Abstract: A heated DESI spray device provides improved resolution or control of analyte desorption at a target locus on a sample. Heating controls spot size and enhances resolution in an imaging mode without impairing signal level. Additionally or alternatively the heated DESI spray may control desorption kinetics of a target analyte or otherwise control analyte discrimination in detection mode. One embodiment of the DESI spray is heated by heating nebulizing gas that accompanies the electrosprayed solvent. Another embodiment heats a separate gas stream that transports or directs desorbed material to the ion aperture of an analysis instrument. Heating may reduce size of primary droplets, alter the impact dynamics or the energy delivered by the spray to the surface, reduce size of secondary droplets and/or assure desolvation, improve species selectivity or otherwise affect sampling and enhance the ion signal level.

Abstract: A desorption atmospheric pressure chemical ionization (DAPCI) system delivers a primary ion beam composed of an inert, high velocity gas and solvent ions to a surface to effect desorption and ionization of both volatile and non-volatile species present on surfaces. A electrode having a tapered tip is connected to a high voltage power supply. The tapered tip projects outward from a capillary carrying a high-speed flow of gas. A vapor of a solvent is mixed into the annular gas flow surrounding the needle. The gaseous solvent vapor is ionized in close proximity to the tapered tip by virtue of the high voltage applied to the electrode. The high-speed flow of gas and solvent vapor ions extending outward from the capillary is directed toward a substrate on which an analyte of interest may have been deposited.

Abstract: A heated DESI spray device provides improved resolution or control of analyte desorption at a target locus on a sample. Heating controls spot size and enhances resolution in an imaging mode without impairing signal level. Additionally or alternatively the heated DESI spray may control desorption kinetics of a target analyte or otherwise control analyte discrimination in detection mode. One embodiment of the DESI spray is heated by heating nebulizing gas that accompanies the electrosprayed solvent. Another embodiment heats a separate gas stream that transports or directs desorbed material to the ion aperture of an analysis instrument. Heating may reduce size of primary droplets, alter the impact dynamics or the energy delivered by the spray to the surface, reduce size of secondary droplets and/or assure desolvation, improve species selectivity or otherwise affect sampling and enhance the ion signal level.

Abstract: A desorption atmospheric pressure chemical ionization (DAPCI) system delivers a primary ion beam composed of an inert, high velocity gas and solvent ions to a surface to effect desorption and ionization of both volatile and non-volatile species present on surfaces. A electrode having a tapered tip is connected to a high voltage power supply. The tapered tip projects outward from a capillary carrying a high-speed flow of gas. A vapor of a solvent is mixed into the annular gas flow surrounding the needle. The gaseous solvent vapor is ionized in close proximity to the tapered tip by virtue of the high voltage applied to the electrode. The high-speed flow of gas and solvent vapor ions extending outward from the capillary is directed toward a substrate on which an analyte of interest may have been deposited.

Abstract: A desorption atmospheric pressure chemical ionization (DAPCI) system delivers a primary ion beam composed of an inert, high velocity gas and solvent ions to a surface to effect desorption and ionization of both volatile and non-volatile species present on surfaces. A electrode having a tapered tip is connected to a high voltage power supply. The tapered tip projects outward from a capillary carrying a high-speed flow of gas. A vapor of a solvent is mixed into the annular gas flow surrounding the needle. The gaseous solvent vapor is ionized in close proximity to the tapered tip by virtue of the high voltage applied to the electrode. The high-speed flow of gas and solvent vapor ions extending outward from the capillary is directed toward a substrate on which an analyte of interest may have been deposited.