303 results about "Ionization mass spectrometry" patented technology

The present invention provides a mass spectrometer having an ion lens capable of transporting an ion having a large mass to charge ratio with a high level of ion-passing efficiency even under a low-vacuum atmosphere. In conventional atmospheric pressure ionization mass spectrometers or similar mass spectrometers, applying an excessively high voltage to the ion lens undesirably causes an electric discharge. Therefore, the passing efficiency for an ion having a large mass to charge ratio cannot be adequately improved, which leads to a poor detection sensitivity. To solve this problem, the mass spectrometer according to the present invention includes a voltage controller 21 that controls a variable radiofrequency (RF) voltage generator 24 so that both the amplitude and the frequency of the RF voltage applied to the lens electrodes of an ion lens 5 are changed according to the mass to charge ratio of an ion to be analyzed. This control enables the ion lens 5 to focus an ion and transport it to the subsequent stage with a high level of passing efficiency even in the case of analyzing an ion having a large mass to charge ratio. Thus, the detection sensitivity is improved. The aforementioned control is conducted on the basis of the control data stored in a voltage control data storage 22. These data are obtained in advance by a measurement of a sample containing a substance having a known mass to charge ratio, in which the intensity of the signal of an ion detector is maintained while the analysis conditions are changed.

The present invention provides methods for obtaining information of a plurality of target molecules by matrix free LDI MS. Mass tagged complexes for detection of target molecules comprise a target molecule binding domain, and a mass tag separated by a cleavable linker. Methods of the invention may be used for example to analyze the distribution of a multiple target molecules in a complex sample, such as a tissue section.

A method of enhanced speciation of both positive and negatives species in an analyte is disclosed. The method can include producing a first analyte solution comprising an analyte composition and an effective amount of silver triflate, and analyzing the first analyte solution with an electrospray ionization mass spectrometer. The method can also include producing a second analyte solution comprising a portion of the analyte composition and an effective amount of a compound of formula I, and analyzing the second analyte solution with an electrospray ionization mass spectrometer. The compound of formula I is [NX⁺][OH⁻], where X is a linear, branched, or cyclic C₁-C₁₀ alkane; an aryl; a heterocyclic aromatic; or a heterocyclic moiety.

The invention relates to a novel IR laser desorption/vacuum UV single-photon ionization mass spectrum analyzing device for analysis and detection of a biological sample, which solves the problems of the prior art that uses matrix and is unlikely to analyze complex mixture with low polarity and low molecular weight. The device is structurally characterized in that a photoionization chamber is arranged on one side of a time-of-flight mass spectrometer, an ion injection hole is provided on one sidewall of the photoionization chamber, an ion injector and a sample target are arranged in the chamber, a laser is disposed outside the photoionization chamber on the sample target side, and vacuum UV light source is arranged on the other side. By combining IR laser desorption technology and vacuum UV ionization mass spectrum technology, the invention can achieve high-efficiency and rapid analysis without selecting different matrixes according to the sample and without complex pre-treatment and separation of the sample, thus preventing the matrix interference on mass spectral signals. The invention is specifically suitable for analysis of thermal-unstable and nonvolatile organic compounds and biological molecules.

A method for directly analyzing a lung cancer tissue sample based on the tissue electro-spray ionization mass spectrometry concretely comprises the steps that an electro-spray extraction ionization source in the tissue sample is set up; an extraction agent, namely, methyl alcohol is sucked through a micro-syringe connected with a quartz capillary, the extraction agent is dripped on the surface of the sample through the quartz capillary, and an injection pump controls the micro-syringe; the lung cancer tissue sample is cut into a piece of which the volume is 1 mm3 and placed at the tip of an acupuncture needle, and the needle tip is inserted into the sample and keep unexposed; the distance between the front end of the sample and an inlet of a mass spectrometer is adjusted, and the tail end of the acupuncture needle, the front end of the sample and the inlet of the mass spectrometer are adjusted to be in a horizontal coaxial state; DC voltage is applied on the acupuncture needle, so that extraction, desorption and ionization happen on the sample, and the sample generates spray which enters the mass spectrometer. According to the method, the information of molecules in the sample can be directly and quickly obtained, and the result shows that the method is a mass spectrometry method which has the advantages that the device is simple, manufacturing cost is low, ionization efficiency is high, and damage to the sample is small.

