Protocol Cycle Time Optimization on a Microfluidic Cartridge for DNA/RNA Extraction Application

A disposable microfluidic cartridge for DNA/RNA extraction has been developed. Different reagents are used to bind and unbind DNA on the chip used in the cartridge. The extraction of DNA/RNA is based on a particular protocol, which involves the dispensing of different reagents at various flow rates. Dispensing of reagents is controlled by a needle valve which is integrated in the reservoir. With the help of an external actuator the fluid is dispensed to the chip and to the output collector. The flow rate of the fluid is controlled by the speed of the actuator. Protocol cycle time reduction is tried by changing the insert material and the design of the needle plug. Characterization studies for the thin membrane of the needle plug which is between the reservoir and fluidic channel are conducted using PDMS (poly-dimethylsiloxane) and rubber in combination of other materials. PDMS thin membrane is highly elastic and it takes a long time to break and open the valve. Thus, rubber with a combination of other materials is tested to reduce the time to break the membrane and open the valve to release the fluid from the reservoir to the chip. With modified needle plug the cycle time is reduced by about 16 mins.