On-demand, reversible, and reusable finger-actuated air pumping module for fully integrated modular microfluidics

Modular microfluidics can reduce the time and cost of microfluidic chip development; however, reliance on commercial pumping systems limits widespread use for prototyping. In this study, we present a modular pump, a finger-actuated air pumping module (FAPMO), which enables on-demand, repeated, reversible, and versatile operation of modular microfluidics. The FAPMO features integrated microvalves with a pushbutton that enables repeated operations in both expulsion and suction modes, and coupling the FAPMO with a reservoir module facilitates versatile use. By integrating a polydimethylsiloxane (PDMS)-based pumping component into a modular cage with interfacing film channels, the FAPMO applies pressure to other modules. After characterizing the pressure driven by the FAPMO and the flow velocity of a reagent from the reservoir module, we demonstrate its application in the purification of bacterial DNA. By assembling and operating modular blocks for reagent injection, mixing, washing, and elution, we successfully purified DNA from a lysate at concentrations as low as 10⁴ CFU/mL of Escherichia coli O157:H7. The FAPMO is expected to be widely applicable in modular microfluidics, enabling straightforward proof of concept in biological and chemical applications.