A microfluidic method for removal of the zona pellucida from mammalian embryos

Many in vitro procedures involve manipulation of the zona pellucida (chimerics, transgenics, biopsy). We have demonstrated a microfluidic channel network to precisely control (spatially and temporally) the delivery of chemical treatments for the removal of the zona pellucida. Building devices in polydimethylsiloxane (PDMS) with channel dimensions on the same order as that of the embryo diameter (∼120 µm) allows precise control of the local fluid environment. The system uses pressure driven flows to control embryo positioning, embryo movement, and plug formation. Zona removal is achieved by briefly washing a plug of lysing agent (acid Tyrode's medium) over the embryo.