Abstract
Lab-on-a-chip (LOC) and micro total analysis systems (μTAS) have been popular in the field of chemical, biological, and even mechanical engineering. Various different types of micropumps have been developed to replace bulky external syringe pumps and to miniaturize the whole analysis systems, but there is little micropump to satisfy all requirements. This paper presents a novel micropumping device to deliver aqueous solution with a simple design composed of diffuser-nozzle mechanism and a bidirectionally-operated micropump of Electro-conjugated fluid (ECF) that is dielectric and functional fluid that can generate strong jet flow between electrode pairs to which high DC voltage is applied in the ECF. The proposed device which has 25.2×22.3×1.9 mm^3 was successfully fabricated by the MEMS process of thick photoresist and electroforming. We proved that dyed water-oil (ECF) interface keeps its boundary while water is oscillating. As a simple way to look into the functionality and performance of the diffuser-nozzle, all micro channels were filled with ECF and the flow rate of ECF was measured. Experimental results demonstrate that this micropump is capable of generating a maximum flow rate of 90μl/min at the applied voltage of 20Hz and 1.8kV. The results show the potential of our novel pumping method for aqueous solution.
