A microreactor using surface acoustic wave as energy source

A microreactor is a key operation unit in a microfluidic device. However, lots of biochemical reactions do not occur at room temperature. Thus, a heating unit in these microfluidic devices is indispensable. A new microreactor with surface acoustic wave (SAW) as an energy source is presented. The microreactor has three elements, including surface acoustic wave heating source, two PDMS micro-vessels and a heat-transfer sheet metal. A glycerin microfluid in the PDMS micro-vessel on the piezoelectric substrate was heated by SAW radiation. The heat was then transferred to the reactants in the PDMS micro-vessel on the sheet metal. The heating effect of the microreactor was verified by melting solid paraffin and color development reaction. The results show that the microreactor can raise the temperature of reactants from 16.1°C of room temperature to higher than 60°C, which is enough for lots of biochemic reactions occurring at about 40°C. The results also show that the microreactor can greatly improve the reaction velocity of starch color development reaction.