Fluid separatory device

Claim 1

A method for separating a fluid mixture into a plurality of fluid phases of differing densities within a syringe having a barrel, including a sidewall and an end wall, inlet means in a wall of the barrel for admitting a fluid mixture thereto; a plunger slidably disposed in the barrel in fluidtight relation to the sidewall thereof so as to form a chamber of variable volume in the barrel, means for selectively closing the inlet means; conduit means on the plunger for providing unidirectional fluid flow through the plunger from the chamber; and a receptacle on the plunger surrounding the conduit means and downstream thereof, the method comprising: a. drawing a fluid mixture to be separated through the inlet means and into the chamber, b. mixing the fluid mixture in the chamber with a chemical means for facilitating the separation of a fluid mixture into a plurality of fluid phases of differing densities, c. closing the inlet means, and thereafter d. holding the syringe in a vertical position with the plunger above the defined chamber until the fluid mixture separates into a plurality of phases of differing densities, e. moving the plunger downward into the chamber toward the interface resulting from separation of the mixture and simultaneously venting the receptacle to atmosphere, whereby the uppermost liquid phase flows through the conduit means into the receptacle; f. terminating the downward motion at a point in said chamber not below the interface; g. and thereafter withdrawing the plunger, receptacle and the liquid phase therein from the barrel.

Claim 2

A method for separating a fluid mixture into a plurality of fluid phases of differing densities within a syringe having a barrel, including a sidewall and an end wall, inlet means in a wall of the barrel for admitting a fluid mixture thereto; a plunger slidably disposed in the barrel in fluidtight relation to the sidewall thereof so as to form a chamber of variable volume in the barrel, means for selectively closing the inlet means; conduit means on the plunger for providing unidirectional fluid flow through the plunger from the chamber; and a receptacle on the plunger surrounding the conduit means and downstream thereof, the method comprising: a. drawing a fluid mixture to be separated through the inlet means and into the chamber, b. mixing the fluid mixture in the chamber with a chemical means for facilitating the separation of a fluid mixture into a plurality of fluid phases of differing densities, c. closing the inlet means, and thereafter d. holding the syringe in a vertical position with the plunger above the defined chamber until the fluid mixture separates into a plurality of phases of differing densities, e. moving the plunger downward into the chamber toward the interface resulting from separation of the mixture and simultaneously venting the receptacle to atmosphere, whereby the uppermost liquid phase flows through the conduit means into the receptacle; f. terminating the downward motion at a point in said chamber not below the interface; g. and thereafter withdrawing the plunger, receptacle and the liquid phase therein from the barrel.