Decide what ionization technique you want
To obtain a mass spectrum, the sample must first be ionized. The instruments in the Mass Spectrometry Laboratory are capable of all modern ionization techniques. The flow chart will help you decide which technique is best for your sample. Suppose, for example, you have a compound that is involatile, non-polar, and has a molecular weight of 500. The flow chart shows that electron usage impact (EI) would be a poor choice, since it requires that the sample be volatile. The best choice would be field desorption (FD). For a more detailed description of the applicability of the various ionization techniques see the ionization techniques section. You also will need to take into consideration the sample submissions guidelines. If you have trouble deciding on an ionization technique, you can ask either your group expert or the Mass Spectrometry Laboratory staff.
Flowchart of Mass Spec Techniques — Sample Submission Guidelines
