Fabrication of solid phase extraction deoxyribonucleic acid chips based on bio-microelectron-mechanical system technology

A novel solid phase extraction (SPE) deoxyribonucleic acid (DNA) microfluidic chip with siliconpolydimethylsiloxane (PDMS)-glass structure was fabricated based on bio-microelectro-mechanical system (BioMEMS) technology. Four kinds of solid phase matrixes were fabricated on silicon substrates, and the characteristics of these different matrixes and the fabrication procedures were analyzed. Thus the porous oxidized silicon was selected as the optimal solid phase matrix for the purification DNA. The different sealing technologies were contrastively developed for sealing chips to form close channels. The PDMS-glass cover was fabricated by using the optimal pressing method and the silicon substrate with the solid phase matrix was bonding with the PDMS-glass cover to accomplish the preparation of the SPE chip. This SPE chip has been used successfully for the purification of genomic DNA from the rat whole blood. The extracted efficiency of DNA is 23.5 X 10(-9) g/mu L whole blood and the extracted DNA from the whole blood is successfully amplified by polymerase chain reaction (PCR), which can reach the level of the commercial DNA purification kits. Furthermore, the SPE microfluidic chips have the potential to be integrated with other sample preparation microchips, PCR microchip, capillary electrophoresis microchip and so on to achieve detection and analysis of the complex. biological samples.