The invention discloses a capillary needle. The capillary needle comprises a tube body, the two ends of the tube body are respectively provided with an inlet and an outlet for electro-spray, a part of the tube body is bent to form a sampling end, and the sampling end is provided with a sampling port communicating with a cavity in the tube body. The invention also discloses an electro-spray ionization mass spectrometry analytical apparatus applying the capillary needle. The invention also simultaneously discloses a method applying the electro-spray ionization mass spectrometry analytical apparatus for analytical detection. The analytical apparatus is high in integration, compact in structure, easy to control, small in size and low in cost; the sample consumption is greatly reduced, and the experiment cost is decreased; an integrated sample introduction method is employed, and an sample introduction end does not have to be repeatedly placed in a sample and blank solution, such that cross contamination is reduced, and more importantly, the analytical flux is substantially improved; and through combination with an automatic sample changing system, different samples can be automatically introduced, and therefore, the capillary needle, the apparatus and the method are quite suitable for such fields as high-flux screening, unicell analysis, mass spectrum imaging analysis and the like.

A method for determination of at least one of the lipid species in a biological sample comprising subjecting the sample to lipid extraction to obtain a lipid extract and subjecting the resulting lipid extract to multidimensional electrospray ionization mass spectrometry using either precursor ion or neutral loss scanning (or both) of all naturally occurring aliphatic chains, lipid fragments and precursor ions leading to observed fragments to generate a multidimensional matrix whose contour densities provides structural and quantitative information directly without chromatography. A method for determination of lipid content and/or lipid molecular species composition and quantity directly from lipid extracts of a biological sample comprising subjecting said lipid extract to electrospray ionization multidimensional mass spectrometry by comparisons to standards and algorithms described herein.

Prior work on differential mobility analysis (DMA) combined with mass spectrometry (MS) has shown how to couple the output of the DMA with the inlet of an atmospheric pressure ionization mass spectrometer (APCI-MS). However, the conventional ion inlet to an APCI-MS is a round orifice, while conventional DMA geometries make use of elongated slits. The coupling of two systems with such different symmetries limits considerably the resolutions attainable by the DMA in a DMA-MS combination below the value of the DMA alone. The purpose of this invention is to overcome this limitation in the case of a parallel plate DMA. One solution involves use of an elongated rather than a circular MS sampling hole, with the long dimension of the MS inlet hole aligned with that of the DMA slit. Another involves use of a more elongated orifice in the DMA exit and a more circular hole on the MS inlet, the two being connected either through a short transfer conduit or through an ion guide. The DMAs described can also be coupled profitably to detectors and analyzers other than mass spectrometers.

The ionization chamber consists of a plurality of ports to accept multiple identical devices or varying devices. Ports may be arranged at various positions on the ionization chamber and at various angles with respect to the sampling orifice leading into the vacuum chamber of the mass spectrometer. A plurality of sprayers may operate in a time modulated manner and thereby the simultaneous multiplexed analysis of a multitude of samples is facilitated.

Laser desorption/ionization time-of-flight mass spectrometer (“LDI-TOF-MS”) devices, and methods, that accurately measure the mass of analytes contained in a sample and which also measure the quantities of analytes present in a sample in a consistent manner from instrument-to-instrument and over time on a single instrument. In particular, the invention provides LDI-TOF-MS devices and methods in which: 1) the energy of the laser pulse and the area of the sample illuminated (fluence) is consistent and controlled so as to produce consistent conditions for analyte desorption and ionization; 2) the mass analyzer behaves in a reproducible manner; and 3) the detection system produces a signal that consistently represents the arrival of ions of different masses.

There is disclosed an apparatus for providing an ionized analyte for mass analysis by photon desorption comprising at least one layer for contacting an analyte, and a substrate on which said layer is deposited. Upon irradiation of said apparatus, said analyte desorbs and ionizes for analysis by mass spectrometry. The layer or layers of said apparatus comprise a continuous film, a discontinuous film or any combinations thereof.

