Abstract
Three zoom circular Polymer Chain Reaction ﹙PCR﹚ chip is disclosed. This chip are composed of a substrate, a fluid layer and an air pressure layer. Three ring-shaped heaters with temperature sensor on each of it are adapted on the substrate. On the fluid layer there is a ring shaped flow pass. And, on the air pressure layer there are three ring-shape air rooms. During the PCR process, a reaction fluid is putted into the ring shaped flow pass with the heater adjusted to a defined temperature. Regulate the air pressure unit to adjust air inlet in these air rooms, it may further controls flow direction of the reaction fluid in the ring shaped flow pass. The reaction fluid flows in these three heaters to complete the PCR process.