Full Loop Injections - Waters 2707 Operator's Manual

Full loop injections

In the standard configuration, full loop injections yield maximum possible
reproducibility < 0.3% RSD but not necessarily maximum accuracy, because
loop volume is typically specified with an accuracy of ± 10%. Typical sample
usage is 330 µL (3 × loop overfill + 30 µL flush volume for the needle). The
minimum flush volume of 30 µL is recommended; you can program smaller
flush volumes, but they decrease performance.
This is the full loop injection sequence:
1. The injection valve moves to the Inject position, and the sample needle
and air needle enter the well or vial. When the instrument method
enables sample pressurization, the air needle applies headspace
pressure to prevent air or vapor bubbles from forming during sample
aspiration.
Syringe
1-8 Understanding Operating Principles
Buffer tubing
INJECT
Needle
Sample
Sample loop
Pump
Column