Stranski-Laboratorium für Physikalische und Theoretische Chemie, Institut für Chemie, Technische Universität Berlin, Straße des 17. Juni 124, Sekr. TC 7, 10623 Berlin, Germany.
Institut für Chemie und Biochemie, Takusstraße 3, Freie Universität Berlin, 14195 Berlin, Germany; Tissue Engineering Laboratory & Berlin-Brandenburg School for Regenerative Therapies, Department of Rheumatology, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117 Berlin, Germany.
Colloids Surf B Biointerfaces. 2017 Nov 1;159:477-483. doi: 10.1016/j.colsurfb.2017.07.073. Epub 2017 Aug 5.
Osteoarthritis (OA) is a disabling condition especially in the elderly population. The current therapeutic approaches do not halt the OA progression or reverse joint damage. In order to overcome the problem of rapid clearance of hyaluronic acid (HA), a standard viscosupplement for OA, we investigated the rheological properties of a relatively non-degradable dendritic polyglycerol sulfate (dPGS) hydrogel to determine a suitable concentration for intra articular injections that mimics HA in terms of its viscoelastic and mechanical properties. To do so, the concentration range from 3.6 to 4.8wt% of dPGS and, as a reference, blends of commercially available HAs (Ostenil, GO-ON, Synocrom Forte and Synvisc), were investigated by means of oscillating and flow rheology, thereby yielding storage (G') and loss modulus (G"), as well as yield stress and shear viscosity. In our rheological experiments we observe a pronounced coupling of the molecular weight and the rheological properties for the HAs. Furthermore, we find the dPGS hydrogel to form more compact networks with increasing concentration. From a broader comparison the current findings suggest that an overall polymer concentration of 4.0wt% dPGS has viscoelastic properties that are comparable to hyaluronic acid in the medically relevant frequency range, where for medical application the dPGS hydrogel has the advantage of being much less easily displaced from its injection place than HA.
骨关节炎（OA）是一种致残性疾病，尤其是在老年人群中。目前的治疗方法无法阻止 OA 的进展或逆转关节损伤。为了克服透明质酸（HA）快速清除的问题，HA 是 OA 的标准粘性补充剂，我们研究了相对不可降解的树枝状聚甘油硫酸酯（dPGS）水凝胶的流变性能，以确定适合关节内注射的浓度，使其在粘弹性和机械性能方面模拟 HA。为此，研究了浓度范围为 3.6 至 4.8wt%的 dPGS，以及作为参考的市售 HA（Ostenil、GO-ON、Synocrom Forte 和 Synvisc）混合物，通过振荡和流动流变学进行了研究，从而得出储能模量（G'）和损耗模量（G"），以及屈服应力和剪切粘度。在我们的流变实验中，我们观察到 HA 的分子量和流变性能之间存在明显的耦合。此外，我们发现 dPGS 水凝胶随着浓度的增加形成更紧凑的网络。从更广泛的比较来看，目前的研究结果表明，聚合物浓度为 4.0wt%的 dPGS 具有粘弹性，在医学相关的频率范围内与透明质酸相当，而对于医学应用，dPGS 水凝胶具有不易从注射部位移位的优势比 HA 更明显。
