Biomedical Engineering Department, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
Biomedical Engineering Department, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran.
Colloids Surf B Biointerfaces. 2020 Dec;196:111347. doi: 10.1016/j.colsurfb.2020.111347. Epub 2020 Sep 10.
Injectable hydrogels with conductivity are highly desirable as scaffolds for the engineering of various electrical stimuli-responsive tissues, including nerve, muscle, retina, and bone. However, oxygen deprivation within scaffolds can lead to failure by causing cell necrosis. Therefore, an oxygen release conductive injectable hydrogel can serve as a promising support for the regeneration of such tissues. In the present study, HO-loaded polylactic acid microparticles were fabricated. Then, gelatin-graft-polypyrrole with various pyrrole contents and periodate-oxidized pectin were synthesized, and consequently, injectable conductive hydrogel/microparticle scaffolds, inside which catalase was grafted and trapped, were obtained. The results revealed that spherical particles with a mean diameter of 60.39 μm and encapsulation efficiency of 49.64 %, which persistently provided oxygen up to 14 days, were achieved. Investigations on hydrogels revealed that with the increase of pyrrole content of gelatin-graft-polypyrrole from 0 to 15 %, the swelling ratio, pore size, porosity, and conductivity were increased from 6.5 to 11.8, 173.13 μm-295.96 μm, 79.7%-93.8%, and from 0.06 mS/m to 2.14 mS/m, respectively. On the other hand, the crosslinking degree and compressive modulus of hydrogels were shown to decrease from 67.24%-27.35%, and from 214.1 kPa to 64.4 kPa, respectively. Moreover, all formulations supported cell viability and attachment. Overall, the hydrogel/particle scaffold with the merits of electrical conductivity, injectability, compatibility, and sustained oxygen release can be used as a tissue engineering scaffold, promoting the regeneration of electricity responsive tissues. Considering all the aforementioned characteristics and behavior of the fabricated scaffolds, they may be promising candidates for bone tissue engineering applications.
具有导电性的可注射水凝胶作为各种电刺激响应组织（包括神经、肌肉、视网膜和骨骼）工程的支架是非常理想的。然而，支架内的缺氧会导致细胞坏死，从而导致支架失效。因此，一种能够释放氧气的导电可注射水凝胶可以作为此类组织再生的有前途的支撑物。在本研究中，制备了负载 HO 的聚乳酸微球。然后，合成了具有不同吡咯含量和高碘酸盐氧化果胶的明胶接枝聚吡咯，随后获得了接枝和捕获了过氧化氢酶的可注射导电水凝胶/微球支架。结果表明，成功制备了平均直径为 60.39 μm、包封效率为 49.64%的球形颗粒，其可持续提供氧气长达 14 天。对水凝胶的研究表明，随着明胶接枝聚吡咯中吡咯含量从 0 增加到 15%，水凝胶的溶胀比、孔径、孔隙率和电导率分别从 6.5 增加到 11.8、173.13 μm-295.96 μm、79.7%-93.8%和从 0.06 mS/m 增加到 2.14 mS/m。另一方面，水凝胶的交联度和压缩模量分别从 67.24%-27.35%和 214.1 kPa 降低至 64.4 kPa。此外，所有配方均支持细胞活力和附着。总的来说，具有导电性、可注射性、相容性和持续氧气释放优点的水凝胶/颗粒支架可用作组织工程支架，促进对电刺激有响应的组织的再生。考虑到所制备支架的所有上述特性和行为，它们可能是骨组织工程应用的有前途的候选物。
