Rapid size determination of PCR amplified DNA by beads-based dielectrophoretic impedance spectroscopy

This paper reports a new method to determine the size of DNA amplified by polymerase chain reaction (PCR). After PCR, the amplified DNA was attached on dielectric microbeads, then, the DNA labeled microbeads were trapped on a microelectrode by dielectrophoresis (DEP). The size of the DNA was determined by measuring frequency dependent impedance of the trapped microbeads as an impedance spectroscopy. The size of various DNAs, 142, 204, 391, 796 bp, were successfully identified from the impedance spectrograms. This method determines DNA size in 20 min after PCR.