Separation of double-stranded DNA fragments in plastic capillary electrophoresis chips by using E99P69E99 as separation medium.

The separation of double-stranded DNA (dsDNA) fragments in polymethylmethacrylate (PMMA) capillary electrophoresis (CE) chips by using E99P69E99 as a separation medium has been demonstrated. The PMMA CE chips were simply manufactured by micromachining and adhesive tape sealing. To make the separation channel compatible with the separation medium, a dynamic nonionic surfactant coating procedure was developed, which made the plastic separation channel sufficiently hydrophilic to allow the separation medium to fill the channel by capillary action. Subsequent separation of DNA fragments was successful with a separation efficiency of the order of 10(4) theoretical plates over an effective separation distance of 1.5 cm. By using an applied electric field strength of 200 V/cm, the separation of low DNA mass ladder was completed within 5 min. The simple coating procedure, together with the self-assembled viscosity-adjustable separation medium, should be useful to meet some of the essential requirements for developing single-use disposable CE chips. Coating the channels with polymer blends of PMMA and the separation medium also showed promise.