A serial dilution microfluidic device using a ladder network generating logarithmic or linear concentrations.
In this paper, we propose a serial dilution microfluidic chip which is able to generate logarithmic or linear step-wise concentrations. These concentrations were generated via adjustments in the flow rate of two converging fluids at the channel junctions of the ladder network. The desired dilution ratios are almost independent of the flow rate or diffusion length of molecules, as the dilution device is influenced only by the ratio of volumetric flow rates. Given a set of necessary dilution ratios, whether linear or logarithmic, a serial dilution chip can be constructed via the modification of a microfluidic resistance network. The design principle was suggested and both the logarithmic and linear dilution chips were fabricated in order to verify their performance in accordance with the fluorescence intensity. The diluted concentrations of a fluorescein solution in the microfluidic device evidenced relatively high linearity, and the cytotoxicity test of MCF-7 breast cancer cells via the logarithmic dilution chip was generally consistent with the results generated with manual dilution.
Kim
Choong
C
Nano-Bioresearch center, Korea Institute of Science and Technology, Songbuk Gu, 136-791, Seoul, Korea.
Lee
Kangsun
K
Kim
Jong Hyun
JH
Shin
Kyeong Sik
KS
Lee
Kyu-Jung
KJ
Kim
Tae Song
TS
Kang
Ji Yoon
JY
D045744:Cell Line, Tumor; D005453:Fluorescence; D006801:Humans; D044085:Microfluidics / Q000295:instrumentation*