Abstract: A solvent delivery subsystem for a chromatography device performs relatively low pressure, high flow mixing of solvents to form a gradient and subsequent high pressure, low flow delivery of the gradient to the separation column. The mixing of the gradient is independent and does not interfere with the gradient delivery. To form the gradient, the outputs of an aqueous pump and an organic pump are mixed to fill a storage capillary while a downstream point from the storage capillary is vented to atmosphere. After gradient formation, the vent to atmosphere is closed, the solvent delivery system rises to high pressure, and only the aqueous pump runs for gradient delivery. To maintain integrity of the fluid stream, the solvent delivery system uses feed forward compensation and controls at least one parameter selected from the group consisting of pressure and flow in the conduit means to follow a gradual ramp.

Abstract: A solvent delivery subsystem for a chromatography device performs relatively low pressure, high flow mixing of solvents to form a gradient and subsequent high pressure, low flow delivery of the gradient to the separation column. The mixing of the gradient is independent and does not interfere with the gradient delivery. To form the gradient, the outputs of an aqueous pump and an organic pump are mixed to fill a storage capillary while a downstream point from the storage capillary is vented to atmosphere. After gradient formation, the vent to atmosphere is closed, the solvent delivery system rises to high pressure, and only the aqueous pump runs for gradient delivery. To maintain integrity of the fluid stream, the solvent delivery system uses feed forward compensation and controls at least one parameter selected from the group consisting of pressure and flow in the conduit means to follow a gradual ramp.

Abstract: A solvent delivery subsystem for a chromatography device performs relatively low pressure, high flow mixing of solvents to form a gradient and subsequent high pressure, low flow delivery of the gradient to the separation column. The mixing of the gradient is independent and does not interfere with the gradient delivery. To form the gradient, the outputs of an aqueous pump and an organic pump are mixed to fill a storage capillary while a downstream point from the storage capillary is vented to atmosphere. After gradient formation, the vent to atmosphere is closed, the solvent delivery system rises to high pressure, and only the aqueous pump runs for gradient delivery. To maintain integrity of the fluid stream, the solvent delivery system uses feed forward compensation and controls at least one parameter selected from the group consisting of pressure and flow in the conduit means to follow a gradual ramp.

Abstract: The invention provides improved methods and apparatus for fluid chromatography, and is particularly appropriate to high-pressure liquid chromatography carried out using eluent flow rates less than 1 ?l/minute, for example on nanoflow columns. In both single- and multi-dimensional chromatography systems, especially those comprising trapping media to facilitate injection of relatively large volumes of sample on to nanoflow columns, the on-line addition of a diluting solvent enables stronger eluents and sample solvents to be employed without causing premature release of analytes from the trapping media or the degradation of the second dimension chromatographic separation. The invention may be advantageously used for two-dimension reverse phase/reverse phase separations, especially for the separation of complex mixtures of peptides.

Abstract: A method for making a fluid-processing apparatus involves mixing a colloidal suspension with a matrix material, applying the mixture to a surface of a conduit, and curing the applied mixture to provide a conductive coating. A fluid-processing apparatus includes a conduit and a conductive layer adjacent to a surface of the conduit. The conductive layer includes graphite particles embedded in a matrix. The fluid-processing apparatus supports, for example, electrospray-ionization for mass spectrometry, capillary electrophoresis, or capillary electro-chromatography.

Abstract: A method for making a fluid-processing apparatus involves mixing a colloidal suspension with a matrix material, applying the mixture to a surface of a conduit, and curing the applied mixture to provide a conductive coating. A fluid-processing apparatus includes a conduit and a conductive layer adjacent to a surface of the conduit. The conductive layer includes graphite particles embedded in a matrix. The fluid-processing apparatus supports, for example, electrospray-ionization for mass spectrometry, capillary electrophoresis, or capillary electro-chromatography.

Abstract: Disclosed herein is a sample preparation plate used to prepare a sample for mass spectrometry. In particular, a sample plate used to concentrate a sample as well as remove contaminants from the sample while providing easy manipulation of small liquid droplets on a surface with minimal sample loss.

Abstract: Embodiments of the present invention facilitate servicing or changing a discharge tube or modifying the position of a discharge tube with respect to a orifice of a detector and/or a nebulizing gas conduit. The apparatus features a discharge tube housing that slidably receives a discharge tube. A union coupling the discharge tube to a source of fluid is slidably mounted to a mounting assembly holding the tube housing.

