Abstract: A method and apparatus for producing a discrete particle for subsequent analysis (such as mass spectrometry) or manipulation is disclosed. A discrete particle is generated by a particle generator. A net charge is induced onto the particle by an induction electrode. The particle is delivered to a levitation device where it is then electrodynamically levitated. If the particle is a droplet, desolvation will occur, leading to Coloumbic fissioning of the droplet into smaller droplets. The movement of the levitated droplet(s) can be manipulated by an electrode assembly. The droplet(s), and the charge thereon, can be delivered to a mass spectrometer in one aspect of the invention, providing an ion source for mass spectrometry without the detrimental space charge effects of electrospray ionization techniques.

Abstract: This application relates to a process for controllably placing two or more microspots on a target substrate in close proximity to one another. The microspots may then be simultaneously irradiated and the resulting ions detected by mass spectrometry, such as time of flight mass spectrometry. In one embodiment the size and spacing of the microspots on the substrate may be controlled by using an electrodynamic balance during the deposition step. The deposition procedure ensures that at least some of the microspots are spaced-apart on the substrate a distance less than the focused output of a single laser. Simultaneous irradiation of the adjacent microspots may cause desorption plumes of the microspots to interact in a gas phase, such as by ion-molecule reactions. The microspots may be configured to improve the ionization yield of the sample material in the gas phase and/or to increase the frequency of ion-molecule collisions in the gas phase.

Abstract: This application relates to a method and apparatus for coupling an analyte supply, such as a biomolecule separator, to an electrodynamic droplet processor. In one embodiment the biomolecule separator is a capillary liquid chromatography column and the droplet processor includes an droplet generator and an electrodynamic balance. The biomolecule separator and the droplet processor may be fluidly coupled to provide a continuous supply of analyte for analysis. The droplets may be controllably ejected from the electrodynamic balance and deposited on a target substrate for use in detecting the analyte by mass spectrometry, such as MALDI time of flight mass spectrometry. Prior to deposition, each of the droplets is levitated in the electrodynamic balance for a period sufficient to enable evaporation of volatile solvents present in the droplet solution, thereby increasing the analyte concentration in the droplet. The solution may include a MALDI liquid matrix and the target substrate may be a MALDI plate.

Abstract: A method and apparatus for producing a discrete particle for subsequent analysis (such as mass spectrometry) or manipulation is disclosed. A discrete particle is generated by a particle generator. A net charge is induced onto the particle by an induction electrode. The particle is delivered to a levitation device where it is then electrodynamically levitated. If the particle is a droplet, desolvation will occur, leading to Coloumbic fissioning of the droplet into smaller droplets. The movement of the levitated droplet(s) can be manipulated by an electrode assembly. The droplet(s), and the charge thereon, can be delivered to a mass spectrometer in one aspect of the invention, providing an ion source for mass spectrometry without the detrimental space charge effects of electrospray ionization techniques.