Answer 13.1

a) What is the novel feature of ambient mass spectrometry?

The novel feature of desorption electrospray ionization (DESI) is that it allows ambient MS without sample preparation or sample pre-treatment. Furthermore, “ambient” means here not only the mere operation at atmospheric pressure. In ambient MS, samples are accessible to observation and may even be subjected to some kind of processing, either mechanical manipulations or chemical treatments, while mass spectra are continuously being measured.

b) When were DESI and DART introduced?

Desorption electrospray ionization (DESI) was introduced at the end of 2004. Direct analysis in real time (DART) followed soon in early 2005.

c) Describe some uses of ambient MS techniques.

Ambient MS enables the detection of surface materials like waxes, alkaloids, flavors, or pesticides from plants as well as explosives, pharmaceuticals, or drugs of abuse from luggage or banknotes. These and many more analytical applications are readily accessible by exposing the corresponding items to the ionization region of the interface.

d) Collect some of the key characteristics usually stated when it comes to praise ambient MS. Are they always realized?

„Zero“ sample preparation: a sample needs just to be exposed to the ionizing medium under ambient conditions. Ambient MS is therefore fast, easy to be performed, ready for rapid screening and open access to MS analyses.
As always, one should carefully examine a method prior to large scale application. Ambient MS is generally limited to analysis of material exposed on surfaces.