Abstract: A laser desorption ionization instrument for measuring the molecular weight of large organic molecules includes a time of flight (TOF) mass spectrometer. The time of flight mass spectrometer includes a sample lock for holding, under vacuum, a plurality of samples to be analyzed. A sample may be inserted into and removed from the sample lock and into the mass spectrometer without breaking vacuum in the spectrometer. Signal processing electronics of the LDIM instrument include means for identifying quasi-molecular species of a molecule being measured. The instrument includes improvements in ion optics, microchannel plate detectors, laser irradiation of samples, and preparation of samples for measurement.

Abstract: A laser desorption ionization instrument for measuring the molecular weight of large organic molecules includes a time of flight (TOF) mass spectrometer. The time of flight mass spectrometer includes a sample lock for holding, under vacuum, a plurality of samples to be analyzed. A sample may be inserted into and removed from the sample lock and into the mass spectrometer without breaking vacuum in the spectrometer. Signal processing electronics of the LDIM instrument include means for identifying quasi-molecular species of a molecule being measured. The instrument includes improvements in ion optics, microchannel plate detectors, laser irradiation of samples, and preparation of samples for measurement.

Abstract: An electrophoresis instrument includes a capillary tube mounted in an air cooled cartridge. The cartridge also supports a spherical lens which is part of the optical detection apparatus. The cartridge rests in a manifold which includes the sample and buffer reservoirs. The temperature of the capillary tube is controlled by measuring the electrical resistance of the capillary tube during the electrophoresis process and then cooling or heating the cartridge by circulating temperature controlled air over the tube. The optical path associated with the instrument is a fiber optic bundle bifurcated close to dual detectors into a reference arm and a sample arm so as to provide similar reference and sample optical paths. The instrument may be used for temperature control for gradient electrophoresis and also, a neutral marker for determining electro-osmotic flow may be detected.

Abstract: An electrophoresis instrument includes a capillary tube mounted in an air cooled cartridge. The cartridge also supports a spherical lens which is part of the optical detection apparatus. The cartridge rests in a manifold which includes the sample and buffer reservoirs. The temperature of the capillary tube is controlled by measuring the electrical resistance of the capillary tube during the electrophoresis process and then cooling or heating the cartridge by circulating temperature controlled air over the tube. The optical path associated with the instrument is a fiber optic bundle bifurcated close to dual detectors into a reference arm and a sample arm so as to provide similar reference and sample optical paths. The instrument may be used for controlling temperature in gradient electrophoresis and detecting neutral markers in determining electro-osmotic flow.