School of Traditional Chinese Pharmacy, Jiangning Hospital of Chinese Medicine, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, PR China.
School of Traditional Chinese Pharmacy, Jiangning Hospital of Chinese Medicine, State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing 211198, PR China.
Carbohydr Polym. 2024 Dec 15;346:122658. doi: 10.1016/j.carbpol.2024.122658. Epub 2024 Aug 26.
Licorice is not only a widely used food, but also a classic tonic Chinese medicine, which mainly contains glycyrrhiza polysaccharides (GP) and flavonoids with excellent anti-inflammatory and antioxidant pharmacological activities. In this study, a neutral homogeneous polysaccharide (GP1-2) was isolated from Glycyrrhiza uralensis Fisch. However, its gelation behavior and properties have yet to be comprehensively studied. In this study, a Ca cross-linked physical hydrogel based on neutral GP1-2 (GP1-2-Ca) is fabricated. The ability of metal ions to cross-linked gelation with GP1-2 is explored with respect to the polysaccharide concentrations, ion species, and pH environments. The pH range of Ca cross-linked with GP1-2 to form hydrogel is 8 to 10, and the gelation concentration ranges from 20.0 % to 50.0 % w/v. Subsequently, the properties of the GP1-2-Ca hydrogels are investigated using rheological measurements, scanning electron microscopy, free radical scavenging, MTT assays, healing capability, and enzyme-linked immunosorbent assays. The results reveal that the structure of GP1-2 presents an irregular porous structure, however, the physical gel formed after cross-linking with Ca microscopically showed a globular porous structure with uniform distribution, suggesting that this structure characteristic may be used as a carrier material for drug delivery. Meanwhile, the GP1-2-Ca hydrogel also possessed extraordinary viscoelasticity, cytocompatibility, antioxidant properties, anti-inflammatory activity, and ability to promote wound healing. Furthermore, the potential of GP1-2-Ca hydrogels as drug delivery materials was validated by using rhein as a model drug for encapsulation, it is demonstrated that its cumulative release behavior of GP1-2-Ca is pH-dependent. All in all, this study reveals the potential application of natural polysaccharides in drug delivery, highlighting its dual roles as carrier materials and bioactive ingredients.
甘草不仅是一种广泛使用的食品，还是一种经典的滋补中药，主要含有甘草多糖（GP）和黄酮类化合物，具有出色的抗炎和抗氧化药理活性。本研究从甘草中分离出一种中性均一多糖（GP1-2）。然而，其胶凝行为和性质尚未得到全面研究。本研究基于中性 GP1-2 构建了一种 Ca 交联的物理水凝胶（GP1-2-Ca）。探讨了多糖浓度、离子种类和 pH 环境对 GP1-2 与金属离子形成凝胶的能力。Ca 交联 GP1-2 形成水凝胶的 pH 范围为 8 至 10，凝胶浓度范围为 20.0%至 50.0%w/v。随后，使用流变学测量、扫描电子显微镜、自由基清除、MTT 测定、愈合能力和酶联免疫吸附测定研究了 GP1-2-Ca 水凝胶的性质。结果表明，GP1-2 的结构呈现不规则多孔结构，然而，与 Ca 交联后形成的物理凝胶微观上表现出均匀分布的球形多孔结构，表明这种结构特征可作为药物传递载体材料。同时，GP1-2-Ca 水凝胶还具有非凡的粘弹性、细胞相容性、抗氧化特性、抗炎活性和促进伤口愈合的能力。此外，通过将大黄素作为模型药物进行包封，验证了 GP1-2-Ca 水凝胶作为药物传递材料的潜力，表明其 GP1-2-Ca 的累积释放行为具有 pH 依赖性。总之，本研究揭示了天然多糖在药物传递中的潜在应用，突出了其作为载体材料和生物活性成分的双重作用。
