A passive micromixer for enzymatic digestion of DNA

A passive micromixer with zigzag geometry is demonstrated in this work to perform simultaneously mixing of a restriction enzyme with DNA and digestion of DNA. The total length required for complete mixing is estimated by simulation. The micromixer is fabricated from an imide-based photoimageable dry-film using flexible printed circuit technology that allows easy integration of the microdevice in more complex Lab-on-a-Chip (LoC) platforms. When heated at 37 °C, the micromixer achieves both complete mixing of the reagents and DNA digestion with restriction enzymes within 2.5 min, i.e., a time comparable to the incubation step needed in conventional digestion systems. Thus, it renders further incubation unnecessary and is proved a valuable component of LoC systems for diagnostic purposes.