Abstract:
The invention concerns a time-of-flight mass spectrometer for the analysis of a large number of samples on a sample carrier using laser desorption and associated analytical procedures. The invention uses a special beam focusing system for the pulsed laser beam in a time-of-flight mass spectrometer to generate a firm pattern of focal points, inserts a pattern of samples on a sample carrier into the pattern of focal points, and focuses the ions generated in the laser focal points by an ion-optical imaging system onto one or more ion detectors in such a way that the samples in the focus pattern are measured simultaneously or quasi-simultaneously. The pattern of pulsed focal points can be created simultaneously through spatially splitting the beam, or by a temporal sequence of different deflections towards the firm locations of the pattern.
Abstract:
The invention relates to methods and instruments for measuring daughter-ion spectra (also known as fragment-ion spectra or MS/MS spectra) in time-of-flight mass spectrometers, especially of those with reflectors, with post acceleration of selected parent and daughter ions by raising the potential of a “potential lift” during the passage of the ions. The invention consists of a potential lift device which is equipped with a power supply for velocity spread focusing by delayed acceleration of the ions after lifting the potential, thus making it possible to produce a focus of the velocity spreads of ions at the detector. In addition, it is possible to facilitate the adjustment of the mass spectrometer by dynamically shaping the acceleration pulse of the lift device to focus the velocity spreads of all ion masses in the spectrum on the detector.
Abstract:
The invention relates to a method and a device which reduces the phase space volume of ions in an ion beam in such a way that their injection into a downstream time-of-flight mass spectrometer optimizes the performance of that spectrometer. The performance of the time-of-flight mass spectrometer, i.e. the sensitivity of the spectrometer, the temporal resolution for fast concentration changes of the examined substances, and particularly the mass resolving power, relates critically to the transmission of the ions. The invention consists of completely decelerating the ions by means of collisions with a damping gas in an RF ion guide system, guiding them to the end of the ion guide system by active forward thrust, extracting them by a drawing lens system, and forming an ion beam with a low phase space volume. In particular, the ion guide system can take the form of a pair of wires coiled in a double helix and be surrounded by an envelope which is filled with the damping gas.
Abstract:
The invention relates to devices and methods for the contamination-free transfer of biological specimens, for example from supply containers, into the microtiter plates or comparable processing devices used to process the specimens. Such contamination-free transfer systems for DNA samples are known for microtiter plates with 96 cavities; they are based on covers for the cavities which can be removed by pipetting robots. The invention consists in covering the processing volumes of the microtiter plates together by a slidable blind which has one or more openings that can be slid over the processing volumes and through which the specimens can be pipetted. The space under the foil is swept by clean gas which emerges from the openings in order to prevent contamination by aerosols.
Abstract:
The invention concerns instruments for fast, selective replication of deoxyribonucleic acid (DNA) from biomaterial through polymerase chain reaction (PCR), working in individual duplication thermocycles. The invention consists of extremely brief cycle times of only a few seconds for the PCR reactions, generated, on the one hand, by reaction chambers for the reception of the reaction solution constructed of a pattern of fine capillaries in close proximity to heating and cooling elements in order to optimally accelerate the temperature setting in the reaction solution for the three temperature phases of the PCR duplication cycles and, on the other hand, by keeping the flow rates in the capillaries to a minimum during the amplification phase so that the polymerase reaction is not disturbed. The capillary pattern can be simply produced by means of microsystem technology.
Abstract:
An ion trap is provided in which higher multipole field fractions can be switched on and off and, in addition, can be electrically tuned. Specifically, the electrodes of an ideally shaped ion trap are divided into rotationally symmetrical component electrodes positioned facing the interior of the ion trap on a hyperboloidal surface with rotationally symmetry.
Abstract:
The invention relates to an RF quadrupole ion trap mass spectrometer with ionization of the substance molecules outside the vacuum system.The invention consists of using only a single high-vacuum pump for generating the vacuum without any differential pump stages and generating the necessary pressure stages for operating the mass spectrometer by means of a sequence of openings with adjusted conductances. The necessarily very small inlet opening to the vacuum system is only able to transport very small quantities of ions of the analyzed substances in the gas stream. However, these quantities are adequate for operating the mass spectrometer because the ion trap used as mass spectrometer is capable of collecting and storing ions over relatively long periods of time.
Abstract:
The invention relates to methods and devices for the temporary storage of ions which are to be subjected to mass spectrometric analysis. Such temporary storage of ions in an RF multipole rod system for their analysis in an RF quadrupole ion trap is known from U.S. Pat. No. 5,179,278. The invention uses this known temporary storage for such ions which are produced in an ion source from substance peaks from chromatographic or electrophoretich separation devices, or from other devices which feed substances in form of short-lasting peaks. The temporary store thereby accepts sufficient ions of a substance peak for several successive mass spectrometric analyses, so that a mass spectrometric characterization of the substances, which may also require varying measurement methods, is made possible to the desired degree. Particularly ions from electrophoretically or chromatographically separated substance peaks should be able to be temporarily stored long enough until the mass spectrometric analyses have been concluded to the desired extent. Several temporary stores can collect the ions from several rapidly successive substance peaks. However, short-lasting substance peaks from laser desorptive or pyrolitic processes can also be thoroughly analyzed by means of temporary storage.
Abstract:
A method for rapid loading of large sample supports with a very large number of analyte samples for mass spectrometric analysis using the ionization method of matrix-assisted desorption by laser bombardment (MALDI). The method consists of using microtiter plates already introduced in biochemistry and molecular genetics for parallel processing of a large number of dissolved samples and a multiple pipette unit for simultaneous transfer of sample solution quantities from all reaction wells on a microtiter plate to the sample support, the sample support having at least the same size. By repeated loading with samples from other microtiter plates, spaced between the samples already applied, a very high density of samples can be achieved. Some of these samples can be reserved for a mass spectrometric determination of the sample positioning on the sample support, and the positions of the other samples can then be interpolated.
Abstract:
A method for measuring the mobility spectra of ions with ion mobility spectrometers (IMS). The method consists of impressing upon the essentially continuous ion flow of an IMS ion source, which comprises various ion types with various mobitities, a temporal switching signature with an ion admission of approximately 50% by using a very fast ion flow switch, whereby the signatures for the various ion types are displaced toward each other in different manners during the operating time due to the different velocities. From the quasi-continuously received ion current signal at the end of the path of the ion mobility spectrometer the composition of the ion types can be recovered according to mobility and intensity by decoding the switching signature. At the same time an improvement in resolution can be achieved by deconvolution of the diffusion profile. The method has a high duty cycle for the substance admitted and for the ions of ion flow.