Introduction
This page contains spectra that are representative of the normal level of performance of this instrument. A brief description of the acquisition protocol is given for each set of measurements. More detailed information about the proper instrument set-up and operational parameters necessary to reproduce these measurements can be found in the appropriate training manual or application note.
- Tuning and calibration - EI mode - METRI
- Calibration - EI mode - HEPTACOS
- Sensitivity - EI mode - benzophenone
- GC Testmix - EI mode
- Tuning and calibration - CI positive ion
- Sensitivity - CI positive ion
- Tuning and calibration - CI negative ion
- Sensitivity - CI negative ion
Tuning and Calibration - EI mode - METRI
Allow the instrument to warmup for at least fifteen minutes prior to tuning and calibration. Introduce approximately 1microliter of METRI into the reference inlet. On the GCT page, zoom in on m/z 285. Tune the instrument. Typical results are shown below:
Acquire and calibrate. Typical results are:
After calibration, and with m/z 285 lock mass enabled, typical METRI single scan data:
After calibration, and with m/z 285 lock mass enabled, typical METRI 10-scan averaged data:
Note that the single scan data is almost as accurate as the co-added data. This is generally true when the ion statistics are favorable. Where ion statistics are poor, co-added data will give better results.
| Mass (Theoretical | Mass (Measured) | Error (PPM) |
| 68.9952 | 68.9949 | 4 |
| 75.9998 | 75.9999 | -1 |
| 102.0030 | 102.0031 | -1 |
| 121.0014 | 121.0016 | -2 |
| 189.9966 | 189.9969 | -2 |
| 265.9964 | 265.9984 | -8 |
Calibration - EI mode - HEPTACOS
Tune with METRI as discussed above. Remove the METRI. Introduce one microliter of heptacosamine (HEPTA). Acquire data and calibrate.
Typical single-scan data of HEPTA:
Sensitivity - EI mode - benzophenone
The benzophenone test mixture concentration should be approximately 5.0 nanograms per microliter (5.0 ppm). One microliter is injected via the autosampler at a 50:1 split, resulting in approximately 100 picograms on the column. Data is acquired isothermal at 200 degrees C; 2 scans per second. Typical GC and MS results are shown below:
The standard GC test mixture has 8 constituents at approximate concentrations of 50 ppm per component. One microliter is injected via the autosampler at a 50:1 split, resulting in approximately 1 nanogram per component on the column. Data is acquired isothermal at 110 degrees C; 2 scans per second. Typical GC and MS results are shown below:
Tuning and calibration - CI positive ion