Before the Analysis

Sample Preparation

• Filter samples before injection with a Syringe and Filter.

  • Syringe filters can be found in the cupboard in the weighing room.
  • Clean syringes can be found in sealed packets in the cupboard under the HPLC.

Pre-Run

1. Check the indicator lights on the Autosampler, Pump, Column, VWD and MS are not Red.

   Orange, Flashing Orange or Off are OK.

2. Check the valve near the ESI on the MS is open (handle in line with pipe) and is connected to L on the nearby block (shown below)

   

   Check that the pipe is connected to the port marked “L” to the left of this image, not to the port marked “H”

3. Check the levels of the bottles on the front of the MS. Tap the bottles to disturb the liquid if the level is not obvious.

4. Check the levels of the waste bottles in the following locations:

   • Beneath the bench below the Pump/Autosampler/Eluent stack
   • Beneath the bench below the MS and behind the Vacuum Pumps
   • Behind the MS

5. Check there is pressure in the Collision Gas Bottle behind the MS, and record the pressure

6. Check the 3 Exhaust Pipes are entering the Extractor for the Graphite Furnace

7. Return to the front of the instrument

8. Fetch some blue towel.

9. Open the Ionisation Chamber of the MS and spray 50% IPA around (but not into) the metal surfaces of the inlet orifice.

10. Spray the inside of the Ionisation Chamber door and wipe with the blue towel.

11. Close the Ionisation Chamber.

12. Open Mass Hunter Workstation Data Acquisition.

13. Check the pressures on the top right of the screen are within the following values:

    Rough Vac	< 4.4×10 0
    Quad Vac	1×10 −5 - 4×10−5
    TOC Vac	2×10 −7 - 4×10 −7

14. Check sufficient eluent is present in the eluent bottles being used for the run.

15. Check that the Quat. Pump is aware of the level of eluent in the bottles. To do this:

    1. Right click on the Quat. Pump panel of the Instrument Status window in MassHunter. <could use image here>

    2. Select Bottle Fillings from the menu.

    3. Under Actual Volume, ensure the value reflects the volume of eluent actually present in the bottle.

       

       The “Bottle Fillings” window

    4. Click OK.

    Repeat the above steps when Changing Eluent (see below)

Changing Eluent

To change an eluent, perform the following steps:

1. Right click on the QTOF panel of the Instrument Status window in MassHunter and select LC → Waste from the menu.

   

   The Instrument Status window

2. In the Method Editor, under Quat. Pump, set the Flow Rate to 0.000 mL/min and press Enter⏎

3. Swap the the eluent bottles. Try to swap similar eluents; for example, replace Ammonium Formate with Ammonium Acetate.

   • The Lids on the bottles do not need to be tight.

4. Open the valve behind the door on the front of the Pump.

5. Set the level of any solvents that weren’t changed to 0% and enable the eluents that were changed.

6. Set the Flow Rate to 1.000 mL/min and press Enter⏎

7. Check the pressure in the Column does not rise above 0 Bar. If it does, check the valve at the front of the Pump is open.

8. Set the Flow Rate to 5.000 mL/min and press Enter⏎

9. After 5 minutes, set the Flow Rate to 0.000 mL/min and press Enter⏎

10. Close the valve on the front of the Pump and close the door.

A method can be setup for flushing and equilibrating the column as part of the Worklist if desired