Abstract: Featured are devices, methods and kits for preparation of samples of peptides and proteins from a solution; more particularly to such devices and methods in which carbon nanotubes are utilized for sample preparation and/or purification of peptide and/or protein samples from a solution. A sample to be treated/processed can comprise proteins, peptides or any other molecule having an amine moiety that can be protonated under low pH, such as, but not limited to, pH 5. Such a sample also can contain contaminants such as salts, detergents, etc. that will be eliminated during the sample preparation/purification process of the present invention. The methods, devices and kits of the present invention advantageously provide for the concentration of the sample, removal of contaminants and ease of manipulation of small liquids without the concomitant loss of sample.

Abstract: The invention provides improved methods and apparatus for fluid chromatography, and is particularly appropriate to high-pressure liquid chromatography carried out using eluent flow rates less than 1 ?l/minute, for example on nanoflow columns. In both single- and multi-dimensional chromatography systems, especially those comprising trapping media to facilitate injection of relatively large volumes of sample on to nanoflow columns, the on-line addition of a diluting solvent enables stronger eluents and sample solvents to be employed without causing premature release of analytes from the trapping media or the degradation of the second dimension chromatographic separation. The invention may be advantageously used for two-dimension reverse phase/reverse phase separations, especially for the separation of complex mixtures of peptides.

Abstract: A solvent delivery subsystem for a chromatography device performs relatively low pressure, high flow mixing of solvents to form a gradient and subsequent high pressure, low flow delivery of the gradient to the separation column. The mixing of the gradient is independent and does not interfere with the gradient delivery. To form the gradient, the outputs of an aqueous pump and an organic pump are mixed to fill a storage capillary while a downstream point from the storage capillary is vented to atmosphere. After gradient formation, the vent to atmosphere is closed, the solvent delivery system rises to high pressure, and only the aqueous pump runs for gradient delivery. To maintain integrity of the fluid stream, the solvent delivery system uses feed forward compensation and controls at least one parameter selected from the group consisting of pressure and flow in the conduit means to follow a gradual ramp.

Abstract: The present invention provides a device, system, and associated methods to actively or passively sample air by directing it onto the surface of a porous light-absorbing semiconductor, for example, a desorption/ionization on porous silicon (“DIOS”) chip. Upon adsorption of an analyte, the surface may be analyzed directly by laser desorption/ionization time-of-flight mass spectrometry. Because the process of laser desorption/ionization and subsequent mass detection does not require elevated temperatures, thermal degradation of analytes is avoided.

Abstract: Embodiments of the present invention facilitate servicing or changing a discharge tube or modifying the position of a discharge tube with respect to a orifice of a detector and/or a nebulizing gas conduit. The apparatus features a discharge tube housing that slidably receives a discharge tube. A union coupling the discharge tube to a source of fluid is slidably mounted to a mounting assembly holding the tube housing.

Abstract: Disclosed herein is a mass spectrometer having an atmospheric pressure photoionization (APPI) source that comprises a discharge lamp coupled to a nebulizer, wherein the nebulizer is at, or near, atmospheric pressure. The discharge lamp curves around the vapor path and this coaxial design offers significant advantages over the prior art such as increased photon flux resulting in increased photoionization efficiency. One of the significant benefits of an increase in photon flux is that absorption of the UV radiation by solvents such as acetonitrile is minimized. The APPI source described herein also facilitates a larger photoionization interaction zone with effluent from the nebulizer, which may be heated. Additionally, no dopant is required in this coaxial APPI system.

Abstract: Disclosed herein is a mass spectrometer having an atmospheric pressure photoionization (APPI) source that comprises a discharge lamp coupled to a nebulizer, wherein the nebulizer is at, or near, atmospheric pressure. The discharge lamp curves around the vapor path and this coaxial design offers significant advantages over the prior art such as increased photon flux resulting in increased photoionization efficiency. One of the significant benefits of an increase in photon flux is that absorption of the UV radiation by solvents such as acetonitrile is minimized. The APPI source described herein also facilitates a larger photoionization interaction zone with effluent from the nebulizer, which may be heated. Additionally, no dopant is required in this coaxial APPI system.

Abstract: A tandem mass spectrometer apparatus includes an ion source (29); a first mass spectrometer MS-1 having a magnetic sector (24) and an electric sector (21); and a second mass spectrometer MS-2 having a CID cell (13), an offset parabolic ion mirror (17) and an ion detector (18).

Abstract: Disclosed herein is a mass spectrometer having an atmospheric pressure photoionization (APPI) source that comprises a discharge lamp coupled to a nebulizer, wherein the nebulizer is at, or near, atmospheric pressure. The discharge lamp curves around the vapor path and this coaxial design offers significant advantages over the prior art such as increased photon flux resulting in increased photoionization efficiency. One of the significant benefits of an increase in photon flux is that absorption of the UV radiation by solvents such as acetonitrile is minimized. The APPI source described herein also facilitates a larger photoionization interaction zone with effluent from the nebulizer, which may be heated. Additionally, no dopant is required in this coaxial APPI system.