Waters ACQUITY UPC2 - Page 28

November 16, 2016, 715004521 Rev. C
Page 28
Figure 2–5: Step 3: Metering syringe repositions the sample
When the needle is over the injection port, the metering syringe pulls the sample aliquot past port
2 of the injection valve and into the VDD tubing.
Waste
Waste
Auxiliary valve (load position)
Metering syringe
Injection valve (inject position)
Sample
From pump
To col umn
Sample loop
Liquid mobile phase (CO
2
)
Gas mobile phase (CO
2
)
Air gap
Buffer volume
Sample
Weak wash
Sample