Abstract: A method and apparatus for monitoring and controlling the nano-scale flow rate of fluid in the operating flow path of a HPLC system without relying on a nano-scale sensor in the operating flow path. A main flow sensor is disposed in the main flow path between the pump and a flow-divider. A waste flow sensor is disposed in the waste flow path downstream of the splitter. The output signal of the waste flow sensor is subtracted from the output signal of the main flow sensor in a difference circuit. The difference signal is divided by the output signal from the main flow sensor in a divider circuit. The output of the divider circuit represents an empirical split ratio of the flow-divider and is independent of media composition.

Abstract: A method for supplying solvent to an ultra-high pressure liquid chromatography system using a hydraulic amplifier. The hydraulic amplifier system includes a hydraulic cylinder comprising a primary piston chamber in which a primary piston is disposed and a secondary piston chamber in which a secondary piston is disposed. The cross-sectional area of the primary piston is larger than the cross-sectional area of the secondary piston. The difference in the cross-sectional areas of the pistons creates an amplification of the pressure in the primary piston chamber and a reduction in flow rate.

Abstract: The present invention provides devices and methods for controlling the flow of fluids in very high pressure situations. The devices feature valve shafts having bearings and pins to hold stator surfaces and rotor surfaces in proper alignment.

Abstract: Embodiments of the present invention feature a method and apparatus for detecting defects, such as, leaks, component failure and adverse performance. One embodiment of the present apparatus for pumping fluid comprises a pumping chamber having an inlet and an outlet powered by a motor. The motor operates in pumping mode upon receiving a pumping signal. The apparatus further comprises at least one inlet valve in fluid communication with the inlet of the pumping chamber. And, the apparatus comprises a switchable valve in fluid communication with the outlet of the pumping chamber. The switchable valve has a closed position and an open position, and assumes the closed position upon receiving a close signal. A pressure measuring device is in fluid communication with the pumping chamber, between said inlet valve and switchable valve. The pressure measuring device determines a minimal pressure and first threshold pressure at a first time and a second threshold pressure at a second time.

Abstract: Disclosed herein is a device for holding a substrate having one or more samples in a position for ionizing the samples with a light energy source. The device has a receiving plate with a receiving surface, a back surface and an edge defining an outline. One or more receiving lips project from the receiving surface. The receiving surface receives the back face of the substrate with at least one edge received by the receiving lips for positioning the substrate for ionization of the sample. The device also has at least one substrate clip that has a front finger and a back finger for capturing and aligning the substrate. The front finger extends across the thickness of the receiving plate and substrate to engage the front edge of the substrate to hold the substrate in position. The back finger engages the back surface of the receiving plate. The receiving plate cooperates with the space in a matrix assisted laser desorption ionization mass spectrometer to hold the samples in position for ionization.

Abstract: A mass spectrometer is disclosed wherein the experimentally determined mass to charge ratios of ions are reported together with an error band for each mass to charge ratio determination. The error band may, for example, reflect a 95% probability or confidence that the real, true, actual or accepted mass to charge ratio of the ion lies within the error band. By accurately determining the error band the possible candidate ions in a database can be accurately restricted whilst also guarding against over restriction.

Abstract: A solid phase extraction (SPE) device having a reservoir with an opening; a well comprising an internally tapered wall, the well having a wider interior diameter at an end closest to the opening than at an exit spout; a first filter within the well; a bed of sorbent particles within the well below the first filter; and a second filter having a diameter smaller than the first filter within the well below the bed of sorbent particles and above the exit spout is provided. A method of performing SPE using the device is also provided.

Abstract: Mass intensity values, isotopic ratios and exact mass differences between isotopes may be obtained and analyzed to determine if there are one or more masses of interest. In one implementation, a method will look among the mass intensity values for peaks of interest. The mass intensity values, representative of isotopic signatures, will be compared to a criteria in order to determine which of the masses are of interest. Although the invention is not so limited, examples of such criteria include mass intensity values above a specified threshold, within a certain ratio of another mass intensity value, and/or separation between the masses themselves. Optionally, a tolerance may be applied to the criteria. If masses are found to be of interest, MS/MS can automatically be triggered for one or all of the masses of interest, when an analyzing system such as an LC-MS-MS, GC-MS-MS or MALDI-MS-MS system is used.

Abstract: A method and apparatus for monitoring and controlling the nano-scale flow rate of fluid in the operating flow path of a HPLC system. A first flow sensor is disposed in a first flow path between a first flow-divider and a fluidic tee. A second flow sensor is disposed in a second flow path between a second flow-divider and the fluidic tee. A first recycle flow restrictor is disposed in the first recycle flow path in fluid communication with the first flow-divider. A second recycle flow restrictor is disposed in the second The permeability of each recycle flow restrictor can be selected to produce a desired flow rate with each respective flow path. The output signals of the first and second flow sensors to control output of a pump within each flow path.

Abstract: An ion detector for a mass spectrometer is disclosed comprising one or more microchannel plates and an anode arranged to receive electrons emitted from the one or more microchannel plates. The anode preferably has a smaller diameter than the microchannel plates and is preferably arranged at a distance of at least 15 mm from the microchannel plates. One or more focusing lenses may be provided intermediate the microchannel plates and the anode. The anode preferably comprises two portions separated by an electrically insulated layer.

