Aspirating syringe

An aspirating syringe, comprising;

• (a) a plastic syringe barrel having an exterior wall and an inner surface, and a leading and a trailing end, said inner surface and said ends defining a hollow interior chamber and a predetermined volume, said leading end having an opening extending through a hub, said trailing end terminating at an outer rim;
• (b) a plastic plunger operative in said barrel through said barrel trailing end to define said hollow interior chamber and said predetermined volume, said plunger extending longitudinally within and beyond said barrel leading end and being movable in said barrel inwardly toward said leading end and outwardly away from said leading end, thereby varying the volume of said barrel interior chamber, said plunger having a sealing end receivable inside said barrel to substantially seal said hollow interior chamber and a thumb-receiving end outside said barrel, wherein said plunger sealing end comprises an elastomeric gasket comprising a body with forward and rearward ends and first and second annular flanges positioned circumferentially at the forward and rearward ends of the body, the flanges being separated by an annular space intermediate the body portion and the barrel inner surface, wherein the gasket further comprises an annular projection extending from each flange, each projection being of reduced thickness relative to the thickness of each flange and providing a contact point with the barrel inner surface when said plunger sealing end is received in said barrel chamber, thereby enabling low friction between said gasket and said barrel inner surface during forward and rearward movement of said gasket;
• and
• (c) an outward biasing means coiled around said plunger between said barrel trailing end and said plunger thumb-receiving end to bias the plunger outwardly from the syringe barrel upon advancement of the plunger into said barrel.