Nanofluidic Tools for Proteomic Sample Preparation

对生物分子样品（如血清或细胞提取物）进行详细的蛋白质组学分析可以提供有关人体健康或所研究的生物细胞的有价值的信息。然而，目前的样品制备技术无法有效处理这些生物分子样品的多样性和动态范围，因此对富含信息的少数蛋白物种（信号分子和细胞因子）的检测受到严重限制。微流体系统中高效的蛋白质分离可以为这一挑战提供解决方案，但样品体积的限制以及缺乏分子信号放大策略一直是主要问题。纳米流体的最新进展为蛋白质组学样品制备提供了有用的工具，以解决这些挑战。纳米流体过滤器可用于基于大小的蛋白质的无凝胶分离。利用纳米流控通道产生的许可选择离子电流从稀释溶液中浓缩蛋白质和多肽，增加微流控样品制备系统的样品体积容量。此外，还演示了基于连续流pi的生物分子分选系统。在本项目中，我们将进一步开发这些纳米流体组件，并将其整合到一个自动蛋白质组学样品制备系统中，该系统可以根据目标分子的性质对复杂的生物分子样品进行分类。本课题开发的微纳流体样品制备装置的灵活性和鲁棒性将极大地促进系统集成。由此产生的样品制备微装置可以很容易地与各种类型的检测器集成，包括基于抗体的生物传感器或质谱。这样的整合将使生物检测的选择性和灵敏度提高几个数量级，从而影响人类健康监测、生物标志物检测和系统生物学等各个领域。

Detailed proteomic analysis of biomolecule samples such as serum or cell extract could provide valuable information regarding the person's health or biological cells under study. However, current sample preparation technologies cannot deal with the diversity and dynamic range of these biomolecule samples effectively, and therefore the detection of information-rich minority protein species (signaling molecules and cytokines) is severely limited. Efficient protein separation in microfluidic systems could provide a solution for this challenge, but the limitation in sample volume, as well as the lack of molecular signal amplification strategy, has been major issues. Recent advances in nanofluidics provide useful tools for proteomic sample preparation, to address these challenges. Nanofluidic filters could be used for a gel-free separation of proteins based on the size. Permselective ion current generated by the nanofluidic channel was used to concentrate proteins and peptides from a dilute solution, to increase the sample volume capacity of the microfluidic sample preparation system. Also, continuous-flow pI-based biomolecule sorting system was demonstrated. In this project, we will develop these nanofluidic components further, and integrate them into an automatic proteomic sample preparation system that could sort out complex biomolecule sample based on the property of the target molecule. The flexibility and robustness of the micro/nanofluidic sample preparation devices that will be developed from this project will facilitate the system integration greatly. The resulting sample preparation microdevices could be easily integrated with various types of detectors, including antibody-based biosensor or mass spectrometry. Such an integration will enhance the selectivity and sensitivity of the biodetection by orders of magnitudes, therefore impacting various fields such as human health monitoring, biomarker detection, and systems biology.