383 results about "Desorption ionization" patented technology

The present invention provides methods for identifying various biological states. Methods for diagnosis of diseases, in particular cardiovascular and brain diseases, are provided herein. One aspect of the invention is the analysis of lipoprotein complexes with summary survey scan mass spectrum for the analysis of biological states. Another aspect of the invention is the use of matrix assisted laser desorption ionization (MALDI) mass spectrometer to analysis lipoprotein complexes for the diagnosis of cardiovascular and brain diseases. Yet another aspect of the invention is a method of diagnosis of brain diseases by evaluating the characteristics of lipoprotein complexes.

Improvements have been made for collecting, focusing, and directing of ions and/or charged particles generated at atmospheric or near atmospheric pressure sources, such as but not limited to, electrospray; atmospheric pressure discharge ionization, chemical ionization, photoionization, and matrix assisted laser desorption ionization; and inductively coupled plasma ionization. A multiple-aperture laminated structure is place at the interface of two pressure regions. Electric fields geometries and strengths across the laminated structure and diameters of the apertures; all of which act to optimize the transfer of the ions from the higher pressure region into the lower pressure region while reducing the gas-load on the lower pressure region. Embodiments of this invention are methods and devices for improving sensitivity of mass spectrometry when coupled to atmospheric, near atmospheric, or higher pressure ionization sources by reducing the gas-load on the vacuum system.

A thin laminated high transmission electro-optical lens populated with a plurality of apertures in communication with its laminates used to improve the collection, focusing, and selection of ions generated from atmospheric pressure sources, such as electrospray, atmospheric pressure chemical ionization, inductively coupled plasma, discharge, photoionization and atmospheric pressure matrix assisted laser desorption ionization. The laminated lens is made of alternating layers of electrically insulating and metal laminates. The geometry of the lens may be planar or shaped into various curve shapes, any of which act to optimize both the direct current (DC) and alternate current (AC) electric field geometries and strengths across the lens for transferring virtually all the ions from the ion source into an ion-focusing region adjacent and upstream of a high pressure or atmospheric pressure interface to a mass spectrometer, ion mobility analyzer, or combination thereof. Embodiments of this invention are methods and devices for improving sensitivity of mass spectrometry when coupled to high pressure or atmospheric pressure ionization sources.

The invention relates to a method of using high mass matrix assisted laser desorption-ionization (MALDI) mass spectrometry for the qualitative and quantitative analysis of the effect of drug candidates on protein complexes such as protein-protein interactions in purified samples or complex biological matrices, as well as to the use of this method for lead compound optimization, drug characterization, drug manufacturing processes, and drug quality control processes, including automated high throughput applications.

A new ionization source named Surface Activated Chemical Ionization (SACI) has been discovered and used to improve the sensitivity of the mass spectrometer. According to this invention the ionization chamber of a mass spectrometer is heated and contains a physical new surface to improve the ionization process. The analyte neutral molecules that are present in gas phase are ionized on this surface. The surface can be made of various materials and may also chemically modified so to bind different molecules. This new ionization source is able to generate ions with high molecular weight and low charge, an essential new key feature of the invention so to improve sensitivity and reduce noise. The new device can be especially used for the analysis of proteins, peptides and other macromolecules. The new invention overcomes some of the well known and critical limitations of the Electrospray (ESI) and Matrix Assisted Laser Desorption Ionization (MALDI) mass spectrometric techniques.

An apparatus and method for generating analyte ions from a sample. An ion generating device is provided having a chamber with an outlet and a surface having a material and means for applying a high velocity gas flow through the chamber toward the outlet such that charged particles are produced by physical interaction between the high velocity gas and the material. The charged particles then induce the generation of primary ions by interaction with molecules of the high velocity gas. The primary ions are emitted from the outlet of the ion generating device toward a sample-bearing surface and analyte ions are generated by impact of the primary ions on the analyte sample on the surface.

Improvements have been made for collection and focusing of ions generated from atmospheric pressure sources such as electrospray, atmospheric pressure chemical ionization, inductively coupled plasma, discharge, photoionization and atmospheric pressure matrix assisted laser desorption ionization. A high transmission electro-optical surface is placed between the source regions and the focusing regions to optimize the field geometries and strengths in each respective region. Compression ratios of greater than 5000 are capable of transferring virtually all ions from large volume dispersive ion regions into ion beam cross-sections of less than 1 mm. Embodiments of this invention are methods and devices for improving sensitivity of mass spectrometry when coupled to atmospheric pressure ionization sources.

The present invention is directed to a method and device to desorb an analyte using heat to allow desorption of the analyte molecules, where the desorbed analyte molecules are ionized with ambient temperature ionizing species. In various embodiments of the invention a current is passed through a mesh upon which the analyte molecules are present. The current heats the mesh and results in desorption of the analyte molecules which then interact with gas phase metastable neutral molecules or atoms to form analyte ions characteristic of the analyte molecules.

