The Agilent 1100 Series LC/MSD quadrupole mass spectrometer features an automatic tuning program (Autotune) that performs this function without operator interaction. One of the essential functions within Autotune is gain checking and gain calibration. This note provides an overview of LC/MSD tuning and the Autotune function, and a more detailed look at gain calibration and adjustment within Autotune.
The document describes the tuning process for the Agilent 1100 Series LC/MSD, which optimizes sensitivity, resolution, and mass assignments. It details the Autotune program, an automated tool that adjusts parameters for ion transmission and detection without operator intervention, generating tune files for positive and negative ion modes.
A significant portion of the text focuses on gain calibration, explaining how the system checks and adjusts the electron multiplier voltage to ensure a gain setting of 1.0 produces the target signal abundance for mass 622. The note clarifies that gain calibration occurs during the positive-ion portion of the autotune routine and discusses the relationship between electron multiplier voltage and gain.
| Target abundance for gain calibration | mass 622 |
|---|---|
| Gain setting for positive ion autotune | 1.0 |
| Maximum electron multiplier voltage warning | 2600 volts |
| Recommended tuning frequency | monthly |
Gain calibration checking occurs only during the positive-ion portion of autotune.
The user is warned that system maintenance may be required.
Tuning is generally not needed more often than monthly.