Abstract: An ion detector for a mass spectrometer is disclosed comprising a microchannel plate 8 which receives ions 12 at an input surface and releases electrons 16 from an output surface. A detecting device is arranged to receive at least some of the electrons 16 emitted from the microchannel plate 8. The detecting device receives electrons 16 on a first portion of the detecting device at a first time t1 and receives electrons 16 on a second different portion of the detector at a second later time t2. Time-varying electric and/or magnetic fields are applied between the microchannel plate 8 and the detecting device to guide electrons 16 emitted from the microchannel plate onto different regions of the detecting device in a time varying manner.

Abstract: A mass spectrometer is disclosed comprising an electric field region L2 wherein a time-varying electric field is applied thereto. In a mode of operation a pulse of ions 3 comprising ions having different mass to charge ratios passes through the electric field region L2 and the electric field is varied with time such that at least some of the ions 3 having different mass to charge ratios subsequently arrive at the extraction or acceleration region 10 of a Time of Flight mass analyser at substantially the same time.

Abstract: Disclosed herein is a method of analyzing three-dimensional data obtained from a chromatography/spectrometry process, in particular an LC/MS process using a two-dimensional multi-variant statistical analysis. The LC portion permits separation of analytes within a sample. The information obtained from such a procedure typically depends on retention time (Rt). As the analytes progress through the system, they enter the MS region of the LC/MS system. There they are ionized and a mass detector then detects these ionized species. The information procured from this procedure is generally reported as intensity for a corresponding m/z value. Therefore, an LC/MS system provides at least three pieces of information. Principle component analysis (PCA) is a robust method of multi-variant analysis of this type of data between different samples. However, typically, PCA analysis is performed using only two-dimensional data.

Abstract: A solid phase extraction (SPE) device having a reservoir with an opening; a well comprising an internally tapered wall, the well having a wider interior diameter at an end closest to the opening than at an exit spout; a first filter within the well; a bed of sorbent particles within the well below the first filter; and a second filter having a diameter smaller than the first filter within the well below the bed of sorbent particles and above the exit spout is provided. A method of performing SPE using the device is also provided.

Abstract: An Atmospheric Pressure Chemical Ionisation ion source is disclosed wherein the current applied to a corona needle 2 is repeatedly varied between two or more settings during a single experimental run or acquisition. Two or more separate sets of mass spectral or mass analysed data are obtained. The ion source in one embodiment comprises a heated tube 1 arranged to discharge gas and analyte into a housing 7 enclosing corona needle 2. The housing 7 comprises a gas outlet port 3 via which analyte ions exit. According to another embodiment the corona needle does not have to be enclosed within a housing.

Abstract: An ion detector 7 for a mass spectrometer is disclosed comprising a microchannel plate 8 which receives ions 12 at an input surface and releases secondary electrons 16 from an output surface. A detecting device 9 having a detecting surface is arranged to receive at least some of the electrons 16 emitted by the microchannel plate 8. The area of the detecting surface is substantially greater than the area of the output surface of the microchannel plate 8.

Abstract: An ion detector for a mass spectrometer is disclosed comprising one or more microchannel plates and an anode arranged to receive electrons emitted from the one or more microchannel plates. The anode is permanently magnetized and electrons emitted from the microchannel plates preferably spiral around lines of magnetic field towards the anode.

Abstract: The invention features an optical medium for calibrating UV absorbance detectors, methods for making such an optical medium, and methods for calibrating UV absorbance detectors using such a medium. The optical calibration medium includes a gel-sol silica glass monolith with a rare-earth dopant therein. The rare-earth dopant exhibits at least one spectral feature in at least the far UV range. The constituents of the gel-sol silica glass monolith are selected so the rare-earth doped sol-gel glass monolith exhibits a transmittance in the far UV range so each distinct spectral feature of the rare-earth dopant in the far UV range is discernable. The transmittance in a particular embodiment is at least about 50% at about 250 nm. The rare earth materials selected for use as dopants are those exhibiting a wide range of spectral features, preferably over a range from about 190 nm to about 700 nm and more particularly exhibit at least one distinct spectral feature in the range from about 190 nm to about 300 nm.

Abstract: Gradient performance with high pressure gradient solvent delivery system is optimized by approximation of infinite stroke volume of high pressure pumps by the addition of pulse dampening with backflow prevention to each high pressure pump. The backflow prevention adds sufficient minimum flow resistance, thereby enhancing the performance of the pulse dampening over a wider range of flow rates resulting in consistent gradient performance.

Abstract: A photometric measurement flow cell having measurement path-lengths that can be adjusted down to less than 0.1 mm. The measurement path-length is controlled by both a common flow cell body and the dimensional parameters of a stepped sealing optical element. The stepped optical element includes a stem portion that can be made in various lengths to create a family flow cell measurement path-lengths. The replacement of one stepped element with another having a different stem length within the flow cell creates a reliable method to adjust the measured path-length of the flow cell.