A Plug‐and‐Play Volume Minimizing Micromixer

ABSTRACT Microscale fluid mixing has numerous applications where rapid and efficient mixing is required, including drug discovery, bio‐analysis and point‐of‐care diagnostics. Conventional soft lithography processes, however, make the integration of robust and reliable mixing difficult to implement in practice, especially across different flow rates. Here a 3D‐printed plug‐in micromixer designed for rapid and modular integration with microfluidic devices that addresses long‐standing integration challenges for micromixing in microfluidic devices is presented. The micromixer is based on the split‐and‐recombine (SAR) channel topology employing an optimized 3D geometry, minimizing internal volume and fluidic resistance. A micromixer with 60‐µm internal channels is fabricated and experimentally tested, demonstrating efficient mixing while maintaining a reliable seal with a PDMS microfluidic device. Accordingly, the modular micromixing device enhances the efficiency and usability of microfluidic systems, offering a promising solution for biomedical and analytical applications. This conceptually elegant plug‐in approach represents a unique advance in the practical integration of 3D printed functionality with microfluidics devices.