DNA-based biosensors usually use a DNA probe to detect the presence of target DNA for a specific pathogen. The underlying process in these biosensors relies on DNA hybridization in which one strand of DNA matches up with its complementary strand (target DNA) to form a double-stranded molecule. Thus, hybridization is a key process in a DNA biosensor, and the hybridization kinetics is an important index in this process.
This hybridization process is often limited by a passive diffusion process of the large DNA molecules in the static DNA sample solution. To improve the sensitivity and to lower the response time of the micro DNA biosensor, we design and fabricate an active thermal bubble actuator to enhance the DNA hybridization.
Picture of (a) the packaged micro device, (b) the close-up view of the specially designed
non-uniform micro heater
Micro Bubble actuator (Bubble dynamics video using high speed CCD camera)
Submicron bubble actuator (Bubble dynamics video using high speed CCD camera)
Y.K. Lee, U.C. Yi, F.G. Tseng, C.J. Kim and C.M. Ho, "Fuel Injection by a Thermal Microinjector," Proceedings of MEMS, ASME International Mechanical Engineering, Nashville, Tennessee, Nov, pp. 419-425. 1999
P.G. Deng, Y.K. Lee and P. Cheng, "Design and Characterization of A Micro Single Bubble Actuator", Transducer'03 (the 12th Intl. Conf. on Solid-State Sensors, Actuators and Microsystems), Boston, pp.647-650, 2003.
P. G. Deng, Y.K. Lee, P. Cheng, Micro Single Bubble Generation and Behavior Under Pulse Heating, International Journal of Heat and Mass Transfer, Vol. 46, No. 21, pp.4041-4050, 2003.
