Patents by Inventor Gregory J. Fiechtner
Gregory J. Fiechtner has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 8911606Abstract: Disclosed herein are methods and devices for dielectrokinetic chromatography. As disclosed, the devices comprise microchannels having at least one perturber which produces a non-uniformity in a field spanning the width of the microchannel. The interaction of the field non-uniformity with a perturber produces a secondary flow which competes with a primary flow. By decreasing the size of the perturber the secondary flow becomes significant for particles/analytes in the nanometer-size range. Depending on the nature of a particle/analyte present in the fluid and its interaction with the primary flow and the secondary flow, the analyte may be retained or redirected. The composition of the primary flow can be varied to affect the magnitude of primary and/or secondary flows on the particles/analytes and thereby separate and concentrate it from other particles/analytes.Type: GrantFiled: October 10, 2013Date of Patent: December 16, 2014Assignee: Sandia CorporationInventors: Gabriela S. Chirica, Gregory J. Fiechtner, Anup K. Singh
-
Patent number: 8702946Abstract: Disclosed herein are methods and devices for dielectrokinetic chromatography. As disclosed, the devices comprise microchannels having at least one perturber which produces a non-uniformity in a field spanning the width of the microchannel. The interaction of the field non-uniformity with a perturber produces a secondary flow which competes with a primary flow. By decreasing the size of the perturber the secondary flow becomes significant for particles/analytes in the nanometer-size range. Depending on the nature of a particle/analyte present in the fluid and its interaction with the primary flow and the secondary flow, the analyte may be retained or redirected. The composition of the primary flow can be varied to affect the magnitude of primary and/or secondary flows on the particles/analytes and thereby separate and concentrate it from other particles/analytes.Type: GrantFiled: May 29, 2008Date of Patent: April 22, 2014Assignee: Sandia CorporationInventors: Gabriela S. Chirica, Gregory J. Fiechtner, Anup K. Singh
-
Patent number: 7931792Abstract: Disclosed is a device for separating and concentrating particles suspended in a fluid stream by using dielectrophoresis (DEP) to trap and/or deflect those particles as they migrate through a fluid channel. The method uses fluid channels designed to constrain a liquid flowing through it to uniform electrokinetic flow velocities. This behavior is achieved by connecting deep and shallow sections of channels, with the channel depth varying abruptly along an interface. By careful design of abrupt changes in specific permeability at the interface, an abrupt and spatially uniform change in electrokinetic force can be selected. Because these abrupt interfaces also cause a sharp gradient in applied electric fields, a DEP force also can be established along the interface.Type: GrantFiled: September 11, 2008Date of Patent: April 26, 2011Assignee: Sandia CorporationInventors: Gregory J. Fiechtner, Eric B. Cummings, Anup K. Singh
-
Patent number: 7666289Abstract: Disclosed herein are methods and devices for assaying and concentrating analytes in a fluid sample using dielectrophoresis. As disclosed, the methods and devices utilize substrates having a plurality of pores through which analytes can be selectively prevented from passing, or inhibited, on application of an appropriate electric field waveform. The pores of the substrate produce nonuniform electric field having local extrema located near the pores. These nonuniform fields drive dielectrophoresis, which produces the inhibition. Arrangements of electrodes and porous substrates support continuous, bulk, multi-dimensional, and staged selective concentration.Type: GrantFiled: September 2, 2008Date of Patent: February 23, 2010Assignee: Sandia CorporationInventors: Blake A. Simmons, Eric B. Cummings, Gregory J. Fiechtner, Yolanda Fintschenko, Gregory J. McGraw, Allen Salmi
-
Patent number: 7534334Abstract: Disclosed is a device for separating and concentrating particles suspended in a fluid stream by using dielectrophoresis (DEP) to trap and/or deflect those particles as they migrate through a fluid channel. The method uses fluid channels designed to constrain a liquid flowing through it to uniform electrokinetic flow velocities. This behavior is achieved by connecting deep and shallow sections of channels, with the channel depth varying abruptly along an interface. By careful design of abrupt changes in specific permeability at the interface, an abrupt and spatially uniform change in electrokinetic force can be selected. Because these abrupt interfaces also cause a sharp gradient in applied electric fields, a DEP force also can be established along the interface.Type: GrantFiled: September 30, 2004Date of Patent: May 19, 2009Assignee: Sandia CorporationInventors: Gregory J. Fiechtner, Eric B. Cummings, Anup K. Singh
-
Patent number: 7527977Abstract: The present embodiment describes a miniature, microfluidic, absorption-based sensor to detect proteins at sensitivities comparable to LIF but without the need for tagging. This instrument utilizes fiber-based evanescent-field cavity-ringdown spectroscopy, in combination with faceted prism microchannels. The combination of these techniques will increase the effective absorption path length by a factor of 103 to 104 (to ˜1-m), thereby providing unprecedented sensitivity using direct absorption. The coupling of high-sensitivity absorption with high-performance microfluidic separation will enable real-time sensing of biological agents in aqueous samples (including aerosol collector fluids) and will provide a general method with spectral fingerprint capability for detecting specific bio-agents.Type: GrantFiled: March 22, 2005Date of Patent: May 5, 2009Assignee: Sandia CorporationInventors: Julie A. Fruetel, Gregory J. Fiechtner, Dahv A. V. Kliner, Andrew McIlroy
