EAGER: Directionally Aligned Macroporous Ceramics with In-Situ Synthesized Functional Polymer Microgels as a Platform for Next Generation Membrane Chromatography

单克隆抗体是能够特异性结合靶分子或受体的蛋白质。通过这种特异性结合，抗体成为副作用减少的高活性药物。单克隆抗体等生物制药市场正在迅速增长，预计到2020年全球销售额将达到1250亿美元。对抗体和相关生物制剂的需求不断增长，推高了使用这些产品的治疗成本。因此，生物制药行业越来越受到监管机构，医疗保健提供商和消费者的压力，以降低生产和治疗成本。在生物加工过程中纯化单克隆抗体既缓慢又昂贵，占制造费用的80%以上。在下游生物制药生产中，与传统的树脂柱床相比，膜吸附器正在成为更有效的分离系统。膜吸附器可以以高得多的流速和通量操作，因此非常适合于减少处理时间和生产成本。EAGER项目的总体目标是为新一代大孔膜材料和模块奠定基础，以克服现有商业膜吸附器的容量，选择性和通量限制。为了实现这一目标，具有高蛋白结合能力和选择性的功能聚合物将与高表面积的大孔陶瓷支架相结合，这些支架可以配置成可扩展的模块，用于连续的生物加工。在生物制药制造领域，向基于单克隆抗体（mAb）的精确靶向治疗的理想过渡取决于大幅提高制造速度和降低生产成本。尽管膜色谱法已经显示出优于标准柱色谱法的优点，包括更高的通量和更低的成本，但其受到商业膜吸附剂的低蛋白结合能力和选择性以及复杂的模块配置和制造的限制。因此，迫切需要新一代的膜吸附剂材料，其可以容易地配置成具有高结合能力和选择性的可扩展模块。该项目旨在为下一代可扩展的膜吸附器材料和模块奠定基础，用于下游生物制药制造，克服现有商业膜的局限性。该EAGER项目将专注于实现两个特定目标：1）用于mAb纯化的具有高蛋白结合能力的耐盐膜吸附器的设计、制备和表征;以及2）用于选择性mAb捕获和从生物反应器收获物中回收的膜吸附器。为这些膜吸附器建立基础的策略依赖于使用定向溶液冷冻铸造设计具有可调孔径、结构和形态的大孔陶瓷家族。在多孔支架的基础上，将采取双管齐下的方法。首先，采用原位聚合和相分离微成型技术，在大孔陶瓷支架内制备功能性聚合物微凝胶，该微凝胶含有高浓度的配体，具有大的蛋白结合能力和选择性。其次，将制备高度曲折的树枝状孔的保形微凝胶涂层，以在大孔支架内提供流体动力学捕获和吸附位点。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

A monoclonal antibody is a protein capable of specifically binding a targeted molecule or receptor. Through this specific binding, antibodies become highly active drugs with reduced side effects. The market for biopharmaceuticals, such as monoclonal antibodies, is growing rapidly, with worldwide sales expected to reach $125 billion by 2020. The growing demand for antibodies and related biologics has driven up the cost of treatment using these products. As a result, the biopharmaceutical industry is increasingly under pressure from regulators, healthcare providers, and consumers to decrease production and treatment costs. Purification of monoclonal antibodies during bioprocessing is both slow and costly, representing more than 80% of the manufacturing expense. Membrane adsorbers are emerging as more efficient separation systems compared to conventional resin column beds in downstream biopharmaceutical manufacturing. Membrane adsorbers can be operated with much higher flow rates and throughput and, thus, are ideally suited for reducing processing times and production costs. The overarching goal of the EAGER project is to build the foundation for a new generation of macroporous membrane materials and modules that overcome the capacity, selectivity, and throughput limitations of existing commercial membrane adsorbers. To achieve this goal, functional polymers with high protein binding capacity and selectivity will be coupled with high surface area macroporous ceramic scaffolds, which can be configured into scalable modules for continuous bioprocessing. Within the biopharmaceutical manufacturing community, the desired transition to precisely targeted therapeutics based on monoclonal antibodies (mAb) depends on dramatically increasing manufacturing speed and reducing production costs. Although membrane chromatography has demonstrated advantages over standard column chromatography, including higher throughput and lower cost, it is limited by low protein binding capacity and selectivity of commercial membrane adsorbers as well as complex module configurations and fabrication. Consequently, there is a critical need for a new generation of membrane adsorber materials that can be readily configured into scalable modules with high binding capacity and selectivity. This project seeks to build a foundation for the next generation of scalable membrane adsorber materials and modules for downstream biopharmaceutical manufacturing that overcome the limitations of existing commercial membranes. This EAGER project will focus on achieving two specific objectives: the design, preparation, and characterization of 1) salt-tolerant membrane adsorbers with high protein binding capacity for mAb purification; and 2) membrane adsorbers for selective mAb capture and recovery from bioreactor harvests. The strategy to establish the foundation for these membrane adsorbers relies upon the design of a family of macroporous ceramics with tunable pore size, structure, and morphology using directional solution freeze casting. Building upon the porous scaffolds, a two-pronged approach will be undertaken. Firstly, in-situ polymerization and phase-separation micromolding will be employed to prepare functional polymer microgels inside macroporous ceramic scaffolds that contain high concentrations of ligands with large protein binding capacity and selectivity. Secondly, conformal microgel coatings of highly tortuous dendritic pores will be prepared to provide hydrodynamic trapping and adsorption sites inside macroporous scaffolds. Fundamental understanding of the material preparation and functionalization process and protein binding capacity and selectivity will be developed.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.