Abstract: A plunger-less syringe and method of use is disclosed, wherein the syringe includes an outer housing having a size of a standard 3 cc syringe, and fixedly attached to the to the interior of the outer housing is an interior receptacle for receiving a quantity of blood potentially much less than the volume of the outer housing. The novel syringe has a vent at one end that allows air to escape from the receptacle as blood flows therein. Blood can entirely fill the receptacle, fully displacing the air therein so that no unwanted air remains. The vent includes a filter for preventing blood from exiting the interior receptacle at the vent. A vent cap is provided having a recess for mating with a syringe having a plunger for providing an air flow path between the interior of the plunger-type syringe and the interior receptacle of the plunger-less syringe, wherein blood flow into the receptacle can be controlled.