DANIEL CHU, PHARM.D.
Pharmacy at Geary Blvd, San Francisco, CA

5284565, Feb 8, 1994

Dec 23, 1992

7/995495

Daniel Y. Chu - San Francisco CA
Elaine R. Mardis - Hercules CA

Bio-Rad Laboratories, Inc. - Hercules CA

G01N 2726, G01N 27447

204299R

A comb to be used for holding samples and defining sample lanes in an ultra-thin slab gel in vertical slab gel electrophoresis is constructed with to form tapered or wedged-shaped sample wells, with the narrowest edge of the wedge opening into the upper edge of the gel. In one embodiment, the comb has a wedge-shaped profile along the contact edge to provide an expanded well at each sample location. Notches alternating with grooves are cut into the wedge shape to form teeth which taper along orthogonal axes, the wells being defined by the space between each adjacent pair of teeth. The gel enclosure which holds the slab gel is formed by plates which are shaped along one edge to provide a complementary wedge-shaped opening leading into the gel space. The comb fits snugly into the opening with the teeth of the comb touching or extending a short distance into the upper exposed surface of the gel. In another embodiment, the comb has a rectangular profile, with grooves cut to a varying depth to form the wedge shape.

5540498, Jul 30, 1996

Jul 29, 1994

8/282241

Daniel Y. Chu - San Francisco CA

Bio-Rad Laboratories, Inc. - Hercules CA

B01F 1502, G05D 1102

3661604

Gradient gels for electrophoresis are produced by an apparatus in which a pair of syringes are mounted on a support rack together with cams arranged for synchronous rotation. Cam followers engaged by the cams are linked to the syringe barrels, with each cam defining a distinct spiral path translated by one of the cam followers into a preselected rate or rate profile of volumetric discharge from one of the syringes as the cam rotates. With the rate or rate profile established by one cam being distinct from the rate or rate profile established by the other, a gradient or other variation in composition is obtained when the syringe discharges are combined into a common stream and directed to the gel enclosure for solidification into a gel. The gradient or variation in composition is determined by the cam profiles alone, and is independent of the rate at which the cams are rotated, and of whether or not the rotation is performed in a steady manner. The apparatus can be readily designed for manual operation with highly accurate and reproducible results.

7771933, Aug 10, 2010

May 21, 2004

10/851682

German Arciniegas - Berkeley CA, US
Jeff Ceremony - Fairfield CA, US
Daniel Y. Chu - San Francisco CA, US
Charles W. Ragsdale - Concord CA, US

Bio-Rad Laboratories, Inc. - Hercules CA

C12M 1/34, C12Q 1/68, C12P 19/34

435 6, 4352872, 219201

Individual temperature control in multiple reactions performed simultaneously in a spatial array such as a multi-well plate is achieved by thermoelectric modules with individual control, with each module supplying heat to or drawing heat from a single region within the array, the region containing either a single reaction vessel or a group of reaction vessels.

4699706, Oct 13, 1987

May 30, 1986

6/868964

Samuel Burd - Oakland CA
Daniel Y. Chu - San Francisco CA

Bio-Rad Laboratories, Inc. - Richmond CA

G01N 2728, B01D 1300, B01D 3506

204301

Electrophoretic extraction of molecular species from a separation medium such as a gel segment is achieved by placing the separation medium in a tube closed at one end by a retaining material such as glass frit, and sealing the closed end of the tube against the mouth of a receiving cup which has a semi-permeable membrane (such as a dialysis membrane) for its bottom. The tube with receiving cup attached is inserted in a tube electrophoresis cell such as those commonly used in analytical laboratories. As current passes through the tube, the molecular species migrates from the separation medium to pass through the retaining frit and collect on the membrane for subsequent recovery.