Centrifugal microfluidic system for a fully automated N-fold serial dilution

We present an innovative tool for a fully automated N-fold serial dilution with a choice of N = 2, 5, 10 on a centrifugal microfluidic device. Individually addressable, reversible diaphragm valves are integrated on the disc for the automatic control of the fluidic transfer. Two metering zones are designed with three microfluidic chambers with the volume of 1 pi, 3 pi and 5 pi to meter the samples or the dilution buffer. The pre-programmed operation of the valves enabled the automatic serial dilution with the choice of the dilution factor of 2, 5, or 10 at each dilution steps. The samples prepared on the disc with various serial dilution factor showed excellent accuracy (R-2 > 0.970). The automatic serial dilution disc could be an essential tool in the laboratory to replace the time-consuming and iterative pipetting especially when the sample volume is limited. (C) 2017 Elsevier B.V. All rights reserved.