Figure 3.

DESI experiments make use of a stream of charged solvent droplets generated from a solvent capillary flowing adjacent to a capillary containing nebulizing gas. The analyte is taken up by the charged solvent upon contact with the sample mounted on a non-conductive surface. Subsequent collisions with other charged droplets results in formation of multiply charged ions. These ions are taken up by the mass spectrometry inlet. NanoDESI experiments work similarly to DESI but use a fused capillary for both solvent and nebulizing gas. A second capillary that leads directly to the mass spectrometer inlet is placed near the sample, and a solvent is formed between the two capillaries.