Control of Plural Number of Arrayed Microvalves using pH-responsive Hydrogel

We present a pH-responsive microvalve array system and new multiplexing technology that facilitates the operation of microvalve arrays using pH-responsive hydrogel microspheres. By incorporating these microspheres inside of the arrayed microvalve polydimethylsiloxane (PDMS) platform, we produced pH-responsive arrayed microvalves with 'Open' and 'Close' operations carried out by the multiphase laminar streams of pH solutions. The constructed arrayed microvalves were adequately controlled by the multiphase pH-buffer streams with the widths controlled only by the pressure of the pH-buffer solutions.