Abstract:
An ultra-low volume fraction collection and concentration method provides practical application in collecting fractions, e.g. as low as 25 nL, from nanoLC columns into pipette tips at user-defined timed-intervals. The fractions are dried to create a concentrated band at the very end of the interior of the pipette tip and subsequently reconstituted directly in the pipette tips in solvent prior to analysis. As the chromatography and reconstitution solvent choice are independent, the reconstitution solvent can be selected to maximize ionization efficiency without compromising chromatography separation, hi the infusion analysis of the nanoLC fractions, a low flow electrospray chip enables each nanoLC fraction to be analyzed for over ten minutes. This increase in analysis time allows for advantages over prior methods. Optionally, the nanoLC fractions can be archived in the pipette tips for analysis at a later date.
Abstract:
A microfabricated silicon chip with a separation material, such as in situ prepared porous polymer monoliths (254) in its microchannels is disclosed. The polymer monoliths are liquid-permeable and serve as microcolumns for liquid chromatography, which are prepared by in situ radical polymerization of a mixture containing vinyl monomers and solvents (porogen) in the microchannels. A method and system are disclosed to generate one or more electrospray plumes from one or more nozzles that provide an ion intensity as measured by a mass spectrometer that is approximately proportional to the number of electrospray plumes formed for analyses contained within the fluid. A plurality of electrospray devices (250) can be used in the form of an array of miniaturized separate electrospray devices for the purpose of generating multiple electrospray plumes from multiple nozzles (242) for the same fluid for analysis.
Abstract:
A droplet/electrospray device and a liquid chromatography-electrospray system are disclosed. The droplet/electrospray device (100) comprises a substrate (102) defining a channel (104) between an entrance orifice (106) on an injection surface (108) and an exit orifice on an ejection surface (112), a nozzle (110) defined by a portion recessed from the ejection surface (112) surrounding the exit orifice, and an electrode (122) for application of an electric potential to the substrate (102) to optimize and generate droplets or an electrospray (62). A plurality of these electrospray devices (100) can be used in the fonn of an array of miniaturized nozzles. The liquid chromatography-electrospray device (160) comprises a separation substrate (162) defining an introduction channel (164) between an entrance orifice and a reservoir (166) and a separation channel (168) between the reservoir (166) and an exit orifice (170), the separation channel (168) being populated with separation posts (174) perpendicular to the fluid flow.
Abstract:
An electrospray device, a liquid chromatography device and an electrospray-liquid chromatography system are disclosed. The electrospray device comprises a substrate defining a channel between an entrance orifice on an injection surface and an exit orifice on an ejection surface, a nozzle defined by a portion recessed from the ejection surface surrounding the exit orifice, and an electrode for application of an electric potential to the substrate to optimize and generate an electrospray; and, optionally, additional electrode(s) to further modify the electrospray. The liquid chromatography device comprises a separation substrate defining an introduction channel between an entrance orifice and a reservoir and a separation channel between the reservoir and an exit orifice, the separation channel being populated with separation posts perpendicular to the fluid flow; a cover substrate bonded to the separation substrate to enclose the reservoir and the separation channel adjacent the cover substrate; and, optionally, electrode(s) for application of a electric potential to the fluid. The exit orifice of the liquid chromatography device may be homogeneously interfaced with the entrance orifice of the electrospray device to form an integrated single system. An array of multiple systems may be fabricated in a single monolithic chip for rapid sequential fluid processing and generation of electrospray for subsequent analysis, such as by positioning the exit orifices of the electrospray devices near the sampling orifice of a mass spectrometer.
Abstract:
An electrospray device comprises a capillary tube (52) having a passage for conducting fluids through the capillary tube and connecting an entrance orifice and an exit orifice (56). First and the second electrodes are positioned to define an electric field surrounding the exit orifice (56). The first electrode (70) circumscribes the capillary tube proximate the exit orifice, and the second electrode imparts a second potential to the fluid. A mass spectrometry device may be provided to receive fluid droplets/sprays of fluid (60,62) from the exit orifice (56).
Abstract:
A microchip-based electrospray device, system, and method of fabrication thereof are disclosed. The electrospray device (250) includes a substrate (200) defining a channel (224) between an entrance orifice on an injection surface and an exit orifice on an ejection surface, a nozzle (232) defined by a portion recessed from the ejection surface surrounding the exit orifice, and an electric field generating source for application of an electric potential to the substrate to optimize and generate an electrospray (262). A method and system are disclosed to generate multiple electrospray plumes from a single fluid stream that provides an ion intensity as measured by a mass spectrometer that is approximately proportional to the number of electrospray plumes formed for analytes contained within the fluid. A plurality of electrospray nozzle devices (232) can be used in the form of an array of miniaturized nozzles for the purpose of generating multiple electrospray plumes (262) from multiple nozzles (232) for the same fluid stream . This invention dramatically increases the sensitivity of microchip electrospray devices (250) compared to prior disclosed systems and methods.
Abstract:
A robotic autosampler (1) provides for automated manipulation of microfluidic chips having multiple electrospray devices and/or sample inlets (113) for interface to a mass spectrometer (111) or other detection device. The autosampler also provides for connection of control voltages to the electrospray device to facilitate enablement, control and steering of charged droplets and ions. The autosampler further provides a method of fluid delivery that may be disposable or reusable. The delivery device may contain materials for component separation or sample purification. The delivery device may contain preloaded sample or the sample may be loaded by the autosampler. A method for automated manipulation of multiple electrosprays (115) in communication with a detector, includes: providing a robot autosampler having an electrospray chip (80); electrospraying at least one analyte from at least one electrospray device on the electrospray chip; and manipulating the electrospray chip in communication with a detector in a manner to detect analyte from the electrospray.
Abstract:
A dielectric film is provided which includes a base layer and a capping layer, preferably silicon oxynitride, wherein the film is an effective moisture and ion barrier when disposed between a conductive substrate and a liquid having an electrical potential different than the electrical potential of the substrate.
Abstract:
A microfabricated silicon chip with a separation material, such as in situ prepared porous polymer monoliths (254) in its microchannels is disclosed. The polymer monoliths are liquid-permeable and serve as microcolumns for liquid chromatography, which are prepared by in situ radical polymerization of a mixture containing vinyl monomers and solvents (porogen) in the microchannels. A method and system are disclosed to generate one or more electrospray plumes from one or more nozzles that provide an ion intensity as measured by a mass spectrometer that is approximately proportional to the number of electrospray plumes formed for analyses contained within the fluid. A plurality of electrospray devices (250) can be used in the form of an array of miniaturized separate electrospray devices for the purpose of generating multiple electrospray plumes from multiple nozzles (242) for the same fluid for analysis.
Abstract:
A droplet/electrospray device and a liquid chromatography-electrospray system are disclosed. The droplet/electrospray device (100) comprises a substrate (102) defining a channel (104) between an entrance orifice (106) on an injection surface (108) and an exit orifice on an ejection surface (112), a nozzle (110) defined by a portion recessed from the ejection surface (112) surrounding the exit orifice, and an electrode (122) for application of an electric potential to the substrate (102) to optimize and generate droplets or an electrospray (62). A plurality of these electrospray devices (100) can be used in the form of an array of miniaturized nozzles. The liquid chromatography-electrospray device (160) comprises a separation substrate (162) defining an introduction channel (164) between an entrance orifice and a reservoir (166) and a separation channel (168) between the reservoir (166) and an exit orifice (170), the separation channel (168) being populated with separation posts (174) perpendicular to the fluid flow.