Conductive polymer spray ionization

This is an advancement of paper spray ionization selective for hydrophilic compounds. Traditionally, paper spray utilizes cellulose as matrix. Since cellulose is hygroscopic it acts absorbing to many hydrophilic compounds and causes diffusion of the compound of interest. To overcome this and gain more sensitivity for this particular compound class an polymeric surface made of PMMA (polymethylmethacrylate) commonly known under the brand "plexiglass", had been used by the authors. The hydrophobic polymer does not interact with hydrophilic compounds, decreases diffusion, enhances microdroplett formation and therefore increases sensitivity for peptides or sugars up 100-fold compared to conventional paper spray ionization. 

Source: https://pubs.acs.org/doi/full/10.1021/acs.analchem.8b03460