432 results about "Chemoselectivity" patented technology

A method and a device for detecting an analyte, including a substrate having a chemically selective surface; and a fluidic system disposed on the substrate, the manifold having at least one fluid path in communication with at least a discrete region of the surface, wherein the one fluid path and the discrete region together define a contained sample region on the surface. The fluidic system has a removable portion, wherein the removal of the removable portion of the fluidic system renders the discrete region directly interrogatable by a surface-based analytical tool.

The present invention features a chemoselective ligation reaction that can be carried out under physiological conditions. In general, the invention involves condensation of a specifically engineered phosphine, which can provide for formation of an amide bond between the two reactive partners resulting in a final product comprising a phosphine moiety, or which can be engineered to comprise a cleavable linker so that a substituent of the phosphine is transferred to the azide, releasing an oxidized phosphine byproduct and producing a native amide bond in the final product. The selectivity of the reaction and its compatibility with aqueous environments provides for its application in vivo (e.g., on the cell surface or intracellularly) and in vitro (e.g., synthesis of peptides and other polymers, production of modified (e.g., labeled) amino acids).

A microscale cylindrical ion trap, having an inner radius of order one micron, can be fabricated using surface micromachining techniques and materials known to the integrated circuits manufacturing and microelectromechanical systems industries. Micromachining methods enable batch fabrication, reduced manufacturing costs, dimensional and positional precision, and monolithic integration of massive arrays of ion traps with microscale ion generation and detection devices. Massive arraying enables the microscale cylindrical ion trap to retain the resolution, sensitivity, and mass range advantages necessary for high chemical selectivity. The microscale CIT has a reduced ion mean free path, allowing operation at higher pressures with less expensive and less bulky vacuum pumping system, and with lower battery power than conventional- and miniature-sized ion traps. The reduced electrode voltage enables integration of the microscale cylindrical ion trap with on-chip integrated circuit-based rf operation and detection electronics (i.e., cell phone electronics). Therefore, the full performance advantages of microscale cylindrical ion traps can be realized in truly field portable, handheld microanalysis systems.

A composite layer of a sorbent, chemoselective, non-electrically-conducting polymer and nano-particles of an electrically conducting material dispersed throughout the polymer is formed on a substrate by pulsed laser deposition, matrix assisted pulsed laser evaporation or matrix assisted pulsed laser evaporation direct writing.

A sensor instrument system for detecting and identifying analytes in fluids of a region comprising a local sensor instrument and remote central station. The instrument is comprised of a core technology employing a single sensor having two electrodes operated by an electrical frequency sweeping to generate two sets of patterned electrical information from a single measurement, a data transmission module and a GPS receiver module. The central station connects to a network means connected to a plurality of local receiving sites equipped with including the respective transceivers, so that the local analyte electrical information and geographic position information transmitted by the instrument can be wirelessly and remotely received and processed by the central station. The core technology is further comprised of a reference sensor for eliminating background influence, a temperature programming to control adsorption and desorption of analytes, and usage of all kinds of adsorbent materials having chemical selectivity including the hydrogen selectivity to enhance detection and identification of analytes in fluids.

A change in mass of a microbridge in a mass sensor can be sensed by applying a time-varying amplitude modulated electrostatic force to excite the microbridge into resonance at the frequency of amplitude modulation. An optical energy is then transmitted at a wavelength close to a resonant wavelength of a Fabry-Perot microcavity, which is formed by etching a movable reflective mirror into a region of the microbridge and by etching a fixed reflective minor in a region spaced apart from the microbridge. The two mirrors are interconnected by an optical waveguide. The movable mirror and fixed mirror reflect the optical energy to a receiver, and a change in the Fabry-Perot microcavity's reflectivity is interferometrically determined. The change in reflectivity indicates a change in the microbridge's resonant frequency due to increased mass of the microbridge resulting from sorption of a target chemical by a layer of chemoselective material deposited on the microbridge.

A hydrogel layer is applied to a substrate advantageously when the layer is formed in situ, using a polymeric or copolymeric precursor that includes, respectively, monomer subunits that have a photocrosslinkable functionality and monomer subunits that have a chemically selective functionality for binding a biomolecular analyte, such as a protein. A hydrogel-coated substrate thus obtained is particularly useful as a probe for mass spectroscopic analysis, including SELDI analysis. Hydrogel particles also can be used for SELDI analysis.

The invention describes a method for the selective dry etching of tantalum and tantalum nitride films. Tantalum nitride layers (30) are often used in semiconductor manufacturing. The semiconductor substrate is exposed to a reducing plasma chemistry which passivates any exposed copper (40). The tantalum nitride films are selectively removed using an oxidizing plasma chemistry.