-
Publication number: 20090045064Abstract: Disclosed herein are methods and devices for assaying and concentrating analytes in a fluid sample using dielectrophoresis. As disclosed, the methods and devices utilize substrates having a plurality of pores through which analytes can be selectively prevented from passing, or inhibited, on application of an appropriate electric field waveform. The pores of the substrate produce nonuniform electric field having local extrema located near the pores. These nonuniform fields drive dielectrophoresis, which produces the inhibition. Arrangements of electrodes and porous substrates support continuous, bulk, multi-dimensional, and staged selective concentration.Type: ApplicationFiled: September 2, 2008Publication date: February 19, 2009Inventors: Blake A. Simmons, Eric B. Cummings, Gregory J. Fiechtner, Yolanda Fintschenko, Gregory J. McGraw, Allen Salmi
-
Publication number: 20090008256Abstract: Disclosed is a device for separating and concentrating particles suspended in a fluid stream by using dielectrophoresis (DEP) to trap and/or deflect those particles as they migrate through a fluid channel. The method uses fluid channels designed to constrain a liquid flowing through it to uniform electrokinetic flow velocities. This behavior is achieved by connecting deep and shallow sections of channels, with the channel depth varying abruptly along an interface. By careful design of abrupt changes in specific permeability at the interface, an abrupt and spatially uniform change in electrokinetic force can be selected. Because these abrupt interfaces also cause a sharp gradient in applied electric fields, a DEP force also can be established along the interface.Type: ApplicationFiled: September 11, 2008Publication date: January 8, 2009Inventors: Gregory J. Fiechtner, Eric B. Cummings, Anup K. Singh
-
Patent number: 7347923Abstract: Embodiments of the present invention provide methods and devices for manipulating particles using dielectrophoresis. Insulating ridges and valleys are used to generate a spatially non-uniform electrical field. Particles may be concentrated, separated, or captured during bulk fluid flow in a channel having insulating ridges and valleys.Type: GrantFiled: October 3, 2003Date of Patent: March 25, 2008Assignee: Sandia CorporationInventors: Eric B. Cummings, Gregory J. Fiechtner
-
Patent number: 7344681Abstract: The present embodiment describes a laminar-mixing embodiment that utilizes simple, three-dimensional injection. Also described is the use of the embodiment in combination with wide and shallow sections of channel to affect rapid mixing in microanalytical systems. The shallow channel sections are constructed using all planar micromachining techniques, including those based on isotropic etching. The planar construction enables design using minimum dispersion concepts that, in turn, enable simultaneous mixing and injection into subsequent chromatography channels.Type: GrantFiled: October 6, 2004Date of Patent: March 18, 2008Assignee: Sandia CorporationInventors: Gregory J. Fiechtner, Anup K. Singh, Boyd J. Wiedenman
-
Patent number: 7106436Abstract: A triple-pump coherent anti-Stokes Raman scattering (CARS) system for simultaneous measurements of temperature and species concentrations with high spatial and temporal resolution is described, wherein four laser beams generate CARS signals near two distinct wavelengths exhibiting an N2 CARS signal along with the CARS signal from another target molecule, each pair of CARS signals generated over a relatively narrow wavelength region and captured with fixed-wavelength detection. Temperature and relative concentrations of the target species with respect to N2 are extracted by fitting the measured CARS spectrum in each wavelength region.Type: GrantFiled: December 3, 2003Date of Patent: September 12, 2006Assignee: The United States of America as represented by the Secretary of the Air ForceInventors: James R. Gord, Sukesh Roy, Robert P. Lucht, Michael S. Brown, Gregory J. Fiechtner
-
Patent number: 7005301Abstract: A low-dispersion methodology for designing microfabricated conduction channels for on-chip electrokinetic-based systems is presented. The technique relies on trigonometric relations that apply for ideal electrokinetic flows, allowing faceted channels to be designed on chips using common drafting software and a hand calculator. Flows are rotated and stretched along the abrupt interface between adjacent regions with differing permeability. Regions bounded by interfaces form flow “prisms” that can be combined with other designed prisms to obtain a wide range of turning angles and expansion ratios while minimizing dispersion. Designs are demonstrated using two-dimensional numerical solutions of the Laplace equation.Type: GrantFiled: June 6, 2003Date of Patent: February 28, 2006Assignee: Sandia National LaboratoriesInventors: Eric B. Cummings, Gregory J. Fiechtner
-
Publication number: 20030230489Abstract: A low-dispersion methodology for designing microfabricated conduction channels for on-chip electrokinetic-based systems is presented. The technique relies on trigonometric relations that apply for ideal electrokinetic flows, allowing faceted channels to be designed on chips using common drafting software and a hand calculator. Flows are rotated and stretched along the abrupt interface between adjacent regions with differing permeability. Regions bounded by interfaces form flow “prisms” that can be combined with other designed prisms to obtain a wide range of turning angles and expansion ratios while minimizing dispersion. Designs are demonstrated using two-dimensional numerical solutions of the Laplace equation.Type: ApplicationFiled: June 6, 2003Publication date: December 18, 2003Inventors: Eric B. Cummings, Gregory J. Fiechtner