Abstract: A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.

Abstract: A microscopic lens, of size approximately 1 micron is used for its optical characteristics.

Abstract: Methods and systems for operating an apertureless microscope for observing one or more features to a molecular sensitivity on objects are described. More particularly, the method includes moving a tip of a probe coupled to a cantilever in a vicinity of a feature of a sample, which emits one or more photons at a detected rate relative to a background rate of the sample based upon the presence of the tip of the probe in the vicinity of the feature. The method modifies the detected rate of the feature of the sample, whereupon the modifying of the detected rate causes the feature of the sample to enhance relative to background rate of the feature.

Abstract: The use of microfluidic structures enables high throughput screening of protein crystallization. In one embodiment, an integrated combinatoric mixing chip allows for precise metering of reagents to rapidly create a large number of potential crystallization conditions, with possible crystal formations observed on chip. In an alternative embodiment, the microfluidic structures may be utilized to explore phase space conditions of a particular protein crystallizing agent combination, thereby identifying promising conditions and allowing for subsequent focused attempts to obtain crystal growth.

Abstract: Valve structures formed in elastomer material are electrostatically actuated by applying voltage to a flexible, electrically conductive wire pattern. An actuation force generated between the patterned wire structure and an electrode result in closure of a flow channel formed in elastomer material underlying the wire. In one embodiment of a valve structure in accordance with the present invention, the wire structure is patterned by lithography and etching of a copper/polyimide laminate, with an underlying gold plate positioned on the opposite side of the flow channel serving as an electrode. In an alternative embodiment, a first wire structure is patterned by physically cutting out a first pattern of strips from an Aluminum/Mylar(®) laminate sheet. A second patterned wire structure serving as the electrode is formed by the same method, and positioned on the opposite side of a control channel.

Abstract: The present invention relates to microfluidic devices and methods facilitating the growth and analysis of crystallized materials such as proteins. In accordance with one embodiment, a crystal growth architecture is separated by a permeable membrane from an adjacent well having a much larger volume. The well may be configured to contain a fluid having an identity and concentration similar to the solvent and crystallizing agent employed in crystal growth, with diffusion across the membrane stabilizing that process. Alternatively, the well may be configured to contain a fluid having an identity calculated to affect the crystallization process. In accordance with the still other embodiment, the well may be configured to contain a material such as a cryo-protectant, which is useful in protecting the crystalline material once formed.

Abstract: The invention provides a microfabricated device for sorting cells based on a desired characteristic, for example, reporter-labeled cells can be sorted by the presence or level of reporter on the cells. The device includes a chip having a substrate into which is microfabricated at least one analysis unit. Each analysis unit includes a main channel, having a sample inlet channel, typically at one end, and a detection region along a portion of its length. Adjacent and downstream from the detection region, the main channel has a discrimination region or branch point leading to at least two branch channels. The analysis unit may further include additional inlet channels, detection points, branch points, and branch channels as desired. A stream containing cells is passed through the detection region, such that on average one cell occupies the detection region at a given time.

Abstract: A method for fabricating assembled structures. The method includes providing a tip structure, which has a first end, a second end, and a length defined between the first end and the second end. The second end is a free end. The method includes attaching a nano-sized structure along a portion of the length of the tip structure to extend a total length of the tip structure to include the length of the tip structure and a first length associated with the nano-sized structure. The method includes shortening the nano-sized structure from the first length to a second length. The method also includes pushing the nano-sized structure in a direction parallel to the second length to reduce the second length to a third length of the nano-sized structure along the direction parallel to the second length to cause the nano-sized structure to move along a portion of the length of the tip structure.

Abstract: High throughput screening of crystallization of a target material is accomplished by simultaneously introducing a solution of the target material into a plurality of chambers of a microfabricated fluidic device. The microfabricated fluidic device is then manipulated to vary the solution condition in the chambers, thereby simultaneously providing a large number of crystallization environments. Control over changed solution conditions may result from a variety of techniques, including but not limited to metering volumes of crystallizing agent into the chamber by volume exclusion, by entrapment of volumes of crystallizing agent determined by the dimensions of the microfabricated structure, or by cross-channel injection of sample and crystallizing agent into an array of junctions defined by intersecting orthogonal flow channels.

Abstract: Devices such as capillaries for capillary electrophoresis are formed by contacting a gel precursor with a substrate comprising a permeable material that has higher permeability for organic solvents than water. The gel precursor is made of a water soluble polymer having hydrophobic moieties in a solvent mixture comprising water and an organic solvent, wherein in the absence of the organic solvent, the polymer forms a self-assembled gel. The organic solvent is allowed to permeate through the permeable material resulting in the formation of the self-assembled gel.

