Cheng I Lee

US Patent:

6929730, Aug 16, 2005

Filed:

May 1, 2002

Appl. No.:

10/135385

Inventors:

Cheng Sheng Lee - Ellicott City MD, US
Donald Lad DeVoe - Bethesday MD, US

International Classification:

G01N027/447
G01N027/453

US Classification:

204451, 204601

Abstract:

One embodiment of the invention relates to a microfluidic apparatus for performing two dimensional biomolecular separations. According to one aspect of the invention, after a first dimension separation in a first microchannel, the sample material is electrokinetically and simultaneously transferred to an array of microchannels in the second dimension (e. g. , by changing the electric potentials at the reservoirs connected to the microchannels). Preferably any separation accomplished in the first dimension is completely retained upon transfer to the second dimension. According to another aspect of the invention, the separation in the second dimension is performed using a temperature gradient (e. g. , a spatial or temporal temperature gradient). According to one embodiment of the invention, the biomolecular material comprises DNA and the first dimension separation is a sized-based separation and the second dimension separation is a sequence-based separation.

US Patent:

6974526, Dec 13, 2005

Filed:

May 1, 2002

Appl. No.:

10/135386

Inventors:

Cheng Sheng Lee - Ellicott City MD, US
Don DeVoe - Bethesda MD, US

Assignee:

Calibrant Biosystems, Inc. - Rockville MD
The University of Maryland - Riverdale MD

International Classification:

G01N027/447
G01N027/453

US Classification:

204451, 204601

Abstract:

The invention provides a microfluidic apparatus for performing 2-D biomolecular separations. The microfluidic 2-D device may include first and second planar substrates which include at least a first dimension microchannel extending in a first direction and an array of second dimension microchannels extending in a second direction, preferably, orthogonal to the first dimension. The ends of at least some of the microchannels are in fluid communication with a plurality of reservoirs. The substrates may further include a number of microchannels and reservoirs. The reservoirs are in electrical communication with a plurality of electrodes and voltage power sources. The device enables two dimensional separations of proteins and other biomolecules. According to another aspect of the invention, an isoelectric point based separation is enabled in a first dimension, and a size based separation in a second dimension.

US Patent:

7070682, Jul 4, 2006

Filed:

Jan 15, 2002

Appl. No.:

10/047759

Inventors:

Cheng Lee - Ellicott City MD, US
Don DeVoe - Bethesda MD, US

International Classification:

G01N 27/447
G01N 27/453

US Classification:

204462, 204613

Abstract:

The invention relates to an apparatus for performing gel protein extractions and methods of using the apparatus.

US Patent:

7641780, Jan 5, 2010

Filed:

Mar 23, 2005

Appl. No.:

11/086400

Inventors:

Cheng Sheng Lee - Ellicott City MD, US
Don DeVoe - Bethesda MD, US

Assignee:

Calibrant Biosystems, Inc. - Rockville MD
The University of Maryland - Riverdale MD

International Classification:

G01N 27/453
G01N 30/02
B01L 3/00

US Classification:

204601, 422 70, 422 99

Abstract:

The invention provides a microfluidic apparatus for performing 2-D biomolecular separations. The microfluidic 2-D device may include first and second planar substrates which include at least a first dimension microchannel extending in a first direction and an array of second dimension microchannels extending in a second direction, preferably, orthogonal to the first dimension. The ends of at least some of the microchannels are in fluid communication with a plurality of reservoirs. The substrates may further include a number of microchannels and reservoirs. The reservoirs are in electrical communication with a plurality of electrodes and voltage power sources. The device enables two dimensional separations of proteins, DNA and other biomolecules. According to another aspect of the invention, an array of tertiary microchannels extending in a third direction may be utilized.

US Patent:

51511649, Sep 29, 1992

Filed:

Feb 9, 1990

Appl. No.:

7/477755

Inventors:

William C. Blanchard - Phoenix MD
Cheng S. Lee - Columbia MD

Assignee:

The University of Maryland - College Park MD
Blanchard and Co. - Phoenix MD

International Classification:

G01N 2726

US Classification:

2041821

Abstract:

Capillary zone electrophoresis is enhanced by the application of an electric field across the interior of the capillary tube. This external electric field is applied through a conductive member at the exterior of the capillary tube. The external field vectorially couples with the internal field, controlling the polarity and the magnitude of the surface (zeta) potential on the interior surface of the capillary. The control of the surface (zeta) potential reduces adsorption of macromolecular onto the interior surface of the capillary tube, by inducing electrostatic repulsions between the macromolecules, and the capillary surface. Additionally, the control of the surface (zeta) potential can retard, and even reverse, electroosmotic flow, depending upon the magnitude of those fields.

US Patent:

20140342949, Nov 20, 2014

Filed:

Mar 14, 2014

Appl. No.:

14/213015

Inventors:

YuHuang WANG - Laurel MD, US
Jia HUANG - Shanghai, CN
Allen NG - Silver Spring MD, US
Yanmei PIAO - College Park MD, US
Cheng S. LEE - Ellicott City MD, US

Assignee:

University of Maryland, College Park - College Park MD

International Classification:

G01N 27/22
B01J 19/12
G01N 33/00
G01N 33/543

US Classification:

506 32, 422 8202, 422 69, 506 39

Abstract:

The present invention is directed to tube-in-a-tube electronic materials and electronic chemical sensors comprising tube-in-a-tube configurations such as covalently functionalized double-walled carbon nanotubes.