Method of improved paper based mass spectrometry and novel wick support structures

The disclosed invention relates to electrospray and more specifically to wick based electrospray of analytes. The disclosed invention provides a means for improved electrospray extraction of analytes using a capillarity based fluid delivery system. The disclosed invention employs a wire screen mesh sandwiching the substrate media, without impeding capillarity of a wetting solvent spray fluid applied to the substrate. A further benefit is that electrical contact can be made to the substrate. Yet another benefit is that the substrate and wire mesh can be further enclosed in a polymer or other insulating sleeve that is flat and very thin, the preferred form factor is very similar to that of a credit card.