Abstract: A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.

Abstract: A microlens structure such as a solid immersion lens structure is a radiation transmissive pliant elastomer cast to a desired shape and smoothness. A method for construction of a solid immersion lens structure includes providing a mold defining a lens shaped cavity in which a solid immersion lens is cast, casting a translucent liquid elastomeric material into the lens cavity, permitting the elastomeric material to set to form the solid immersion lens portion and removing the solid immersion lens portion from the mold. A specific material for use as the solid immersion lens is a translucent silicone elastomer of a refractive index greater than n=1.4, such as General Electric RTV 615.

Abstract: High-density microfluidic chips contain plumbing networks with thousands of micromechanical valves and hundreds of individually addressable chambers. These fluidic devices are analogous to electronic integrated circuits fabricated using large scale integration (LSI). A component of these networks is the fluidic multiplexor, which is a combinatorial array of binary valve patterns that exponentially increases the processing power of a network by allowing complex fluid manipulations with a minimal number of inputs. These integrated microfluidic networks can be used to construct a variety of highly complex microfluidic devices, for example the microfluidic analog of a comparator array, and a microfluidic memory storage device resembling electronic random access memories.

Abstract: A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.

Abstract: The present invention provides a microfluidic device for synthesizing an array of compounds and methods for using the same. In particular, the microfluidic device of the present invention comprises a solid support base, an elastomeric layer attached to the solid support, and a plurality of flow channels located within the interface between the solid support and the elastomeric layer. In addition, the solid support comprises a functional group for forming a bond with a reactive reagent. In some embodiments, the microfluidic device further comprises a second plurality of flow channels that intersect the first plurality of flow channels. A plurality of control channels are also present in the microfluidic devices of the present invention. The control channels can be actuated to regulate flow of fluids within the flow channel(s).

Abstract: High throughput screening of crystallization of a target material is accomplished by simultaneously introducing a solution of the target material into a plurality of chambers of a microfabricated fluidic device. The microfabricated fluidic device is then manipulated to vary the solution condition in the chambers, thereby simultaneously providing a large number of crystallization environments. Control over changed solution conditions may result from a variety of techniques, including but not limited to metering volumes of crystallizing agent into the chamber by volume exclusion, by entrapment of volumes of crystallizing agent determined by the dimensions of the microfabricated structure, or by cross-channel injection of sample and crystallizing agent into an array of junctions defined by intersecting orthogonal flow channels.

Abstract: Soft lithography with surface tension control is used to microfabricate extremely efficient solid immersion lenses (SILs) out of rubber elastomeric material for use in microscope type applications. In order to counteract the surface tension of the mold material in a negative mold that causes creep on a positive mold, material such as RTV is partially cured before use in order to allow the reticulation of polymer chains to change the viscosity of the uncured material in a controllable manner. In a specific embodiment, the techniques of soft lithography with surface tension control are used to make molded SILs out of the elastomer polydimethylsiloxane. The lenses achieve an NA in the range of 1.25. The principle of compound lens design is used to make the first compound solid immersion lens, which is corrected for higher light gathering ability and has a calculated NA=1.32.

Abstract: A method of fabricating an elastomeric structure, comprising: forming a first elastomeric layer on top of a first micromachined mold, the first micromachined mold having a first raised protrusion which forms a first recess extending along a bottom surface of the first elastomeric layer; forming a second elastomeric layer on top of a second micromachined mold, the second micromachined mold having a second raised protrusion which forms a second recess extending along a bottom surface of the second elastomeric layer; bonding the bottom surface of the second elastomeric layer onto a top surface of the first elastomeric layer such that a control channel forms in the second recess between the first and second elastomeric layers; and positioning the first elastomeric layer on top of a planar substrate such that a flow channel forms in the first recess between the first elastomeric layer and the planar substrate.

Abstract: Microfabricated lenses, e.g., solid immersion lens (SIL) structures, are provided along with techniques for constructing these lens structures, as well as selected applications of such lens structures.

Abstract: The present invention provides microfluidic devices and methods using the same in various types of thermal cycling reactions. Certaom devices include a rotary microfluidic channel and a plurality of temperature regions at different locations along the rotary microfluidic channel at which temperature is regulated. Solution can be repeatedly passed through the temperature regions such that the solution is exposed to different temperatures. Other microfluidic devices include an array of reaction chambers formed by intersecting vertical and horizontal flow channels, with the ability to regulate temperature at the reaction chambers. The microfluidic devices can be used to conduct a number of different analyses, including various primer extension reactions and nucleic acid amplification reactions.