Microproteomics, the profiling of protein expressions in small cell populations or individual cells, is essential for understanding complex biological systems. However, sample loss and insufficient sensitivity of analytical techniques pose severe challenges to this field. Microfluidics, particularly droplet-based microfluidics, provides an ideal approach by enabling miniaturized and integrated workflows to process samples and offers several advantages, including reduced sample loss, low reagent consumption, faster reaction times, and improved throughput. Droplet-based microfluidics manipulates droplets of fluids to function as discrete reaction units, enabling complex chemical reactions and biological workflows in a miniaturized setting. This article discusses a variety of on-chip functions of droplet-based microfluidics, including cell sorting, cell culture, and sample processing. We then highlight recent advances in the mass spectrometry (MS)-based analysis of single cells using droplet-based microfluidic platforms, including digital microfluidics (DMF). Finally, we review the integrated DMF–MS systems that enable automated and parallel proteomic profiling of single cells with high sensitivity and discuss the applications of the technology and its future perspectives.

中文翻译：

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基于液滴的微流体与质谱分析用于微蛋白质组学


微蛋白质组学是对小细胞群或单个细胞中蛋白质表达的分析，对于理解复杂的生物系统至关重要。然而，样品损失和分析技术灵敏度不足给该领域带来了严峻的挑战。微流体，特别是基于液滴的微流体，通过实现小型化和集成的工作流程来处理样品提供了一种理想的方法，并具有多种优点，包括减少样品损失、低试剂消耗、更快的反应时间和提高的通量。基于液滴的微流体控制流体液滴作为离散反应单元，在微型环境中实现复杂的化学反应和生物工作流程。本文讨论了基于液滴的微流体的各种片上功能，包括细胞分选、细胞培养和样品处理。然后，我们重点介绍使用基于液滴的微流体平台（包括数字微流体 (DMF)）对单细胞进行基于质谱 (MS) 分析的最新进展。最后，我们回顾了集成的 DMF-MS 系统，该系统能够以高灵敏度对单细胞进行自动化和并行蛋白质组学分析，并讨论该技术的应用及其未来前景。