Organic/Inorganic Hybrid 'Bioinks' for 3D Bioprinting

随着获得更好的医疗保健和饮食，我们的器官在生命的后期失败，如果不及时移植，就会导致死亡。因此，随着人口平均年龄的增加，等待器官移植的人数增加，但捐赠者和可用器官的数量仍然很低。目前，在英国，平均每年有超过1300人在等待名单上死亡或因病无法接受器官移植。更多的人还遭受有限或较差的植入物选择，用于修复和再生因疾病或创伤而受损的组织。为了克服这种器官短缺和可用植入物的局限性，已经探索了几种组织工程策略。一种有前途的方法是3D生物打印，这是一种逐层制造技术，用于使用活细胞、生物分子和生物材料生产可移植的器官和组织贴片。每个器官都是硬组织（骨骼）或软组织（皮肤，肺，心脏等）的复杂结构，在某种程度上，其结构和组成对每个人来说都是独一无二的。在这里，生物打印是一种很有前途的技术，可以在手术室内按下按钮，生产出与患者自身非常相似的器官和组织贴片。然而，在这成为现实之前，还存在一些关键挑战。一个主要的挑战是开发新的功能性生物材料，也称为3D生物打印的“生物墨水”。生物油墨是生物打印的重要组成部分，它们为生物货物提供结构支撑和安全环境。目前的生物墨水由软水凝胶制成，其：不能很好地保持印刷形状;在生理条件下具有差的机械性能;并且是天然来源的，因此具有固有的批次间变化。理想的生物墨水应该是完全合成的，易于打印，具有可调的机械性能，并且一旦植入就应该产生有利的宿主组织-材料相互作用。我们建议，这可以通过开发基于硅胶的有机/无机混合生物墨水通过生物友好的自下而上的过程来实现。基于低温溶液的技术可用于生产具有一系列特性的材料，从与骨形成结合的高强度生物活性玻璃到适合软骨和皮肤再生的柔软和灵活的有机/无机混合物。首先，我们将开发新的前体，并研究生物友好的加工条件来生产生物墨水。然后使用3D打印机生产类似于人体组织的组织结构。

With access to better healthcare and diet we are outliving our organs which at latter stages of life fail tragically leading to death if not transplanted on time. Therefore with increasing average age of the population, the number of people on the waiting list for an organ transplant increases, yet the amount of donors and available organs remains at a low. Currently, in the UK on average >1300 people per year either die whilst on the waiting list or became too sick to receive an organ transplant. Many more people are also suffering from limited or poor implant choices for repair and regeneration of tissue damaged from disease or trauma. To overcome this shortage of organs and the limitations of available implants several tissue engineering strategies have been explored. One promising approach is 3D bioprinting, which is a layer-by-layer fabrication technique for the production of implantation-ready organs and tissue patches using living cells, biomolecules and biomaterials. Every organ is a complex structure of either hard (bone) or soft (skin, lung, heart, etc) tissues, and to some degree its structure and composition are unique to every person. Here, bioprinting is a promising technique for the production of organs and tissue patches that are a close mimic of the patient's own, within the operating theatre at the touch of a button. However, several key challenges exist before this becomes a reality. One major challenge is the development of new functional biomaterials also called "bioinks" for 3D bioprinting. Bioinks are an important part of bioprinting, they provide structural support and a safe environment for the living cargo. Current bioinks are made of soft hydrogels which: do not maintain the printed shaped very well; have poor mechanical properties at physiological conditions; and are of natural origin hence have an inherent batch-to-batch variation. An ideal bioink should be fully synthetic and easily printable, have tuneable mechanical properties, and once implanted should produce a favourable host tissue-material interaction. We propose that this can be achieved by developing a silica-gel-based organic/inorganic hybrid bioink via a bio-friendly bottom-up process. Low temperature solution-based technique can be used to produce materials with a range of properties, from high strength bioactive glasses that form bond to bone to soft and flexible organic/inorganic hybrids that are suitable for cartilage and skin regeneration. First, we will develop novel precursors and investigate bio-friendly processing conditions to produce the bioinks. Then using a 3D printer produce tissues constructs resembling those of human tissues.