| abstract |
A mass spectrometer with phonon sensitive cryogenic particle detector determines the masses of macromolecules, proteins, large peptides, long DNA-fragments and polymers. The kinetic energy of the electrostatically accelerated charged macromolecule is absorbed in the cryogenic particle detector thereby exciting phonons which are detected by phonon sensors. The macromolecules are detected in the single particle counting mode with a sensitivity independent of their respective masses. The mass spectrometer contains a single-channel cryogenic particle detector providing high sensitivity. The mass spectrometer contains a spatially resolving multi-channel cryogenic detector array providing both high sensitivity and high throughput. The mass spectrometer consists of a vacuum vessel in which is a magnet, a mass separator, a feed through and a phonon sensitive cryogenic detector array. The cryogenic detector array consists of an absorber and a specified number of phonon sensors. The mass separator is placed in the magnetic field of the magnet and the feed through, on electrical potential U1, but electrically insulated from the magnet. The cryogenic detector array is on electrical ground potential U2. The macromolecules are accelerated by the voltage difference U1-U2 and reach the cryogenic detector array with a kinetic energy proportional to U1-U2. The cryogenic detector array is cooled to its operating temperature T2 by being thermally mounted to a cold finger of the cryostat with bath temperature T2. The mass of the macromolecule is determined by the spatial and time information provided by the cryogenic detector array. |