Multi-material stereolithographic 3D-printing for prototyping Tissue Chips

项目摘要/摘要 组织芯片-含有3D结构中的人体细胞的微流控设备，试图重述 人体组织和器官的生理学和病理生理学-包含严格要求 3D/模块化制造、多种材料和功能的整合以及流体自动化。 绝大多数组织芯片仍是聚二甲基硅氧烷(PDMS)的原型。然而，困难的是 PDMS作为组织芯片材料仍然存在障碍。PDMS的表面是多孔的和疏水的，所以两者 吸附到PDMS和吸附在PDMS上可能会改变实验结果 目标浓度和通过在微流控设备的不需要的区域中分配分子。 3D-Print在纸巾芯片方面有着明显的潜力。特别是立体平版印刷(SL)一直是一种 在高分辨率下调制3D形状的绝佳选择，但调制材料成分仍然是一种 挑战。迫切需要更先进、高分辨率和多材料的SL打印 构建能够集成设备(通道)的结构组件的未来组织芯片的方法 生物制造(细胞和支架)。然而，SL打印多材料还没有现成的解决方案 具有广泛适用性的微流控装置。 本申请提出了环甲基丙烯酸辛酯(COMA)树脂的合成及SL印花， 将能够将任何选择的生物分子叠氮固定在COMA打印的表面上。 用于通过直接的无铜(生物兼容)点击化学来衍生打印部件的Coma，在这种情况下 通过偶联到叠氮基团，该叠氮基在水中自发地和昏迷基团特异地反应 解决办法。使用生物素叠氮化物(市售)和亲和素连接，我们将能够固定任何 生物素化的生物分子被选在Coma打印的表面上。我们还将使用基准丙烯酸酯树脂 由聚乙二醇二丙烯酸酯(MW~258)(PEG-DA-258)组成，已成功应用于 由几个实验室开发的微流体，并将试验将聚乙二醇DA-258与其他双丙烯酸酯和/或 单丙烯酸酯，以获得具有不同性质的树脂，如更高的柔韧性。打印制造的设备 部分使用PEGDA-258树脂(或混合)，部分使用COMA树脂(或混合)，我们将利用一种策略 用于共同打印Folch实验室最近使用的多种丙烯酸酯树脂，包括暂停打印和 换大桶里的树脂。该方案将对3D打印微流控器件具有广泛的适用性 具有分子功能的多个区域(例如，生物分子检测、细胞捕获)和/或具有 独特的传感/执行特性(例如微型阀、力传感器等)。示例包括3D打印 基于昏迷衍生区域的复合免疫传感器，用于药物筛选的细胞捕获设备，以及 芯片上的有机化合物自动化平台等。

PROJECT SUMMARY / ABSTRACT Tissue Chips – microfluidic devices containing human cells in 3D architectures that attempt to recapitulate the physiology and pathophysiology of human tissues and organs – contain advanced designs that critically require 3D/modular fabrication, the incorporation of multiple materials and functionalities, and fluidic automation. The vast majority of Tissue Chips are still prototyped in poly(dimethylsiloxane) (PDMS). However, difficult barriers remain for PDMS as a Tissue Chip material. The surface of PDMS is porous and hydrophobic, so both absorption into PDMS and adsorption onto PDMS can potentially alter experimental outcomes by changing the target concentrations and by partitioning molecules in undesired regions of a microfluidic device. 3D-Printing holds an obvious potential for Tissue Chips. Stereolithography (SL), in particular, has been an excellent choice for modulating shapes in 3D at high resolution but modulating material composition is still a challenge. There is a critical need for more advanced, high-resolution and multi-material SL-printing approaches to building future Tissue Chips that can integrate the structural components of a device (channels and valves) with biofabrication (cells and scaffolds). Yet there is no off-the-shelf solution to SL-print multi-material microfluidic devices of wide applicability. This application proposes the synthesis and SL-printing of cyclo-octyne methacrylate (COMA) resin, which will enable the immobilization of any biomolecule-azide of choice onto the COMA-printed surfaces. COMA for derivatizing printed parts via straightforward copper-free (biocompatible) click chemistry, in this case by conjugation to an azide group which spontaneously and specifically reacts with the COMA group in aqueous solutions. Using biotin-azide (commercially available) and an avidin linkage, we will be able to immobilize any biotinylated biomolecule of choice onto the COMA-printed surfaces. We will also use a baseline acrylate resin composed of poly(ethylene glycol) diacrylate (MW~258) (PEG-DA-258), which has successfully been used in microfluidics by several labs, and will experiment with blending PEG-DA-258 with other diacrylates and/or monoacrylates to obtain resins with differing properties, such as higher flexibility. To print devices that are made partially with PEG-DA-258 resin (or blends) and partially with COMA resin (or blends), we will utilize a strategy for co-printing multiple acrylate resins recently utilized by the Folch lab that consists of pausing the print and exchanging the resins in the vat. This scheme will have wide applicability to 3D-print microfluidic devices with multiple regions bearing molecular functionalities (e.g. biomolecular detection, cell capture) and/or elements with distinct sensing/actuating properties (e.g. microvalves, force sensors, etc.). Examples include 3D-printed multiplexed immunosensors based on COMA-derivatized regions, cell trapping devices for drug screening, and organoid-on-a-chip automated platforms, among others.