Integrated monolithic microfabricated electrospray and liquid chromatography system and method

• US 6,464,866 B2
• Filed: 12/21/2000
• Issued: 10/15/2002
• Est. Priority Date: 09/17/1998
• Status: Expired due to Term

• Current Assignee: Rheonix, Inc.
• Original Assignee: Kionix Incorporated (ROHM Co., Ltd.)
• Inventors: Davis, Timothy J., Moon, James E., Galvin, Gregory J.
• Primary Examiner(s): Therkorn, Ernest G.
• Application Number:
  US09/747,080
• Publication Number:
  US 20010001452A1
• Time in Patent Office: 663 Days
• Field of Search: 250/288, 250/288.A, 210/656, 210/748, 210/198.2, 210/243, 204/600, 422/70, 436/161
• US Class Current: 210/198.2
• CPC Class Codes: G01N 30/6095 Micromachined or nanomachined, e.g. micro- or nanosize
• CPC Class Codes: G01N 30/7266 by electric field, e.g. electrospray
• CPC Class Codes: H01J 49/0018 Microminiaturised spectrometers, e.g. chip-integrated devices, Micro-Electro-Mechanical Systems [MEMS]
• CPC Class Codes: H01J 49/167 Capillaries and nozzles specially adapted therefor; electrostatic spraying per se B05B5/00
• CPC Class Codes: Y10T 29/49002 Electrical device making
• CPC Class Codes: Y10T 436/25375 Liberation or purification of sample or separation of material from a sample [e.g., filtering, centrifuging, etc.]
• CPC Class Codes: Y10T 436/255 including use of a solid sorbent, semipermeable membrane, or liquid extraction

Abstract

An electrospray device, a liquid chromatography device and an electrosprayliquid 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.

Claims

1. An integrated chemical analysis system, comprising:

a first substrate having a major surface;

a second substrate attached to said first substrate;

a liquid chromatography system formed at least in part by reactive-ion etching and integrated in at least one of said first and said second substrates, said liquid chromatography system configured to receive a fluid for analysis and to process and dispense said fluid; and

an electrospray device formed at least in part by reactive-ion etching and integrated on said first substrate, said electrospray device having an injection surface configured to receive said processed fluid from said liquid chromatography system, said major surface being configured to electrospray said fluid.

2. The system of claim 1, wherein said major surface of said electrospray device is configured to electrospray said processed fluid in a direction substantially perpendicular to said major surface.

3. The system of claim 1, further comprising:

at least first and second liquid chromatography systems integrated in at least one of said first and second substrates and configured to receive at least first and second fluids for analysis and to process and dispense said fluids; and

at least first and second electrospray devices integrated on said first substrate and having at least first and second injection surfaces, respectively, and configured to receive said processed fluids from said at least first and second liquid chromatography systems, and having first and second major surfaces, respectively, configured to dispense said fluids by electrospraying said fluid.

4. The system of claim 1, wherein at least one of said first and second substrates is silicon.

5. The system of claim 1, wherein said second substrate is attached to said first substrate by anodic bonding.

6. The system of claim 1, further comprising controlling circuitry for said integrated chemical analysis system, said circuitry being integrated on at least first and second substrates.