Department of Chemistry, University of Waterloo, 200 University Ave West, Waterloo, Ontario N2L 3G1, Canada.
Centre for Eye and Vision Research Limited, 17W, Hong Kong Science Park, Hong Kong.
ACS Appl Bio Mater. 2024 Sep 16;7(9):6286-6296. doi: 10.1021/acsabm.4c00901. Epub 2024 Sep 3.
While silicone elastomers have found widespread use in the biomedical industry, 3D printing them has proven to be difficult due to the material's slow drying time, low viscosity, and hydrophobicity. Herein, we arrested the hydrophilic silicone (HS) macrochains into a semi-interpenetrating polymer network (semi-IPN) via an photogelation-assisted 3D microextrusion printing technique. The flow behavior of the pregel solutions and the mechanical properties of the printed HS hydrogels were tested, showing a high elastic modulus (approximately 15 kPa), a low tan δ, high elasticity, and delayed network rupturing. The uniaxial compression tests demonstrated a nearly negligible permanent deformation, suggesting that the printed hybrid hydrogel maintained its elastic properties. Drug loading and diffusion in the microporous hydrogel are shown via the non-Fickian anomalous transport mechanism, leading to highly tunable loading/releasing profiles (approximately 20% cumulative release) depending on the HS concentration. The drug encapsulation exhibits exceptional stability, remaining intact without any degradation even after a storage period of 1 month. As far as we know, this is the first soft biomaterial based on HS that functions as an exceptional controlled drug delivery device.
尽管硅橡胶在生物医学领域得到了广泛的应用，但由于其干燥时间慢、粘度低和疏水性，将其 3D 打印证明是困难的。在此，我们通过光凝胶辅助 3D 微挤出打印技术将亲水性硅橡胶（HS）大分子链固定在半互穿聚合物网络（semi-IPN）中。测试了预凝胶溶液的流动行为和打印 HS 水凝胶的机械性能，表现出高弹性模量（约 15 kPa）、低 tan δ、高弹性和延迟网络破裂。单轴压缩测试表明几乎没有不可恢复的永久变形，表明打印的混合水凝胶保持其弹性性能。微孔水凝胶中的药物加载和扩散通过非菲克扩散异常传输机制进行，根据 HS 浓度可实现高度可调的加载/释放曲线（约 20%的累积释放）。药物包封表现出极好的稳定性，即使在储存 1 个月后也没有任何降解，保持完整。据我们所知，这是第一个基于 HS 的用作特殊药物控释装置的软生物材料。
