Center for Biomedical Engineering, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Cambridge, MA 02139, USA; Harvard-MIT Division of Health Sciences and Technology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, MA 02115, USA; David H. Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Biomaterials. 2013 May;34(16):3970-3983. doi: 10.1016/j.biomaterials.2013.01.045. Epub 2013 Mar 1.
Poly(glycerol sebacate) (PGS), a tough elastomer, has been proposed for tissue engineering applications due to its desired mechanical properties, biocompatibility and controlled degradation. Despite interesting physical and chemical properties, PGS shows limited water uptake capacity (∼2%), thus constraining its utility for soft tissue engineering. Therefore, a modification of PGS that would mimic the water uptake and water retention characteristics of natural extracellular matrix is beneficial for enhancing its utility for biomedical applications. Here, we report the synthesis and characterization of highly elastomeric poly(glycerol sebacate)-co-polyethylene glycol (PGS-co-PEG) block copolymers with controlled water uptake characteristics. By tailoring the water uptake property, it is possible to engineer scaffolds with customized degradation and mechanical properties. The addition of PEG results in almost 15-fold increase in water uptake capacity of PGS, and improves its mechanical stability under dynamic loading conditions. PGS-co-PEG polymers show elastomeric properties and can be subjected to serve deformation such as bending and stretching. The Young's modulus of PGS-co-PEG can be tuned from 13 kPa to 2.2 MPa by altering the amount of PEG within the copolymer network. Compared to PGS, more than six-fold increase in elongation was observed upon PEG incorporation. In addition, the rate of degradation increases with an increase in PEG concentration, indicating that degradation rate of PGS can be regulated. PGS-co-PEG polymers also support cell proliferation, and thus can be used for a range of tissue engineering applications.
聚（癸二酸甘油酯）（PGS）是一种坚韧的弹性体，由于其理想的机械性能、生物相容性和可控降解性，已被提议用于组织工程应用。尽管具有有趣的物理和化学性质，但 PGS 的吸水率有限（约 2%），因此限制了其在软组织工程中的应用。因此，对 PGS 进行改性，使其模仿天然细胞外基质的吸水率和保水特性，有利于提高其在生物医学应用中的效用。在这里，我们报告了具有可控吸水率特性的高弹性聚（癸二酸甘油酯）-共-聚乙二醇（PGS-co-PEG）嵌段共聚物的合成和表征。通过调整吸水率，可以设计具有定制降解和机械性能的支架。PEG 的添加使 PGS 的吸水率增加了近 15 倍，并提高了其在动态加载条件下的机械稳定性。PGS-co-PEG 聚合物具有弹性体性质，可以承受弯曲和拉伸等变形。通过改变共聚物网络中 PEG 的量，可以将 PGS-co-PEG 的杨氏模量从 13 kPa 调至 2.2 MPa。与 PGS 相比，PEG 掺入后伸长率增加了六倍以上。此外，随着 PEG 浓度的增加，降解速率增加，表明可以调节 PGS 的降解速率。PGS-co-PEG 聚合物还支持细胞增殖，因此可用于多种组织工程应用。
