Waters GCT Premier MS with Agilent 6890N GC and 7683B Liquid Autosampler

The GCT Premier is a high-performance, bench-top, orthogonal acceleration/time-of-flight (oa-TOF) mass spectrometer. To identify volatile sample components, the instrument is coupled to a GC. To identify nonvolatile components, it operates as a standalone instrument that receives sample through a direct insertion (DI) or direct chemical ionization (DCI) probe. Unlike scanning instruments, a TOF instrument performs parallel detection of all masses within the spectrum at high sensitivity and acquisition rates. This is particularly advantageous when the instrument is coupled to fast chromatography, because each spectrum represents the sample composition Ion source 1-3 at a given moment, regardless of how rapidly the sample composition is changing.

Mass range

4000 Dalton.

Resolution

7000 resolution (FWHM) at m/z 614.

Acquisition rate

Up to 20 full spectra (to m/z 800) per second in normal mode.

Up to 10 full spectra (to m/z 800) per second in DRE extended mode.

GC sensitivity

EI positive ionization mode

1 pg of hexachlorobenzene (m/z 283.8) will give a peak to peak signal-to-noise ratio (S:N) >10:1 while acquiring full spectra over a mass range up to m/z 800.

CI positive ionization mode

100 pg of benzophenone (m/z 183.1) will give a S:N >150:1 while acquiring full spectra over a mass range up to m/z 800.

CI negative ionization mode

1 pg of octafluoronapthalene (m/z 272.0) will give a S:N >100:1 while acquiring full spectra over a mass range up to m/z 800.

Mass accuracy

When a suitable peak of known mass is used as an internal reference, the RMS error between the measured and calculated mass is less than 1 mDa for measurements below m/z 200, and is less than 5 ppm for measurements above m/z 200. Peaks are required to have sufficient intensity and be free from interference from other masses.

For example:

In EI positive ionization mode, less than 10 ng of methyl stearate (m/z 298.3) injected onto a capillary column will give, for all peaks above mass 70 and greater than 10% of the base peak intensity, 1.25 mDa RMS error or better, with the 4.0 GHz TDC.

Dynamic range

Enabled by dynamic range enhancement (DRE) and digital dead time

correction (DDTC), the dynamic range of the instrument is over four orders of

magnitude.