Abstract: A device for dispensing liquids in drop form of substantially uniform size is provided which includes a container having a dropper tip including a passageway for ingress of air to and egress of liquid from the device, the passageway communicating between the container and an orifice in the dropper tip; means for temporarily reducing the volume of the container; and, disposed within the dropper tip, across the passageway, a microporous composite membrane with pores of a size to resist passage of contaminants. The membrane has a liquophilic component which permits delivery of drops of a liquid to a desired location outside the container and a liquophobic component which is adapted to resist the passage of such liquid but to permit the passage therethrough of air. Both the liquophilic and liquophobic components of the membrane (which intersects the passageway) communicate with the passageway.