Department of Biomedical Engineering, The Catholic University of America, Washington, DC 20064, USA.
J Mater Chem B. 2021 Apr 21;9(15):3258-3283. doi: 10.1039/d1tb00045d. Epub 2021 Mar 16.
The integration of membranes in microfluidic devices has been extensively exploited for various chemical engineering and bioengineering applications over the past few decades. To augment the applicability of membrane-integrated microfluidic platforms for biomedical and tissue engineering studies, a biologically friendly fabrication process with naturally occurring materials is highly desired. The in situ preparation of membranes involving interfacial reactions between parallel laminar flows in microfluidic networks, known as the flow-assembly technique, is one of the most biocompatible approaches. Membranes of many types with flexible geometries have been successfully assembled inside complex microchannels using this facile and versatile flow-assembly approach. Chitosan is a naturally abundant polysaccharide known for its pronounced biocompatibility, biodegradability, good mechanical stability, ease of modification and processing, and film-forming ability under near-physiological conditions. Chitosan membranes assembled by flows in microfluidics are freestanding, robust, semipermeable, and well-aligned in microstructure, and show high affinity to bioactive reagents and biological components (e.g. biomolecules, nanoparticles, or cells) that provide facile biological functionalization of microdevices. Here, we discuss the recent developments and optimizations in the flow-assembly of chitosan membranes and chitosan-based membranes in microfluidics. Furthermore, we recapitulate the applications of the chitosan membrane-integrated microfluidic platforms dedicated to biology, biochemistry, and drug release fields, and envision the future developments of this important platform with versatile functions.
在过去的几十年中，膜在微流控器件中的集成已经被广泛应用于各种化学工程和生物工程应用。为了提高膜集成微流控平台在生物医学和组织工程研究中的适用性，人们非常希望使用具有天然材料的生物友好型制造工艺。在微流控网络中平行层流之间的界面反应中就地制备膜的方法，即流动组装技术，是最具生物相容性的方法之一。使用这种简单而通用的流动组装方法，可以在复杂的微通道内成功组装出具有灵活几何形状的多种类型的膜。壳聚糖是一种天然存在的多糖，以其显著的生物相容性、生物可降解性、良好的机械稳定性、易于修饰和加工以及在近生理条件下成膜能力而闻名。通过微流控中的流动组装的壳聚糖膜是独立的、坚固的、半透的，并且在微观结构中排列整齐，对生物活性试剂和生物成分（例如生物分子、纳米粒子或细胞）具有高亲和力，从而便于微器件的生物功能化。在这里，我们讨论了在微流控中壳聚糖膜和壳聚糖基膜的流动组装方面的最新进展和优化。此外，我们回顾了专门用于生物学、生物化学和药物释放领域的壳聚糖膜集成微流控平台的应用，并展望了这个具有多功能的重要平台的未来发展。
