Applications of a microfabricated device for evaluating sperm function.

Mesoscale structures (microns dimensions, nL-pL volumes) have been designed and fabricated in silicon for use in various analytical tasks. We studied sperm motility and performed sperm selection in channels (80 microns wide x 20 microns deep), branching structures (40 microns wide x 20 microns deep, eight bifurcations), and channels containing barriers (7 microns feature size). Sperm-cervical mucus and sperm-hyaluronic acid interactions were assessed by using appropriate microchannel-chamber structures filled with either cervical mucus or hyaluronic acid. Simultaneous assessment of the potency of different spermicides (e.g., nonoxynol-9, C13G) and spermicide concentrations was achieved with structures comprising chambers containing spermicide connected via channels to a central chamber into which semen was introduced. Semen was also tested for the presence of sperm-specific antibodies by using microchannels filled with human anti-IgG antibody-coated microbeads.