A versatile microfluidic intermediate delivery reservoir for isolating fluid dynamics in serially interconnected microfluidic networks

Background

Serially interconnected microfluidic devices enable advanced applications such as multi-step chemical processing and multi-organ-on-chip systems. However, managing these systems presents challenges due to interdependent fluid dynamics in their connecting channels, where even minor disturbances can propagate throughout the network, affecting overall system performance.

Methods

This study introduces a microfluidic-based intermediate delivery reservoir (mIDR) designed to decouple flow interdependencies between serially connected devices while preserving essential microfluidic features, such as consistent liquid residence time. When integrated with a pneumatic pump, the mIDR enables precise liquid pressure regulation and independent control of both inlet and outlet flow rates. Its wedge-shaped open-channel structure generates capillary force gradients, enhancing liquid transfer efficiency. Experimental validation using time-sensitive enzymatic reactions confirms its ability to maintain laminar flow characteristics, isolate crosstalk, and stabilize interconnected microfluidic device operation.

Significant findings

The open-channel design of the mIDR expands its versatility, allowing for additional functionalities such as debubbling and direct accessibility, which combine the advantages of both open and closed microfluidic systems. This innovation provides a robust and flexible solution for controlling fluid dynamics in complex microfluidic networks, offering improved reliability and efficiency for multi-step (bio)chemical processes.