A sensor instrument system and a method for detecting and identifying analytes in fluids of a region comprising a local sensor instrument and remote central station are disclosed. The instrument is comprised of a core technology employing a single sensor having two electrodes operated by an electrical frequency sweeping to generate two sets of patterned electrical information from a single measurement, a data transmission module and a GPS receiver module. The central station connects to a network means connected to a plurality of local receiving sites equipped with including the respective transceivers, so that the local analyte electrical information and geographic position information transmitted by the instrument can be wirelessly and remotely received and processed by the central station. The core technology is further comprised of a reference sensor for eliminating background influence, a temperature programming to control adsorption and desorption of analytes, and usage of all kinds of adsorbent materials having chemical selectivity including the hydrogen selectivity to enhance detection and identification of analytes in fluids.

The invention discloses a method for preparing picolinic acid through electro-catalysis selective dechloridation of chloropicolinicacid. According to the method, the chloropicolinicacid is added into a water solution for supporting an electrolyte or a mixed water solution for supporting the electrolyte and organic solvent, so that electrolytic reaction liquid is obtained, an electrolytic reaction is conducted in an electrolytic bath with a precious metal modified conducting material used as the cathode and a chemical inertness conducting material used as the anode, and accordingly the picolinic acid shown as the formula (II) is obtained. By the adoption of the method, the chloropicolinicacid or a mixture of the chloropicolinicacid can be reduced into the picolinic acid in high chemoselectivity, high efficiency and high yield modes, the problem that by-products cannot be handled easily in an existing synthetic technique of 3,6-clopyralid and 4-amino-3,6-clopyralid can be solved, and picolinic acid and 4-aminopyridine carboxylic acid products with high additional values further can be obtained.

The invention relates to a chemical sensor comprising a sensor film formed of a nanoparticle network in which the nanoparticles are interlinked by functionalized dendrimer molecules. The dendrimers support an efficient uptake of analyte molecules by the film material and therefore enable a high sensitivity of the sensor. In addition, the chemical nature of the dendrimers strongly determines the chemical selectivity of the sensor device. By cross-linking the components of the sensitive material the sensor displays a good mechanical stability.

The invention relates to a decarboxylation and fluorination method for carboxylic acid. According to the method, fatty acid RCOOH, monovalent silver salt catalyst and fluorinated reagent Selectfluor or hexafluorophosphate derivative thereof are reacted in a solvent at the temperature of between room temperature and 80 DEG C to obtain RF; and by adopting the method, the carboxylic acid is efficiently converted into corresponding decarboxylated and fluorinated product in an aqueous phase. The method is mild in reaction conditions and easy to operate, has good chemical selectivity and functional group compatibility, and is a very practical sp<3> carbon-fluorine bond synthesizing method.

A compact, portable or handheld device for measurement of breath VOCs such as acetone is described, which incorporates a flow measurement sensor, a mini preconcentrator unit and an spectroscopy unit, such as a cavity-enhanced absorption spectrometer. The preconcentrator includes a chemically selective material to trap VOCs, which is supported on a metal foam. The apparatus is suitable for measuring sub ppm levels of breath VOCs such as acetone and for tracking blood ketone levels.

The present invention relates to a multisensor array for detection of analytes in the gas phase or in the liquid phase, comprising at least two different chemo-selective compounds represented by the general formula (I) wherein the hetero atoms X¹-X⁴ and the substituents R¹-R⁴ are defined in the specification and the dashed bonds represent independently of each other either a single bond or a double bond. Said chemo-selective compounds are capable of individually changing physicochemical properties when exposed to analytes or analyte mixtures and these changes can be detected by a transducer or an array of transducers. The present invention does also relate to the use of at least two different chemo-selective compounds in a sensor array, a method for preparation of such sensor arrays and the use of said sensor arrays. Furthermore the present invention relates to methods for detecting and identifying analytes or mixtures thereof in the gas phase or in the liquid phase.

A method of forming a compound such as a polysaccharide sweetener compound is obtained via a process of cycloelimination of a macromolecule, for example, a glycoside, chemoselective promiscuous ligation of a first component constituent such as a constituent disaccharide fraction derived from the macromolecule with a second component such as a base monosaccharide, such as fructose, and cycloaddition of the base monosaccharide with a the constituent disaccharide fraction. Subsequent addition of fortifiers such as vitamins and minerals may be accomplished via baric processing to effect cross-linking or cross-bonding with the polysaccharide sweetener compound. A process for manufacturing polysaccharide sweetener compounds is provided and permits baric, electromagnetic, and thermal processing, at low temperatures, to effect the cycloelimination, chemoselective promiscuous ligation, and cycloaddition reactions. A method for selecting base and adjunct components for the manufacture of a polysaccharide sweetener compound having an equivalent functionality as a natural sweetener and/or derivative thereof as required for a specific food processing application is presented.

Molecules having potential biological activity, particularly peptoids, that are conjugated to solid phase supports, spacer groups, and/or ligation moieties, and methods of their preparation, are described. In some instances, the molecules of the invention are made entirely by solid phase synthesis. In other instances, the spacer groups are hydrophilic and compositions containing them, and to solid phase synthesis of varied structure peptoids using chemoselective ligation moieties.