Portable plastic syringe as a self-actuated pump for long-distance uniform delivery of liquid inside a microchannel and its application for flow-through polymerase chain reaction on chip

Abstract

A portable plastic syringe was used as a self-actuated pump for uniform delivery of liquid inside a microchannel over a distance of more than 2 meters at a controllable flow rate and without utilizing external electrical power and bulky pumping apparatus. The reliability of the plastic syringe as a potential self-actuator was investigated by performing a flow-through polymerase chain reaction (PCR) on a microdevice fabricated using poly(methylmethacrylate) (PMMA). Liquid flowed at a uniform rate inside the PMMA microchannel in a highly controllable manner even under high-temperature conditions and without the generation of bubbles, and the flow rate was readily adjusted as necessary by varying the operation parameters such as the length of the outlet silicone tube, channel dimension, and initial syringe pressure. A 230 bp plasmid vector obtained from E. coli and a D1S80 locus obtained from a human genomic DNA were successfully amplified on a PMMA microdevice equipped with the disposable plastic syringe as a self-actuated micropump.