PDF(Pubmed)
Abstract：
Although visible light-based stereolithography (SLA) represents an affordable technology for the rapid prototyping of 3D scaffolds for in vitro support of cells, its potential could be limited by the lack of functional photocurable biomaterials that can be SLA-structured at micrometric resolution. Even if innovative photocomposites showing biomimetic, bioactive, or biosensing properties have been engineered by loading inorganic particles into photopolymer matrices, main examples rely on UV-assisted extrusion-based low-resolution processes. Here, SLA-printable composites were obtained by mixing a polyethylene glycol diacrylate (PEGDA) hydrogel with multibranched gold nanoparticles (NPs). NPs were engineered to copolymerize with the PEGDA matrix by implementing a functionalization protocol involving covalent grafting of allylamine molecules that have C═C pendant moieties. The formulations of gold nanocomposites were tailored to achieve high-resolution fast prototyping of composite scaffolds via visible light-based SLA. Furthermore, it was demonstrated that, after mixing with a polymer and after laser structuring, gold NPs still retained their unique plasmonic properties and could be exploited for optical detection of analytes through surface-enhanced Raman spectroscopy (SERS). As a proof of concept, SERS-sensing performances of 3D printed plasmonic scaffolds were successfully demonstrated with a Raman probe molecule (e.g., 4-mercaptobenzoic acid) from the perspective of future extensions to real-time sensing of cell-specific markers released within cultures. Finally, biocompatibility tests preliminarily demonstrated that embedded NPs also played a key role by inducing physiological cell-cytoskeleton rearrangements, further confirming the potentialities of such hybrid nanocomposites as groundbreaking materials in laser-based bioprinting.
摘要：
尽管基于可见光的立体光刻（SLA）代表了一种经济实惠的技术，用于3D支架的快速成型，用于体外支持细胞，它的潜力可能受到缺乏功能性光固化生物材料的限制，这些材料可以在微米分辨率下进行SLA结构。即使创新的光复合材料显示出仿生，生物活性，或通过将无机颗粒加载到光敏聚合物基质中来设计生物传感特性，主要示例依赖于基于UV辅助挤出的低分辨率工艺。这里,通过将聚乙二醇二丙烯酸酯（PEGDA）水凝胶与多分支金纳米颗粒（NP）混合，获得了SLA可印刷的复合材料。通过实施涉及共价接枝具有C=C侧基部分的烯丙胺分子的官能化方案,将NP工程化以与PEGDA基质共聚。调整金纳米复合材料的配方，以通过基于可见光的SLA实现复合支架的高分辨率快速成型。此外，事实证明，与聚合物混合后和激光成型后，金NP仍然保留其独特的等离子体性质，可以通过表面增强拉曼光谱（SERS）用于分析物的光学检测。作为概念的证明，使用拉曼探针分子成功证明了3D打印等离子体支架的SERS传感性能（例如，4-巯基苯甲酸）从未来扩展到实时感知培养物中释放的细胞特异性标志物的角度来看。最后,生物相容性试验初步证明，嵌入的NPs也通过诱导生理性细胞骨架重排发挥了关键作用，进一步证实了这种混合纳米复合材料作为基于激光的生物打印的突破性材料的潜力。
