On-chip DNA preconcentration in different media conductivities by electrodeless dielectrophoresis.
Electrodeless dielectrophoresis is the best choice to achieve preconcentration of nanoparticles and biomolecules due to its simple, robust, and easy implementation. We designed a simple chip with microchannels and nano-slits in between and then studied the trapping of DNA in high conductive medium and low conductive medium, corresponding to positive and negative dielectrophoresis (DEP), respectively. It is very important to investigate the trapping in media with different conductivities since one always has to deal with the sample solutions with different conductivities. The trapping process was analyzed by the fluorescent intensity changes. The results showed that DNA could be trapped at the nano-slit in both high and low conductive media in a lower electric field strength (10 V/cm) compared to the existing methods. This is a significant improvement to suppress the Joule heating effect in DEP related experiments. Our work may give insight to researchers for DNA trapping by a simple and low cost device in the Lab-on-a-Chip system.
Shunbo
S
Li
Department of Physics and Nano Science and Technology Program, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong.
Ziran
Z
Ye
Department of Physics and Nano Science and Technology Program, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong.
Yu Sanna
YS
Hui
Environmental Science Program, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong.
Yibo
Y
Gao
College of Communication Engineering, Chongqing University , Chongqing 400044, China.
Yusheng
Y
Jiang
Weijia
W
Wen