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

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 mu L. 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. (C) 2009 Elsevier Ireland Ltd. All rights reserved.