An integrated disposable device for DNA extraction and helicase dependent amplification

• DOI: 10.1007/s10544-009-9391-8
• Publication Date: 2010-01-11T08:00:12Z
• Authors: Madhumita Mahalan...; Jaephil Do; Hussam ALMuayad; Jane Y. Zhang; Catherine M. Klap...
• Keywords: Bacteria; Microfluidics; DNA Helicases; Temperature; DNA; DNA-Directed DNA Polymerase; 01 natural sciences; Culture Media; 0104 chemical sciences; Feces; Nucleic Acid Amplification Techniques; Oligonucleotide Array Sequence Analysis

Here we report the demonstration of an integrated microfluidic chip that performs helicase dependent amplification (HDA) on samples containing live bacteria. Combined chip-based sample preparation and isothermal amplification are attractive for world health applications, since the need for instrumentation to control flow rate and temperature changes are reduced or eliminated. Bacteria lysis, nucleic acid extraction, and DNA amplification with a fluorescent reporter are incorporated into a disposable polymer cartridge format. Smart passive fluidic control using a flap valve and a hydrophobic vent (with a nanoporous PTFE membrane) with a simple on-chip mixer eliminates multiple user operations. The device is able to detect as few as ten colony forming units (CFU) of E. coli in growth medium.