Abstract: A novel electron multiplier that regulates in real time the gain of downstream dynodes as the instrument receives input signals is introduced. In particular, the methods, electron multiplier structures, and coupled control circuits of the present invention enable a resultant on the fly control signal to be generated upon receiving a predetermined threshold detection signal so as to enable the voltage regulation of one or more downstream dynodes near the output of the device. Accordingly, such a novel design, as presented herein, prevents the dynodes near the output of the instrument from being exposed to deleterious current pulses that can accelerate the aging process of the dynode structures that are essential to the device.

Abstract: A novel electron multiplier that regulates in real time the gain of downstream dynodes as the instrument receives input signals is introduced. In particular, the methods, electron multiplier structures, and coupled control circuits of the present invention enable a resultant on the fly control signal to be generated upon receiving a predetermined threshold detection signal so as to enable the voltage regulation of one or more downstream dynodes near the output of the device. Accordingly, such a novel design, as presented herein, prevents the dynodes near the output of the instrument from being exposed to deleterious current pulses that can accelerate the aging process of the dynode structures that are essential to the device.

Abstract: A MALDI/LDI source includes an ion collection device, e.g., a skimmer, orifice, mass analyzer, ion transfer optics and/or ion guide, configured for use with a short focal length lens with a large aperture. In some embodiments, the ion collection device includes an outer edge that can be disposed approximately parallel to a beam envelope between a lens and a focal point positioned at a MALDI/LDI sample. This configuration of the outer edge allows the ion collection device to be placed in close proximity to the focal point. This placement results in favorable collection efficiencies of laser desorbed analyte from the MALDI/LDI sample.

Abstract: A MALDI mass spectrometer includes a radiation source, such as a gas or solid state laser, that emits a beam of radiation (typically in the UV or IR wavelengths) directed along the central axis of a linear ion trap in which analyte ions and matrix cluster ions are confined. The radiation beam has a wavelength that is strongly absorbed by the matrix cluster ions. The absorption of radiation by the matrix cluster ions produces dissociation of the matrix cluster ion into fragments having mass-to-charge ratios that lie below a mass-to-charge ratio range of interest. Thus, chemical noise associated with matrix cluster ions is reduced or eliminated.

Abstract: A three section linear or two-dimensional (2D) quadrupole ion trap as a high performance mass spectrometer is described. Mass analysis is performed by ejecting ions radically out slots formed in at least two of the rods using the mass selective instability mode of operation. The slot geometry is optimized to enable ions of different mass ranges to be scanned out of differently dimensioned slots. Multiple detectors arranged to receive ejected ions in multiple directions provide the ability to simultaneously or sequentially scan or perform mass analysis of ions of different natures.