Nanofluidic Tools for Proteomic Sample Preparation

对血清或细胞提取物等生物分子样本进行详细的蛋白质组学分析，可以提供有关研究对象的健康或生物细胞的有价值的信息。然而，目前的样品制备技术不能有效地处理这些生物分子样品的多样性和动态范围，从而严重限制了对信息丰富的少数蛋白质物种(信号分子和细胞因子)的检测。微流控系统中有效的蛋白质分离可以为这一挑战提供解决方案，但样品容量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样品的制备提供了有用的工具，以应对这些挑战。纳米流体过滤器可以用于基于大小的蛋白质的无胶分离。利用纳米流体通道产生的渗透选择离子电流从稀溶液中浓缩蛋白质和多肽，以增加微流控样品制备系统的样品容量。并对基于连续流PI的生物分子分选系统进行了演示。在本项目中，我们将进一步开发这些纳米流体成分，并将它们集成到一个自动蛋白质组样本制备系统中，该系统可以根据目标分子的性质筛选出复杂的生物分子样本。由该项目开发的微/纳米流体样品制备设备的灵活性和健壮性将极大地促进系统集成。由此产生的样品制备微设备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仪。这种集成将以数量级提高生物检测的选择性和灵敏度，从而影响到人类健康监测、生物标记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.