How to tune up for APCI or ESCI mode - WKB7804
Article number: 7804
OBJECTIVE or GOAL
Tune source for APCI or ESCI mode.
ENVIRONMENT
- MassLynx
- SQ Detector 2
- Xevo TQD
- Xevo TQ-S
- Xevo TQ-S micro
- Xevo TQ-XS
- Xevo G2-S
- Xevo G2-XS
PROCEDURE
- Refer to the mass spectrometer's operator's guide for how to install the APCI probe/source (for APCI mode) and corona pin.
By default, the pin is around 3 mm above the cone orifice and in a distance at around 7 mm.
- Increase the probe temperature stepwise up to 600 °C and tune the desolvation gas flow for sensitivity (low flow of 200 L/h might be sufficient).
Note: Especially when using the Probe heater for the first time, it's important to heat up slowly and stepwise. The probe heater might break otherwise. - Switch the divert valve to combined and start infusing the sample with the sample syringe simultaneously with the LC flow (e.g. 0.5 mL/min).
- Mark the probe position so that it is easy to return to the original position for ESI mode.
- Using the silver caliper, adjust the probe angle position for best sensitivity. This will probably be close to halfway between the cone and the corona pin.
- Switch to current control and adjust the corona pin current setting for the best sensitivity (usually 2-5 µA).
ADDITIONAL INFORMATION
Note: When voltage mode is applied, glow discharge and instable voltage is observed at around 1.3 kV Corona Voltage. Avoid voltages that leads to instable an readback due to voltage discharge.