An integrated microfluidic device for DNA purification and PCR amplification of STR fragments.

Department of Chemistry, University of Virginia, Charlottesville, VA 22904, USA.
Forensic Science International: Genetics (Impact Factor: 3.86). 04/2010; 4(3):178-86. DOI: 10.1016/j.fsigen.2009.02.010
Source: PubMed

ABSTRACT This work presents the integration of DNA extraction from complex samples and PCR amplification of STR fragments in a valveless, glass microdevice, using commercially available kits and instrumentation. DNA extraction was performed using a microchannel packed with a silica solid phase and a standard syringe pump as a single pressure source driving the extraction process, followed by integrated, online microchip amplification of STR fragments in a total volume of 1.2 microL. Reported characteristics important to this work include the capacity of the device for purification of DNA from a complex biological sample (whole blood) and the timing of DNA elution from the silica solid phase for successful downstream PCR amplification by placement the microdevice into a conventional thermocycler. Potential application of this microdevice to forensic genetic analysis was demonstrated through the preliminary extraction of DNA from semen, followed by an integrated, multiplexed, on-chip amplification that yielded detectable STR amplicons. By utilizing conventional laboratory equipment, the device presented exploits the benefits of microfluidic systems without complex control systems.

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