Microfluidic chip of fast DNA hybridization using denaturing and motion of nucleic acids

This study presents the effect of fluidic temperatures and velocities on improving DNA hybridization. The efficiency of hybridization could be improved by introducing elevated temperature in the hot region and velocity in the cold region. Compared with the conventional methods, this hybridization microchip was able to increase the hybridization signal 4.6-fold within 30 min. The 1.4-kb single-stranded target DNA was tested. The increasing tendency of the fluorescence intensity was apparent when the temperature was higher than 82°C, and the fluorescence intensity reached an asymptotic value at T >90°C. A mathematical model was proposed to relate the fluorescence intensity of DNA hybridization with the hot-region temperature and the cold-region velocity. Based on these results, the new hybridization chip with the processes of temperature and velocity differences will improve efficiency of DNA detection. The microchip combined with hot-region temperature and cold-region bulk flow velocity effects could provide additional efficiency in DNA hybridization.