Abstract: The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode waveguide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.

Abstract: The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode waveguide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.

Abstract: The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode waveguide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.

Abstract: A new technique for fabricating two-dimensional and three-dimensional fluid microchannels for molecular studies includes fabricating a monolithic unit using planar processing techniques adapted from semiconductor electronics fabrication. A fluid gap between a floor layer (12) and a ceiling layer (20) is provided by an intermediate patterned sacrificial layer (14) which is removed by a wet chemical etch. The process may be used to produce a structure such as a filter or artificial gel by using Electron beam lithography to define a square array of 100 nm holes (30) in the sacrificial layer. CVD silicon nitride (54) is applied over the sacrificial layer and enters the array of holes to produce closely spaced pillars. The sacrificial layer can be removed with a wet chemical etch through access holes in the ceiling layer, after which the access holes are sealed with VLTO silicon dioxide (64).

Abstract: A new technique for fabricating two-dimensional and three-dimensional fluid microchannels for molecular studies includes fabricating a monolithic unit using planar processing techniques adapted from semiconductor electronics fabrication. A fluid gap between a floor layer (12) and a ceiling layer (20) is provided by an intermediate patterned sacrificial layer (14) which is removed by a wet chemical etch. The process may be used to produce a structure such as a filter or artificial gel by using Electron beam lithography to define a square array of 100 nm holes (30) in the sacrificial layer. CVD silicon nitride (54) is applied over the sacrificial layer and enters the array of holes to produce closely spaced pillars. The sacrificial layer can be removed with a wet chemical etch trough access holes in the ceiling layer, after which the access holes are sealed with VLTO silicon dioxide (64).

Abstract: A three dimensional microfluidic device is formed by placing a membrane between two micropatterned chips. The membrane is positioned to cover the area where channels intersect. In one embodiment the membrane is porous. The chips are formed of plastic, and are thermally bonded under pressure. Reservoirs are formed on the chips at each end of each channel. The channels are created in the chip by use of an embossing master, such as a patterned silicon wafer. The reservoirs are formed by drilling. A hydraulic press is used to emboss both chips, and is also used to thermally bond the chips and membrane under pressure. The surfaces of the channels are oxidized, changing the surfaces from hydrophobic to hydrophilic.

Abstract: The present invention is directed to a method and an apparatus for analysis of an analyte. The method involves providing a zero-mode waveguide which includes a cladding surrounding a core where the cladding is configured to preclude propagation of electromagnetic energy of a frequency less than a cutoff frequency longitudinally through the core of the zero-mode waveguide. The analyte is positioned in the core of the zero-mode waveguide and is then subjected, in the core of the zero-mode waveguide, to activating electromagnetic radiation of a frequency less than the cut-off frequency under conditions effective to permit analysis of the analyte in an effective observation volume which is more compact than if the analysis were carried out in the absence of the zero-mode waveguide.

Abstract: Biomolecular photo-based patterning methods utilize avidin-biotin technology to immobilize functional proteins on the inner surface of silica glass tubes in desired patterns. The methods are useful for nanofluidic affinity biosensor/chromatography systems and on silicon dioxide substrates for biosensor applications. The resulting patterns are optimized based on the application. A zebra shaped pattern is utilized for an affinity chromatography system.

Abstract: A microfluidic device has features that reduce the speed of flow of higher speed diffusing molecules. The features are used to separate various components of a mixture in the microfluidic device. The channel is sized to ensure laminar flow of the mixture to promote only diffusive mixing of the components. Wells extend from the channel. Components having higher diffusing velocities are slowed by the wells as the mixture proceeds through the channel. The result is that slower speed diffusing components exit the channel prior to the lower speed diffusing components. The device is formed by use of photolithographic techniques or other techniques capable of forming such features.

Abstract: Separation of long molecules by length is obtained by forcing such molecules to traverse a boundary between a low free-energy region and a high free-energy region. In one embodiment, the high free-energy region is a dense pillar region or other structure formed on a semiconductor substrate. One or more membranes are used in further embodiments. The low free-energy region is a larger chamber formed adjacent the high free-energy region. A recoil phase allows longer molecules not fully driven into the high free-energy region to recoil into the low free-energy region. In a further variation, the high free-energy region is a membrane having nanoscale holes.

