Microfluidic systems on porous substrates, including paper-based analytical platforms, have attracted significant attention recently, primarily attributed to their diversified applications, ranging from bioanalytical devices for healthcare technologies to green energy generation and flexible electronics. In this short Review, we attempt to provide a concise overview about the fundamental premises of functionalities of these devices, starting from the understanding of flow in single one-dimensional conduit. This can be extended to more-complex systems, where an intrinsic capillary action offers the necessary provisions for continuous maintenance of heterogeneous flow over multiple spatiotemporal scales, which essentially facilitates the needs of specific applications. We discuss a few specific applications as demonstrative examples that are solely triggered by the intrinsic capillary action of the porous media. These specific examples delineate the fact that flexible architecture of the devices, in combination with the inherent capillary-driven phenomena, makes it suitable to meet the desired user-specific demands at affordable costs, rendering them immensely suitable for the low-resource-settings environment.

中文翻译：

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毛细管驱动运输介导的多孔基质上的微流控。

多孔基材上的微流体系统，包括基于纸张的分析平台，最近引起了广泛的关注，这主要归功于其多样化的应用，从医疗技术的生物分析设备到绿色能源生产和柔性电子产品。在这篇简短的综述中，我们将从对单个一维导管中的流量的理解入手，简要概述这些设备功能的基本前提。这可以扩展到更复杂的系统，在该系统中，固有的毛细作用为在多个时空范围内连续保持非均质流动提供了必要的条件，从而从根本上满足了特定应用的需求。我们将讨论一些特定的应用，作为仅由多孔介质固有的毛细管作用触发的演示示例。这些特定示例说明了以下事实：设备的灵活架构与固有的毛细管驱动现象相结合，使其能够以可承受的成本满足所需的特定于用户的需求，从而使其非常适合于资源匮乏的环境。