Microfluidic chip for high efficiency DNA extraction

Abstract

A high efficiency DNA extraction microchip was designed to extract DNA from lysed cells using immobilized beads and the solution flowing back and forth. This chip was able to increase the extraction efficiency by 2-fold when there was no serum. When serum existed in the solution, the extraction efficiency of immobilized beads was 88-fold higher than that of free beads. The extraction efficiency of the microchip was tested under different conditions and numbers of E. coli cells. When the number of E. coli cells was between 10(6) and 10(8) in 25 microl of whole blood, the extraction efficiency using immobilized beads was only slightly higher than that using free beads (10(0) to 10(1) fold). When the number of E. coli cells was in the range 10(4) to 10(6) in 25 microl of whole blood, the extraction efficiency of immobilized beads was greater than that of the free beads (10(1) to 10(2) fold). When the number of E. coli cells was lower, in the range 10(3) to 10(4) in 25 microl of whole blood, the extraction efficiency of immobilized beads was much higher than that of the free beads (10(2) to 10(3) fold). This study indicated that DNA could be efficiently extracted even when the number of bacterial cells was smaller (10(5) to 10(3)). This microfluidic extraction chip could find potential applications in rare sample genomic study.

Purification of Nucleic Acids in Microfluidic Devices

“…21 This process is analogous to commercially available ZipTips in which the reversed-phase silica resin is fixed at the end of the pipet tips. The fixed phase enables peptide and protein purification by simply pipetting repeatedly through the phase.…”

Blood-on-a-Chip

“…Following this demonstration, there have been several attempts to integrate multiple functions onto a single chip ( Figure 6). Several reports have shown integration of simple functions on microfabricated devices that can perform lysis of cells (107), quantitative biochemical analysis of soluble components at the single-cell level (108), analysis of nucleic acids (109)(110)(111), or proteomic analysis (102). Gene transfection in cells sorted in a highly parallel format (112) has been used to alter specific cells for cell therapy purposes.…”

3D-Printed Microfluidic Platform Enabling Bacterial Preconcentration and DNA Purification for Molecular Detection of Pathogens in Blood

“…A similar trend was observed using qPCR. The cell walls of Gram-positive bacteria are thicker than those of the Gramnegative ones [7] and is hard to lyse by thermocycling of PCR. As a result, even at 10 3 CFU/mL, the concentration of gDNA released from the lysed cells was not sufficient to be detected using PCR-gel electrophoresis and qPCR.…”