Photo-switchable microvalve in a reusable Lab-on-a-disc

This contribution describes for the first time the fabrication and the performance of a reversible ionogel microvalve in-situ photopolymerised into a reusable disc platform for fluid control. During storage and spinning, the swollen microvalve provides a permanent liquid barrier due to the special chemical characteristics of the ionogel. The microvalve is easy actuated using a white light LED allowing open of the channel at a desired time. The actuation mechanism is chemically reversible when an acid solution is provided to the microvalve. Here a perpendicular microchannel, connected to the valve from behind, is used to ensure the re-swelling of the ionogel and therefore reusability of the Lab-on-a-disc.