Biocept, Inc.

Pavel Tsinberg

Stephen D Mikolajczyk

Tony Pircher

Ram S Bhatt

Soonkap Hahn

Zhongliang Tang

Farideh Z Bischoff

Roberto Fagnani

Xiaofan Dong

Yehudit Falcovitz-Gerassi

Carl Frederick Edman

Jhobe Steadman

Tim Watanaskul

Pat Roycroft

Sandra Matsumoto

Yehudit Gerassi

Stephen Mikolajczyk

Ram Bhatt

The present invention provides a device for isolating target biomolecules or cells from samples, particularly biological samples. In particular, the device comprises a loading mixture, which contains the biological sample and a first binding entity that specifically binds to the target biomolecule or target cell; and a micro-channel coated with a second binding entity that binds directly or indirectly to the first binding entity. Methods of capturing, detecting, and/or evaluating target biomolecules or target cells (e.g. cancer cells) in biological samples are also disclosed.

Devices and methods of cell capture and analysis

A micro flow device () for separating or isolating cells from a bodily fluid or other liquid sample uses a flow path where straight-line flow is interrupted by a pattern of transverse posts (). The posts are spaced across the width of an expanded collection chamber region () in the flow path, extending between the upper and lower surfaces thereof; they have rectilinear surfaces, being curved in cross-sections, e.g. circular or tear-drop shaped, and are randomly arranged so as to disrupt streamlined flow. The device is oriented so that its lower surface is aligned at about 45&#xb0; to the horizontal. Sequestering agents, such as Abs, which are attached to surfaces of the collection region via a hydrophilic coating, preferably a permeable hydrogel containing isocyanate moieties, are highly effective in capturing cells or other targeted biomolecules while the remainder of the liquid sample exits horizontally.

Cell separation using microchannel having patterned posts

The present invention provides methods for preventing clumping of cells in microfluidic devices by addition of diazolidinyl urea (DU). DU can be added to samples at the time of collection or can be added to samples post-collection. DU can also be pre-added to sample collection devices.

Use of diazolidinyl urea for anti-clumping of biological samples

A microflow apparatus for separating or isolating cells from a bodily fluid or other liquid sample uses a flow path where straight-line flow is interrupted by a pattern of transverse posts. The posts are spaced across the width of a collection region in the flow path, extending between the upper and lower surfaces thereof; they have rectilinear surfaces, have arcuate cross-sections, and are randomly arranged so as to disrupt streamlined flow. Sequestering agents, such as Abs, are attached to all surfaces in the collection region via a hydrophilic coating, preferably a hydrogel containing isocyanate moieties or a PEG or polyglycine of substantial length, and are highly effective in capturing cells or other targeted biomolecules as a result of such streamlined flow disruption.

Recovery of rare cells using a microchannel apparatus with patterned posts

A microflow device for separating or isolating cells from a bodily fluid or other liquid sample uses a flow path where straight-line flow is interrupted by a pattern of transverse posts which are arranged across the width of a collection region in an irregular or set random pattern so as to disrupt streamlined flow. Sequestering agents, such as Abs, are attached to all surfaces in the collection region via a hydrophilic permeable hydrogel coating. The collection region is formed as a cavity in a body molded from PDMS, which flexible body is sandwiched between a glass slide or comparable flat plate and a rigid top cap plate, both of which are pressed into abutting relation with the PDMS body by a heat-shrunk polymeric sleeve. Following cell separation and washing, cells can be released from the sequestering agents and the device centrifuged to force said cells to collect adjacent the hydrogel-coated slide or plate. Slitting the polymeric sleeve allows the body to then be peeled from the slide or plate, using an integral tab, to expose the separated cells on the top surface thereof for ready microscopic examination.