The invention relates to method and apparatus for production of gaseous ions from components of a condensed phase sample and analysis thereof, wherein one or more liquid jet(s) is/are directed to the surface of the sample to be investigated, where the impact of the liquid jet on the sample surface produces droplets carrying sample particles which are turned into gaseous ions via the evaporation of liquid or, if desired, by a subsequent ionization after the evaporation and the obtained sample particles are analyzed by a known method.

The present invention discloses a graphene matrix and an application of the graphene matrix in matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) detection. According to the present invention, in the MALDI-TOF-MS, the graphene is adopted as an assisted matrix, such that the analysis and the detection of the materials including from the small molecule compounds to the biological macromolecules can be efficiently and rapidly achieved; importantly the background interference of the molecular ion peak of the traditional organic matrix can be effectively eliminated so as to achieve the analysis and the detections of amino acids, lipid compounds, peptides, proteins, oligonucleotides, and other structural molecules; the MALDI-TOF-MS adopting the graphene as the matrix is the desorption ionization method, which does not require addition of any organic matrixes, such that the decomposition of the analyte can be avoided, and good reproducibility and high salt tolerance are provided; the efficient and rapid detection method is provided for the natural products and the biological metabolites; the method further can be used for the detection of the common biological macromolecules, and can be popularized and applied in all the MALDI-TOF mass spectrometry so as to achieve the deep application of the graphene.

The invention is directed to a method for detecting low concentrations of bacteria in liquid solution that may or may not be complex liquid solutions. In one embodiment, immunomagnetic separation (IMS) is used to separate target bacterium that may be in a liquid mixture from other constituents in the mixture. A low concentration of a bacteriophage for the target bacteria is subsequently used to infect target bacterial cells that have been captured using the IMS technique. If at least a certain concentration of target bacterium are present, the bacteriophage will multiply to a point that is detectable. Matrix assisted laser desorption ionization/time-of-flight-mass spectrometry (MALDI/TOF-MS) is then used to produce a mass spectrum that is analyzed to determine if one or more proteins associated with the bacteriophage are present, thereby indirectly indicating that target bacterium were present in the liquid mixture.

A mass spectrometer includes: an electrospray unit for forming liquid drops of an electrospray medium; a voltage supplying member disposed to allow the liquid drops to be laden with a plurality of charges for heading toward a receiving unit along a traveling path; a substrate having a sample surface for placement of a sample and an irradiated surface opposite to the sample surface; and a laser transmission mechanism for irradiating the irradiated surface. The substrate permits propagation of laser energy therethrough such that laser energy is passed on to at least one analyte in the sample via the substrate so that the analyte is desorbed to fly along a flying path intersecting the traveling path to enable occlusion of the analyte in the liquid drops. As a result of dwindling in size of the liquid drops, charges will pass on to the analyte to form a corresponding ionized analyte.

The invention provides methods for preparing a sample for matrix-assisted laser desorption ionization (MALDI). In general, the methods involve: binding analytes in a sample to capture agents that are bound to matrix that is present in a plurality of wells of a multi-well sample plate, washing any unbound analytes from the matrix, cleaving any bound analyte/capture agent complexes with a MALDI cleavage agent, and depositing the cleavage products on a multi-sample MALDI sample plate. Kits and other compositions are provided for performing the subject methods. The subject invention finds use in methods of simultaneously assessing the presence of several analytes in a single sample, and, as such, the invention finds use in a variety of different medical, research and proteomics applications.

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.

The invention discloses application for analyzing micromolecules with irradiating nanometer carbon spots serving as a matrix assisted laser desorption ionization (MALDI) matrix. The carbon spots serve as an analysis method of the MALDI matrix and are suitable to mass spectrum analysis for the micromolecules with the m/z between 150-1000. Suitable molecule types comprise amino acid, polypeptide, beta-exhilarant, fatty acid, polymer and the like. When the method is used for detecting the molecule with the m/z between 150-1000, background peaks hardly exist to produce background interference. The method can be effectively used in the fields of organic and biomass spectrometry, spectrometry imaging, protein spectroscopy, metabonomics, biomarker discovery, environment analysis and the like.

The invention discloses a detection method and a device for ion mobility spectrometry of excited state molecular collision surface desorption ionization, an excited state generator is arranged in front of an ion entrance of a mobility tube of the ion mobility spectrometry, a placement region of the samples to be measured is arranged between the excited state generator and the ion mobility spectrometry, which is exposed in the atmosphere directly, the excited state generator includes a discharge cavity, the front end of the interior of the discharge cavity is connected with a discharge part, the back end of the discharge part is equipped with an ion filter door and an exclusion electrode sequentially, the back end of the exclusion electrode is an outlet of the discharge cavity, and an ion introducing electrode is arranged in the mobility tube of the ion mobility spectrometry. The invention can work in the open atmospheric environment, the measured surface does not need the pretreatment, the invention can realize the desorption ionization and rapid detection in situ of the trace components on the surface of the object, the invention can not only be used for analysis and detection of the surface pesticide residues, but can also be applicable to the detection of the toxic and harmful dangerous goods on the surface of the object. The invention is characterized by rapid detection speed, high sensitivity, small volume of the device, easy operation and so on.