Abstract
Droplet microfluidics has appealed to many interests for its capability to epitomize cells in a microscale environment and it is also a forceful technique for high-throughput single-cell epitomization. A dielectrophoretic microfluidic system imitates the oviduct of mammals with a microchannel to achieve fertilization in vitro (IVF) of an imprinting control-region (ICR) mouse. We applied a microfluidic chip and a positive dielectrophoretic (p-DEP) force to capture and to screen the sperm for the purpose of manipulating the oocyte. The p-DEP responses of the oocyte and sperm were exhibited under applied bias conditions (waveform AC 10 Vpp, 1 MHz) for trapping 1 min. The insemination concentration of sperm nearby the oocyte was increased to enhance the probability of natural fertilization through the p-DEP force trapping. A simulation tool (CFDRC-ACE+) was used to simulate and to analyze the distribution of the electric field. The DEP microfluidic devices were fabricated using poly (dimethylsiloxane) (PDMS) and ITO (indium tin oxide)-glass with electrodes. We discuss the requirement of sperm in a DEP microfluidic chip at varied concentrations to enhance the future rate of fertilization in vitro for an oligozoospermia patient. The result indicates that the rate of fertility in our device is 17.2 ± 7.5% (n = 30) at about 3000 sperms, compatible with traditional droplet-based IVF, which is 14.2 ± 7.5% (n = 28).