 , DOI: 10.1039/c8bm00469b Amir Sheikhi 1 , Samson Afewerki , Rahmi Oklu , Akhilesh K Gaharwar , Ali Khademhosseini
Affiliation
|
Nanoclay–polymer shear-thinning composites are designed for a broad range of biomedical applications, including tissue engineering, drug delivery, and additive biomanufacturing. Despite the advances in clay–polymer injectable nanocomposites, colloidal properties of layered silicates are not fully considered in evaluating the in vitro performance of shear-thinning biomaterials (STBs). Here, as a model system, we investigate the effect of ions on the rheological properties and injectability of nanoclay–gelatin hydrogels to understand their behavior when prepared in physiological media. In particular, we study the effect of sodium chloride (NaCl) and calcium chloride (CaCl2), common salts in phosphate buffered saline (PBS) and cell culture media (e.g., Dulbecco's Modified Eagle's Medium, DMEM), on the structural organization of nanoclay (LAPONITE® XLG-XR, a hydrous lithium magnesium sodium silicate)-polymer composites, responsible for the shear-thinning properties and injectability of STBs. We show that the formation of nanoclay–polymer aggregates due to the ion-induced shrinkage of the diffuse double layer and eventually the liquid–solid phase separation decrease the resistance of STB against elastic deformation, decreasing the yield stress. Accordingly, the stress corresponding to the onset of structural breakdown (yield zone) is regulated by the ion type and concentration. These results are independent of the STB composition and can directly be translated into the physiological conditions. The exfoliated nanoclay undergoes visually undetectable aggregation upon mixing with gelatin in physiological media, resulting in heterogeneous hydrogels that phase separate under stress. This work provides fundamental insights into nanoclay–polymer interactions in physiological environments, paving the way for designing clay-based injectable biomaterials.
中文翻译：
离子强度对剪切稀化纳米粘土-聚合物复合水凝胶的影响†
纳米粘土-聚合物剪切稀化复合材料设计用于广泛的生物医学应用，包括组织工程、药物输送和添加剂生物制造。尽管粘土聚合物可注射纳米复合材料取得了进展，但在评估剪切稀化生物材料（STB）的体外性能时，并未充分考虑层状硅酸盐的胶体特性。在这里，作为模型系统，我们研究了离子对纳米粘土明胶水凝胶的流变特性和可注射性的影响，以了解它们在生理介质中制备时的行为。特别是，我们研究了氯化钠 (NaCl) 和氯化钙 (CaCl 2 )、磷酸盐缓冲盐水 (PBS) 中的常见盐和细胞培养基（例如，Dulbecco's Modified Eagle's Medium，DMEM）对细胞结构组织的影响。纳米粘土（LAPONITE® XLG-XR，一种水合硅酸锂镁钠）-聚合物复合材料，负责 STB 的剪切稀化特性和可注射性。我们发现，由于离子诱导的扩散双层收缩以及最终的液固相分离而形成纳米粘土-聚合物聚集体，从而降低了 STB 对弹性变形的抵抗力，从而降低了屈服应力。因此，与结构破坏（屈服区）开始相对应的应力由离子类型和浓度调节。这些结果与 STB 成分无关，可以直接转化为生理条件。剥离的纳米粘土在生理介质中与明胶混合后会发生肉眼无法察觉的聚集，从而产生在压力下相分离的异质水凝胶。这项工作提供了对生理环境中纳米粘土-聚合物相互作用的基本见解，为设计基于粘土的可注射生物材料铺平了道路。
更新日期：2018-06-06
中文翻译：
离子强度对剪切稀化纳米粘土-聚合物复合水凝胶的影响†
纳米粘土-聚合物剪切稀化复合材料设计用于广泛的生物医学应用，包括组织工程、药物输送和添加剂生物制造。尽管粘土聚合物可注射纳米复合材料取得了进展，但在评估剪切稀化生物材料（STB）的体外性能时，并未充分考虑层状硅酸盐的胶体特性。在这里，作为模型系统，我们研究了离子对纳米粘土明胶水凝胶的流变特性和可注射性的影响，以了解它们在生理介质中制备时的行为。特别是，我们研究了氯化钠 (NaCl) 和氯化钙 (CaCl 2 )、磷酸盐缓冲盐水 (PBS) 中的常见盐和细胞培养基（例如，Dulbecco's Modified Eagle's Medium，DMEM）对细胞结构组织的影响。纳米粘土（LAPONITE® XLG-XR，一种水合硅酸锂镁钠）-聚合物复合材料，负责 STB 的剪切稀化特性和可注射性。我们发现，由于离子诱导的扩散双层收缩以及最终的液固相分离而形成纳米粘土-聚合物聚集体，从而降低了 STB 对弹性变形的抵抗力，从而降低了屈服应力。因此，与结构破坏（屈服区）开始相对应的应力由离子类型和浓度调节。这些结果与 STB 成分无关，可以直接转化为生理条件。剥离的纳米粘土在生理介质中与明胶混合后会发生肉眼无法察觉的聚集，从而产生在压力下相分离的异质水凝胶。这项工作提供了对生理环境中纳米粘土-聚合物相互作用的基本见解，为设计基于粘土的可注射生物材料铺平了道路。
京公网安备 11010802027423号