Detection of Periodontal Pathogens Based on an Integrated Continuous Flow PCR and Capillary Electrophoresis Microfluidic Chip

Continuous-flow PCR (CF-PCR) can realize rapid DNA amplification because of the high temperature variation rate. However, off-line detection methods for PCR may induce cross contamination. To overcome this problem, we herein fabricated an integrated CF-PCR and electrophoresis microfluidic chip. The optimal voltage applied in the electrophoresis part of the microfluidic chip was achieved by simulation in COMSOL. Coating the inside wall of the microchannel can inhibit electroosmotic flow and improve the resolution for DNA fragments. The temperature distribution of the serpentine part can meet the PCR and has no obvious suppressive effect on sample separation. Finally, we have performed the amplification of target genes forPorphyromonas gingivalis,Tannerella forsythia, andTreponema denticolaand detected the corresponding PCR products in the microfluidic chip within 11 min. Such work provides a new method for the rapid detection of bacteria.Keywords:capillary electrophoresis;periodontal pathogens;continuous flow PCR;microfluidic chip;fluorescence detection