Kim, Choong Lee, Kangsun Kim, Jong Hyun Shin, Kyeong Sik Lee, Kyu-Jung Kim, Tae Song Kang, Ji Yoon 2024-01-20T23:35:00Z 2024-01-20T23:35:00Z 2021-09-02 2008-03 1473-0197 https://pubs.kist.re.kr/handle/201004/133719 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. English ROYAL SOC CHEMISTRY FLOW MICROCHANNELS MICROCHIP GRADIENTS A serial dilution microfluidic device using a ladder network generating logarithmic or linear concentrations Article 10.1039/b714536e 1 LAB ON A CHIP, v.8, no.3, pp.473 - 479 LAB ON A CHIP 8 3 473 479 scie scopus 000254424300016 2-s2.0-40049099449 Biochemical Research Methods Chemistry, Multidisciplinary Chemistry, Analytical Nanoscience & Nanotechnology Instruments & Instrumentation Biochemistry & Molecular Biology Chemistry Science & Technology - Other Topics Instruments & Instrumentation Article FLOW MICROCHANNELS MICROCHIP GRADIENTS serial dilution microfluidic device logarithmic