Cumulus removal and single mammalian oocyte trapping on a microfluidic device

We report an improved method to remove cumulus cells from cumulus-oocyte complexes (COCs) and subsequently capture individual denuded oocytes using a microfluidic device with the flow driven by a combination of negative pressure and gravity. The device consists of two poly-dimethylsiloxane (PDMS) layers, forming a digesting chamber and a pit-array area. COCs are first removed of cumulus cells by hyaluronidase in the digesting chamber, then single denuded oocytes are transported and lodged in individual pits. Multiple COCs can be concurrently processed in the microfluidic cumulus removal (CR) device to produce individual denuded oocytes for subsequent fertilization. ? 2009 CBMS.EI