A Micro Cell Counter Integrated with Oxygen Micropump

This paper describes fabrication of a micro cell counter integrated with an oxygen micropump and Sephadex G-25 beads counting experiment. The device utilized a phototransistor, microwindow, and light source of microscope for beads detection. Microheater and microchannel were used for pumping and guiding of beads to the microwindow. Counting capability of the device was tested with a peristaltic pump and the measured signals (${\sim}10\;mV$) with oscilloscope showed peak shape when beads passed the microwindow. Pumping of beads by the oxygen micropump was carried out by heating paraffin, which enveloped manganese dioxide (catalyst), to trigger the decomposition of hydrogen peroxide into water and oxygen. It lasted for 5 min with $7\;{\mu}l$ of wt. 30 % hydrogen peroxide. Beads counting by oxygen micropump showed peaks ($2{\sim}20\;mV$) with $30\;{\mu}l$ of beads sample and the number of peaks by magnitude was acquired.