外加场分离技术与微流控技术联用在微纳尺度物质分离中的研究进展

微纳尺度物质的分离和分选在精准医学、材料科学和单细胞分析等研究中至关重要。精准、高效和快速的分离微纳尺度物质能够为癌症的早期诊断、生物样品检测和细胞筛选提供重要帮助,其中基于外加场分离技术的分离微纳尺度物质因可以对微纳尺度物质高效在线分离和分选,被广泛应用于微纳米颗粒、外泌体以及生物细胞的分离工作中,而目前多数外加场分离技术存在装备繁琐和样品消耗大等问题。微流控技术是一种通过制作微通道和微流控芯片操纵微小流体对微纳尺度样品组分进行分离的技术,因具有快速检测、高通量、在线分离、集成性高、成本低等优势现被应用于微纳尺度物质分离分析中,是一种微纳尺度物质分离的有效方法,通过在微流控芯片上设计不同的通道及外部配件提高主动场对微纳尺度物质分离效率。外加场分离技术与微流控技术联用可以实现微纳尺度物质的无损、高效、在线分离。该综述主要概述了近年来在微流控芯片上依托流动场、电场、磁场及声场等外加场分离技术来提高对微纳尺度物质分离效率的研究现状,并将各个外力场对单细胞、微颗粒等微纳尺度物质的分离进行分类介绍,总结各自的优缺点及发展应用,最后展望了外加场分离技术与微流控技术联用在应用于癌细胞的早期筛查、精确分离微尺度物质领域的未来发展前景,并提出联用技术的优势和未来应用等。

Research progress in the application of external field separation technology and microfluidic technology in the separation of micro/nanoscales

The micro/nanoscales concerns interactions of entities with sizes in the range of 0.1-100 μm, such as biological cells, proteins, and particles. The separation of micro/nanoscales has been of immense significance for drug development, early-stage cancer detection, and customized precision therapy. For example, in recent years, rapid advances in the field of cell therapy have necessitated the development of simple and effective cell separation techniques. The isolation technique allows the collection of the required stem cells from complex samples. With the development of materials science and precision medicine, the separation of particles is also critical. The key physicochemical properties of micro/nanoscales are highly dependent on their specific size, shape, functional group, and mobility (based on the charged characteristics), which control their performance in the separation system. The current demand has made the simultaneous innovation of a separation system and an on-line detection platform imperative. Accordingly, various analytical methods involving the use of external forces, such as the flow field, magnetic field, electric field, and acoustic field, have been used for micro/nanoscales separation. Based on the physical and chemical parameters of the separation materials, these analytical methods can select different external force fields for micro/nanoscales separation, enabling real-time, accurate, efficient, and selective separation. However, at present, most of the applied field separation technologies require complex equipment and a large sample amount. This makes it crucial to miniaturize and integrate separation technologies for low-cost, rapid, and accurate micro/nanoscales separation. Microfluidic technology is a representative micro/nanoscales separation technology. It requires only a small volume of liquid, making it cost-effective; its high throughput enables continuous separation and analysis; its fast response in a microchip can allow many reactions; and finally, the miniaturization of the device allows the coupling of multiple detectors with the microchip. With the continuous growth and progress of microfluidic technology, some microfluidic platforms are now able to achieve the non-destructive separation of cells. They also enable on-line detection, offer high separation efficiency, and allow rapid separation for different biological samples. This review primarily summarizes recent advances in microfluidic chips based on flow field, electric field, magnetic field, acoustic field, and field separation technologies to improve the micro/nanoscales separation efficiency. This review also discusses the various external force fields of micro/nanoscales, such as a microparticle, single cell separation of substances classified introduction, and summarizes the advantages and disadvantages of their application and development. Finally, the prospect of the combined application of external field separation technology and microfluidic technology in the early screening of cancer cells and for precise micro/nanoscales separation is discussed, and the advantages and potential applications of the combined technology are proposed.