Development of a droplet based microfluidic system for protein separation and fractionation

毛细管电泳（CE）系统是生命科学行业的重要工具，特别是用于蛋白质分析。Advanced Electrophoresis Solutions（AES）是CE工具的新兴领先开发商，其旗舰产品CEInfinite使用成像检测毛细管等电聚焦（iCIEF）技术为蛋白质分离和定量提供可靠、高性能和高通量检测。然而，该公司在满足不断增长的客户需求方面面临着严峻的挑战，并且需要：i）由于缓慢的手动胶合过程，检测盒生产率低;以及ii）由于使用单相压力驱动流（蛋白质样品与缓冲溶液混合）进行样品移动，导致样品条带扭曲和蛋白质组分稀释，回收的目标组分纯度低且体积小。 在接下来的三年里，滑铁卢大学的研究人员将与AES合作，开发解决上述问题的创新技术，并为AES在单细胞分析（SCA）领域的未来发展奠定基础，该领域具有巨大的潜力，可以发现在散装溶液环境中看不到的生物机制。具体而言，我们将：i）开发两相液滴方法，使样品注射具有灵活控制的体积; ii）开发内置膜和无膜策略，用于从iCIEF应用中所需的蛋白质样品混合物中分离电解质，以及iii）开发两相液滴方法，用于以最小稀释度（高纯度）和大体积连续回收单个蛋白质级分。所提出的创新将消除对胶合工艺的需求，从而显著提高药筒产量，并解决目标回收馏分的低体积和低纯度的挑战。关于单个液滴的主动控制的知识将为AES在SCA中追求未来的发展奠定基础，因为皮科至纳升的液滴是分离单细胞的理想选择。该项目的最终目标是帮助AES大力渗透到制药行业，并将其市场扩展到生命科学领域，重点是为SCA开发创新和仪器。

Capillary electrophoresis (CE) systems are important tools for the life sciences industry, particularly for protein analysis. Advanced Electrophoresis Solutions (AES) is an emerging leading developer of CE tools, and its flagship product, CEInfinite, provides reliable, high performance, and high throughput detection for protein separation and quantification using imaging detection capillary isoelectric focusing (iCIEF) technology. However, the company is facing critical challenges to meeting growing customer demand, and needs: i) low cartridge production rates due to slow, manual gluing processes; and ii) low purity and low volume of the recovered fraction of interest due to the use of single phase pressure driven flow (protein samples are mixed with buffer solution) for sample mobilization resulting in distorted sample bands and diluted protein fraction. Over the next three years, University of Waterloo researchers will work with AES to develop innovations that address the above issues as well as lay a foundation for AES to pursue future development in the field of single cell analysis (SCA), which holds tremendous potential for discovering biological mechanisms not seen in bulk solution settings. Specifically, we will: i) develop a two-phase droplet method, enabling sample injection with flexibly controlled volume; ii) develop a built-in membrane and a membrane-free strategy for the separation of electrolytes from protein sample mixtures required in iCIEF applications, and iii) develop a two-phase droplet method for continuous recovery of individual protein fractions with minimal dilution (high purity) and large volume. The proposed innovations will eliminate the need of gluing processes dramatically increasing cartridge production, and address the challenge of low volume and low purity of the recovered fraction of interest. The knowledge learned about active control of individual droplets will lay a foundation for AES to pursue future development in SCA as pico- to nano-liter droplets are ideal for isolation of single cells. The ultimate goal of this project is to help AES strongly penetrate into the pharmaceutical industry and also significantly expand its market into life science with emphasis on developing innovations and instruments for SCA.