Patent ID: 8850905

Claim:
A method for sampling dissolved contaminants in liquid, said method comprising: (a) providing a sampling system, having: (i) a first vial having a first seal, said first vial containing a first gas; (ii) a first needle subassembly having a first port and a second port proximal to a distal tip; (iii) a second vial having a second seal, said second vial being substantially filled with a liquid sample that contains dissolved contaminants; (iv) a second needle subassembly having a third port and a fourth port proximal to a distal tip; (v) a syringe having a movable plunger, said syringe having a displacement volume that is bounded by said movable plunger and by an outer wall of said syringe; (vi) a source of gas pressure; (vii) a waste outlet; (viii) a sample outlet; (ix) a plurality of fluidic passageways between said first port of the first needle subassembly, said second port of the first needle subassembly, said third port of the second needle subassembly, said fourth port of the second needle subassembly, said source of gas pressure, said displacement volume of the syringe, said sample outlet, and said waste outlet; (x) a plurality of automatically controlled valves that are in communication with said plurality of fluidic passageways and which, for a predetermined operating mode, establish at least one fluidic pathway of said plurality of fluidic passageways; and (xi) a system controller that determines one of said predetermined operating modes for controlling said plurality of automatically controlled valves; (b) using said first needle subassembly, piercing said first seal of said first vial; (c) using said movable plunger of the syringe, drawing a predetermined first volume of said first gas from said first vial, and evacuating said first volume of the first gas to said waste outlet, thereby establishing a partial vacuum condition inside said first vial; (d) using said second needle subassembly, piercing said second seal of said second vial; (e) using said movable plunger of the syringe, drawing a predetermined second volume of said liquid sample with dissolved contaminants from said second vial, and transferring said second volume of the liquid sample with dissolved contaminants into said first vial, wherein said first volume is substantially equal to said second volume, so that contents of said first vial now are not substantially under pressure or under vacuum conditions; (f) partitioning said liquid sample with dissolved contaminants into a headspace region of said first vial, thereby allowing at least a portion of said dissolved contaminants to enter said headspace region as headspace region vapor; and (g) transferring an aliquot of said headspace region vapor to said sample outlet.