Electro-wettable sample presentation devices are useful in performing analytical measurements such as the detection of analytes contained within a liquid sample drop. The device comprises a virtual microwell for receiving a liquid sample drop; one or more intermediary electro-wettable sites at least one of which is contiguous to the microwell; and a terminal electro-wettable site which confines the deposition of analytes and matrix to within a predetermined area. The microwell is either an electro-wettable zone or a chemically-modified zone which exhibits either hydrophobic and non-adsorptive properties with respect to analytes, or hydrophobic and adsorptive properties with respect to analytes. Each of the electro-wettable sites modifies the surface of the sample presentation device between hydrophobic and hydrophilic states in response to an electrical potential applied between a liquid sample drop and the electro-wettable site so as to direct the positioning of the liquid sample drop.

The utility model relates to a normal pressure chemical extraction ionization source, equipped with an ionization pipe and a sample pipe. The ionization pipe and the sample pipe are aslant arranged within an included angle and a distance, and the ports of the ionization pipe and the sample pipe point an ionization area jointly. The sample pipe comprises a sample inlet pipe and a sample carrying gas pipe, a gas or liquid sample is guided in the sample inlet pipe or the sample inlet pipe is communicated with a sample eduction pipe of a neutral desorbing device. The method of utilizing the normal pressure chemical extraction ionization source of the utility model comprises the steps of using a sample flow educed from the sample pipe and an ion flow educed from the ionization pipe to impact with each other to occur the extraction ionization, and then carrying out a mass spectrometry. The normal pressure chemical extraction ionization source is especially suitable for the real-time rapid analysis of complicated samples, such as biological sample, food, drugs, environmental sample, etc.

The present invention is a method to determine the TAN and TAN as a function of boiling point for a hydrocarbon feedstream using an electrospray ionization mass spectrometer (ESI-MS). The steps of the method include determining the signal as a function of mass from the ESI-MS while minimizing the formation of oligomers and fragmentation of the molecular species in the feedstream and then determining the TAN from the signals. The TAN is also determined as a function of boiling point.

Prior work on differential mobility analysis (DMA) combined with mass spectrometry (MS) has shown how to couple the output of a planar DMA with the atmospheric pressure inlet of an atmospheric pressure ionization mass spectrometer (APCI-MS). However, because the ion inlet to APCI-MS instruments is a round orifice, while conventional DMA geometries make use of elongated slits, the coupling of both has attained less resolving power or tolerated a smaller sample flow rate than a DMA alone. The present invention overcomes these limitations with an axial DMA of cylindrical symmetry using more than two electrodes. The configuration is related to that previously proposed by Labowsky and Fernández de la. Mora (2004, 2006), where ions with a critical electrical mobility are brought into the symmetry axis of the DMA. Ions with this critical mobility are now optimally transmitted into the MS, with much higher resolution than possible in planar DMAs. In a preferred embodiment of this DMA facilitating DMA-MS coupling, one DMA electrode intersecting the symmetry axis is relatively planar.

A method and apparatus for probing the chemistry of a single droplet are provided. The technique uses a variation of the field-induced droplet ionization (FIDI) method, in which isolated droplets undergo heterogeneous reactions between solution phase analytes and gas-phase species. Following a specified reaction time, the application of a high electric field induces FIDI in the droplet, generating fine jets of highly charged progeny droplets that can then be characterized. Sampling over a range of delay times following exposure of the droplet to gas phase reactants, the spectra yield the temporal variation of reactant and product concentrations. Following the initial mass spectrometry studies, we developed an experiment to explore the parameter space associated with FIDI in an attempt to better understand and control the technique. In an alternative embodiment of the invention switched electric fields are integrated with the technique to allow for time-resolved studies of the droplet distortion, jetting, and charged progeny droplet formation associated with FIDI.

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. In another aspect of the invention, the levitated particle(s) may be controllably and precisely deposited onto a plate for subsequent analysis by matrix assisted laser desorption and ionization mass spectrometry.