Accurate mass determination by Mass Spectrometry

Principles

Compound masses can be measured with high resolution and high mass accuracy.

Sample

Samples should be of high purity. Any ionisable impurity may suppress ionisation of the compound of interest. Samples can be submitted as solids (recommended) or in solution using an appropriate solvent, an accurate amount and concentration of the sample must be provided. It is necessary that a low percentage of acid will be added to the sample prior to measurement.

Instrumentation

LTQ Orbitrap XL mass spectrometer accurate to within 1-5 ppm for most compounds and mass range m/z 200-4000.

Experiment

Sample introduction by ESI is performed by direct injection using a syringe pump.

Results

A written report is provided describing the analysis undertaken and masses measured (spectrum included). Comparisons with calculated masses are made. The report is sent by e-mail. Raw data are archived by ProFI. If the data are used as a part of a scientific publication, reference to ProFI Lab should be made in the acknowledgements.