OBJECTIVE or GOAL
Perform an HPLC injection accuracy test.
Injection Volume Accuracy
Note: To improve the accuracy of this test, handle the vial with forceps to ensure that the vial is as clean as possible.
1. Fill a standard vial with methanol or water.
2. Seal the vial with a Teflon Septum and cap.
3. Zero the analytical balance, carefully weigh the vial, and record the weight.
4. Place the vial in the carousel and set the flow rate to 1.0mL/min.
5. Program the system to make six 50µl injections from the vial. (Use a run time of approximately one minute or less)
6. Weigh the vial after the last injection and record that weight.
Using one of the following equations (depending on the solvent used), calculate the average amount injected per injection.
((W1-W2) /6) x (1/density of solvent) = µl injected
Density of Methanol is 0.7890
((W1-W2) /6) x 1.2687 = µl injected
Density of Water is 1.0000
((W1-W2) /6) x 1.0000 = µl injected
RESULTS: 50µl +/- 1µl
This is commonly referred to as a 'lift test' by Waters engineers.