Camp Christopher P, Peterson Ingrid L, Knoff David S, Melcher Lauren G, Maxwell Connor J, Cohen Audrey T, Wertheimer Anne M, Kim Minkyu
Department of Biomedical Engineering, University of Arizona, Tucson, AZ, United States.
Applied Biosciences GIDP, University of Arizona, Tucson, AZ, United States.
Front Chem. 2020 Mar 13;8:173. doi: 10.3389/fchem.2020.00173. eCollection 2020.
Controlling mechanical properties of polymeric biomaterials, including the elastic modulus, is critical to direct cell behavior, such as proliferation and differentiation. Dityrosine photocrosslinking is an attractive and simple method to prepare materials that exhibit a wide range of elastic moduli by rapidly crosslinking tyrosyl-containing polymers. However, high concentrations of commonly used oxidative crosslinking reagents, such as ruthenium-based photoinitiators and persulfates, present cytotoxicity concerns. We found the elastic moduli of materials prepared by crosslinking an artificial protein with tightly controlled tyrosine molarity can be modulated up to 40 kPa by adjusting photoinitiator and persulfate concentrations. Formulations with various concentrations of the crosslinking reagents were able to target a similar material elastic modulus, but excess unreacted persulfate resulted in cytotoxic materials. Therefore, we identified a systematic method to prepare non-cytotoxic photocrosslinked polymeric materials with targeted elastic moduli for potential biomaterials applications in diverse fields, including tissue engineering and 3D bioprinting.
控制包括弹性模量在内的聚合物生物材料的力学性能对于引导细胞行为（如增殖和分化）至关重要。二酪氨酸光交联是一种有吸引力且简单的方法，通过快速交联含酪氨酸的聚合物来制备具有广泛弹性模量的材料。然而，高浓度的常用氧化交联剂，如钌基光引发剂和过硫酸盐，存在细胞毒性问题。我们发现，通过调节光引发剂和过硫酸盐的浓度，交联具有严格控制酪氨酸摩尔浓度的人工蛋白质所制备的材料的弹性模量可调节至40kPa。含有不同浓度交联剂的配方能够靶向相似的材料弹性模量，但过量未反应的过硫酸盐会导致材料具有细胞毒性。因此，我们确定了一种系统方法，用于制备具有靶向弹性模量的无细胞毒性光交联聚合物材料，以用于包括组织工程和3D生物打印在内的不同领域的潜在生物材料应用。