Device for cell separation and analysis and method of using

A biochip is formed with a plurality of optically clear hydrogel cells attached to the top surface of a solid substrate in the form of an array. Each of the cells is formed of a hydrogel of polyethylene glycol, polypropylene glycol or a copolymer thereof having reactive isocyanate groups. Binding entities are immobilized in these cells, which entities are effective to selectively hybridize to or sequester a target biomolecule. Different binding entities are immobilized in different cells in an array to create a biochip that can be used to assay for a number of target biomolecules.

Three dimensional format biochips

A method of making a microarray by coating a flat substrate with a polymerizable hydrogel layer which contains anchoring moieties dispersed uniformly therethroughout. Following curing, a continuous layer of uniform thickness is securely attached to the upper surface of the substrate through an array region thereof. A plurality of different probes are then attached to create microspots at distinct spatial locations on the surface of this slab layer by linking the probes to the anchoring moieties in the cured hydrogel. Such anchoring moieties may employ linking systems such as organic chelators, that are activated by copper or some other metal, and complementary pairs such as avidin-biotin.

Microarrays utilizing hydrogels

Spheroidal beads present an exterior surface of a hydrophilic hydrogel, which is an isocyanate-functional polymer that is polymerized by urethane bonds and cross-linked by urethane and urea bonds. Sequestering agents present at the surface are covalently bound to isocyanate groups or to intermediate linkers that are so bound. These beads allow sequestering agents to retain their native three-dimensional configuration, and as a result of such surface characteristics and hydrophilicity, they achieve highly effective capture of very small subpopulations of rare cells from bodily fluids or the like and very effectively deter nonspecific binding of other biomaterials present in such bodily fluid. They may be all-hydrogel spheroids or hydrogel-coated substrates.

Beads for capturing target cells from bodily fluid

A post-incubation treatment is employed to effectively remove targets, such as proteins/protein complexes, or other label-bearing moieties that may non-specifically bind to a microarray substrate during a binding assay. Following incubation, a one-step wash is carried out with a liquid containing digester, e.g., a digestive enzyme (protease) or lysosome, which is effective to remove non-specifically bound targets or at least labeled portions of such targets from the substrate. Proteases are bound to or coated onto large molecules or onto solid particles of such a size such that they are prohibited from entering the porous surfaces of 3-D hydrogel microspots and are unable to reach and digest labeled target-probe complexes that are disposed within such porous hydrogel microspots. Digested segments of such protein which contain labels (or of essentially the entire protein) are carried away in the wash liquid and thus are not present to create background noise during imaging.

Alleviation of non-specific binding in microarray assays

A novel hybridization device that improves the efficiency and consistency of microarray hybridization reactions by achieving a greater degree of internal mixing of target solution. The device provides a gasket-and-cover-type chamber wherein solution mixing is achieved by the creation of a multitude of microbubbles. One or more of the inner walls that define the chamber contain bubble-rupturing elements that extend into the chamber and terminate in sharp edges. They are typically located on opposite sides of a rectangular chamber and are pointed in a direction opposing bubble movement. Their interference with larger bubbles causes their breakup into microbubbles which travel separate and distinct paths as a result of external agitation and thereby provide improved solution mixing that results in a uniform distribution of target molecules to the probe molecules bound to the substrate. The sensitivity and consistency of the hybridization reaction is significantly increased.

Microarray hybridization device having bubble-fracturing elements

Microwell biochips () are formed from a thin flat plate () of polymeric material having a plurality of regularly spaced holes () that extend completely therethrough and create microwells. The lower end of each hole is closed by a microporous, hydrophobic, polymeric membrane () laminated to the undersurface of the plate which retains an aqueous test solution in the wells until a vacuum is applied to the undersurface thereof to effect draining of the solution and of any wash solution that might be subsequently added. A spot of polymerizing isocyanate-functional hydrogel is applied generally centrally to the porous membrane surface at the bottom of each well in a manner so as to cover only a minor portion of the surface and out of contact with the well sidewalls, thus leaving substantial surface area through which drainage can be readily effected. Biological capture agents are associated with the polymerizing hydrogel so as to become immobilized as a part thereof.

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Carlsbad, CA, United States of America

Pavel Tsinberg