Abstract: Processes for purifying compounds are disclosed which include reacting (i) a mixture of at least one tocopherol compound or sterol compound, and an alcohol having from about 10 to 30 carbons with (i) one or more boron-containing compounds to form a second mixture of orthoborate esters, wherein the mole ratio of tocopherol, sterol and alcohol to boron is at least about 2.5:1; heating the second mixture to form a residue containing the orthoborate esters; contacting the residue with a compound capable of solvolyzing the orthoborate esters to form a third mixture including the boron-containing compound(s), the alcohol and the tocopherol and/or sterol compound(s); and recovering the tocopherol and/or sterol compound(s).

Abstract: Processes for purifying compounds are disclosed which include reacting (i) a mixture of at least one tocopherol compound or sterol compound, and an alcohol having from about 10 to 30 carbons with (ii) one or more boron-containing compounds to form a second mixture of orthoborate esters, wherein the mole ratio of tocopherol, sterol and alcohol to boron is at least about 2.5:1; heating the second mixture to form a residue containing the orthoborate esters; contacting the residue with a compound capable of solvolyzing the orthoborate esters to form a third mixture including the boron-containing compound(s), the alcohol and the tocopherol and/or sterol compound(s); and recovering the tocopherol and/or sterol compound(s).

Abstract: A new technique for fabricating two-dimensional and three-dimensional fluid microchannels for molecular studies includes fabricating a monolithic unit using planar processing techniques adapted from semiconductor electronics fabrication. A fluid gap between a floor layer (12) and a ceiling layer (20) is provided by an intermediate patterned sacrificial layer (14) which is removed by a wet chemical etch. The process may be used to produce a structure such as a filter or artificial gel by using Electron beam lithography to define a square array of 100 nm holes (30) in the sacrificial layer. CVD silicon nitride (54) is applied over the sacrificial layer and enters the array of holes to produce closely spaced pillars. The sacrificial layer can be removed with a wet chemical etch through access holes in the ceiling layer, after which the access holes are sealed with VLTO silicon dioxide (64).

Abstract: Carboxylic acids, particularly dicarboxylic acids, are separated from a fermentation broth by adjusting the pH of the fermentation broth to about 2.0 or below, and then heating the broth to a temperature sufficient to cause formation of three immiscible phases, one of which is an organic phase containing the carboxylic acids.

Abstract: Sterols are hydrogenated to stanols in the presence of hydrogenation catalysts in reduced amounts of organic solvent. Both alcohols and paraffin hydrocarbons and also mixtures of alcohols and paraffin hydrocarbons may be used as the solvent. By virtue of the reduced consumption of solvent and the high yield of hydrogenated sterol, the process is particularly suitable for the industrial production of stanols.

Abstract: A process for the preparation of a mixture of trimethylolpropane caprylate and trimethylolpropane caprate comprising the steps ofA) purifying a less than pure mixture of methyl caprylate and methyl caprate;B) reacting the purified mixture from step A) with trimethylolpropane to transesterify the purified mixture to produce a reaction mixture containing trimethylolpropane caprylate and trimethylolpropane caprate; andC) removing methanol and unreacted methyl caprylate and methyl caprate from the reaction mixture.

Abstract: This invention provides a process for preparing an oligomer of at least one polyunsaturated aliphatic C.sub.12-22 monocarboxylic acid ester in the presence of boron trifluoride resulting in a high yield or predominantly trimeric product which, upon hydrolysis, affords a high yield of polybasic, predominantly trimeric, acids. This invention further provides such a process with excellent recovery of the boron trifluoride.

Abstract: A process for recovering fatty materials, such as fatty acids and lower alkyl esters thereof, from supported nickel catalyst compositions is provided. For the process, the supported nickel catalyst composition, which may also contain non-nickel containing clays/earths, is extracted with a supercritical fluid, preferably supercritical carbon dioxide, to separate the fatty material from the supported nickel catalyst composition.

Abstract: A process is provided whereby the dimer fraction obtained from a boron trifluoride catalyzed oligomerization process is reacted with an .alpha.-olefin in the presence of a phosphoric acid-modified boron trifluoride catalyst to produce higher oligomeric products typically having viscosities (210.degree. F.) in the 4 to 8 centistoke range.