Bucciarelli Alessio, Selicato Nora, Coricciati Chiara, Rainer Alberto, Capodilupo Agostina Lina, Gigli Giuseppe, Moroni Lorenzo, Polini Alessandro, Gervaso Francesca
Laboratorio RAMSES, IRCCS Istituto Ortopedico Rizzoli, Via di Barbiano 1/10, 40136 Bologna, Italy.
CNR NANOTEC - Institute of Nanotechnology, National Council of Research, University Campus Ecotekne, Via Monteroni, 73100 Lecce, Italy.
J Mater Chem B. 2024 Oct 17;12(40):10221-10240. doi: 10.1039/d4tb00670d.
Hydrogels of biopolymers are gradually substituting synthetic hydrogels in tissue engineering applications due to their properties. However, biopolymeric hydrogels are difficult to standardize because of the intrinsic variability of the material and the reversibility of physical crosslinking processes. In this work, we synthesized a photocrosslinkable derivative of chitosan (Cs), namely methacrylated chitosan (CsMA), in which the added methacrylic groups allow the formation of hydrogels through radical polymerization triggered by UV exposure. We then performed a systematic study to link the physical properties of the materials to its preparation parameters to standardize its preparation according to specific applications. We studied the properties of CsMA solutions and the derived hydrogels using a statistical method, namely, response surface method, which allowed us to build empirical models describing material properties in terms of several selected processing factors. In particular, we studied the viscosity of CsMA solutions as a function of CsMA concentration, temperature, and shear rate, while hydrogel compression modulus, morphology, degradation and solubilization were investigated as a function of CsMA concentration, photoinitiator concentration and UV exposure. CsMA solutions resulted in shear thinning and were thus suitable for extrusion-based 3D printing. The CsMA hydrogel was found to be highly tunable, with a stiffness in the 12-64 kPa range, and was stable over a long timeframe (up to 60 days). Finally, the possibility to engineer hydrogel stiffness through an empirical model allowed us to hypothesize a number of possible applications based on the mechanical properties of several biological tissues reported in the literature.
由于其特性，生物聚合物水凝胶在组织工程应用中逐渐取代了合成水凝胶。然而，由于材料的内在变异性和物理交联过程的可逆性，生物聚合物水凝胶难以标准化。在这项工作中，我们合成了壳聚糖（Cs）的光可交联衍生物，即甲基丙烯酸化壳聚糖（CsMA），其中添加的甲基丙烯酸基团允许通过紫外线照射引发的自由基聚合形成水凝胶。然后，我们进行了一项系统研究，将材料的物理性质与其制备参数联系起来，以便根据特定应用对其制备进行标准化。我们使用一种统计方法，即响应面法，研究了CsMA溶液和衍生水凝胶的性质，这使我们能够建立经验模型，根据几个选定的加工因素来描述材料性质。特别是，我们研究了CsMA溶液的粘度作为CsMA浓度、温度和剪切速率的函数，同时研究了水凝胶的压缩模量、形态、降解和溶解作为CsMA浓度、光引发剂浓度和紫外线照射的函数。CsMA溶液表现出剪切变稀特性，因此适用于基于挤出的3D打印。发现CsMA水凝胶具有高度可调性，刚度在12 - 64 kPa范围内，并且在很长一段时间内（长达60天）稳定。最后，通过经验模型设计水凝胶刚度的可能性使我们能够根据文献中报道的几种生物组织的力学性能假设一些可能的应用。
