NSF/FDA SIR: Defining Print Fidelity and Performance of Bioactive 3D Printed Scaffolds.

非技术：通过3D打印可降解聚合物获得的生物医学产品是制造合成支架和植入式装置的一种很有前途的方法。未来的生物医学植入物可能会为每个患者专门设计，使产品个性化以满足患者的特定需求。个性化的3D打印生物医学产品将根据患者的具体几何特征进行设计。这种装置还将包含针对每个病人的特定治疗剂量。然而，为了实现这种结构的可靠生产，有几个科学挑战需要解决，而这个奖项能够解决其中的一些挑战。例如，当治疗剂被封装在3D打印的聚合物中时，治疗剂和聚合物之间的相互作用会影响打印性和打印结构的质量。通过该奖项开展的工作将检查可掺入聚合物的药物的类型和数量以及药物掺入对打印质量的影响。此外，这项工作将表征3D打印聚合物支架的降解和3D打印结构的治疗释放率。由于这种3D打印支架被提议用于生物环境，因此将检查3D打印结构上细胞的生长和行为，并评估任何潜在的细胞毒性。通过该奖项开展的工作将推进定制设计3D打印聚合物设备的新兴领域，并将为其他科学家和工程师提供知识体系，以推进该领域的发展。此外，该奖项还为跨学科和新兴STEM领域的研究生和本科生提供培训。技术：3D打印是一种潜在可行的方案，可以有效地制造定制的生物医学设备。3D打印医疗设备解决了几个所需的植入物特征，例如需要打印不规则的特征形状和大小，需要植入物孔隙度以及合并或封装生物活性分子的能力。越来越多的3D打印设备被包裹在生物活性小分子、肽或其他生物活性物质中。该奖项允许在最近开发的适用于3D打印生物支架的无溶剂低模量聚酯系统中研究小分子疗法的分散。这项工作将提供对弗洛里-哈金斯相互作用参数的理解，这些参数会影响小分子治疗药物在上述粘性聚酯中的分散。将检查这种封装的生物活性物质对打印保真度的影响，这项工作将为预测可以在这种3D打印支架中掺入的生物活性物质的量提供基础。研究这种生物活性支架的降解行为以及检测3D打印支架中生物活性物质的释放行为是本文工作的一个重要组成部分。最后，对支架及其降解产物的细胞毒性进行了评价。

Non-technical: Biomedical products obtained through 3D printing of degradable polymers is a promising method for the fabrication of synthetic scaffolds and implantable devices. Future biomedical implants will likely be designed specifically for each patient, personalizing the product to the specific needs of the patient. Personalized 3D printed biomedical products will be designed with patient specific geometric features. Such devices will also contain therapeutic dosages specific for each patient. However to get to the reliable production of such structures, there are several scientific challenges that need to be addressed and this award enables addressing some of these challenges. For example, when a therapeutic is encapsulated within a polymer that is 3D printed, the interactions between the therapeutic and the polymer affect the printability and the quality of the printed structure. Work carried out through this award will examine the type and amount of drugs that can be incorporated in polymers and the effects of drug incorporation on the print quality. Furthermore, the work will characterize the degradation of the 3D printed polymer scaffolds and the rate of therapeutic release from the 3D printed structures. Since such 3D printed scaffolds are proposed to be used in a biological context, the growth and behavior of cells on the 3D printed structures will be examined and any potential cytotoxicity will be evaluated. The work carried out through this award will advance the nascent field of custom designed 3D printed polymeric devices and will provide a body of knowledge for other scientists and engineers to advance the field. In addition, the award provides training for graduate and undergraduate students in an interdisciplinary and emergent STEM field.Technical: 3D printing is a potentially viable protocol for efficient manufacturing of customized biomedical devices. 3D printing medical devices addresses several desired implant features such as the need to print irregular feature shapes and sizes and the need for implant porosity and the ability to incorporate or encapsulate bioactive molecules. Increasingly, such 3D printed devices are encapsulated with bioactive small molecules, peptides or other biologically active agents. This award enables the study of dispersion of small molecule therapeutics within a recently developed solvent-free, low modulus polyester system that is suitable for 3D printing bio-scaffolds. The work will provide an understanding of the Flory-Huggins interaction parameters that affect the dispersion of small molecule therapeutics in the above described viscous polyester. The effect of such encapsulated bioactives on the print fidelity will be examined and the work will provide a foundation to predict the amount of bioactive that can be incorporated within such 3D printed scaffolds. An important part of the proposed work is to study the degradation behavior of such bioactive scaffolds and examine the release behavior of bioactives from the 3D printed scaffolds. Finally, the work will evaluate the cytotoxicity of the scaffolds and their degradation products.