2224 results about "Analytic chemistry" patented technology

Random arrays of single molecules are provided for carrying out large scale analyses, particularly of biomolecules, such as genomic DNA, cDNAs, proteins, and the like. In one aspect, arrays of the invention comprise concatemers of DNA fragments that are randomly disposed on a regular array of discrete spaced apart regions, such that substantially all such regions contain no more than a single concatemer. Preferably, such regions have areas substantially less than 1 μm2 and have nearest neighbor distances that permit optical resolution of on the order of 109 single molecules per cm2. Many analytical chemistries can be applied to random arrays of the invention, including sequencing by hybridization chemistries, sequencing by synthesis chemistries, SNP detection chemistries, and the like, to greatly expand the scale and potential applications of such techniques.

A microsphere-based analytic chemistry system and method for making the same is disclosed in which microspheres or particles carrying bioactive agents may be combined randomly or in ordered fashion and dispersed on a substrate to form an array while maintaining the ability to identify the location of bioactive agents and particles within the array using an optically interrogatable, optical signature encoding scheme. A wide variety of modified substrates may be employed which provide either discrete or non-discrete sites for accommodating the microspheres in either random or patterned distributions. The substrates may be constructed from a variety of materials to form either two-dimensional or three-dimensional configurations. In a preferred embodiment, a modified fiber optic bundle or array is employed as a substrate to produce a high density array. The disclosed system and method have utility for detecting target analytes and screening large libraries of bioactive agents.

Self-encoding microspheres having distinct characteristic optical response signatures to specific target analytes may be mixed together while the ability is retained to identify the sensor type and location of each sensor in a random dispersion of large numbers of such sensors in a sensor array using an optically interrogatable encoding scheme, resulting in a microsphere-based analytic chemistry system. Individual microsphere sensors are disposed in microwells at a distal end of a fiber bundle and are optically coupled to discrete fibers or groups of fibers within the bundle to form an optical fiber bundle sensor. The identities of the individual sensors in the array are self-encoded by exposing the array to a reference analyte while illuminating the array with excitation light energy. A single sensor array may carry thousands of discrete sensing elements whose combined signal provides for substantial improvements in sensor detection limits, response times and signal-to-noise ratios.

A microsphere-based analytic chemistry system and method for making the same is disclosed in which microspheres or particles carrying bioactive agents may be combined randomly or in ordered fashion and dispersed on a substrate to form an array while maintaining the ability to identify the location of bioactive agents and particles within the array using an optically interrogatable, optical signature encoding scheme. A wide variety of modified substrates may be employed which provide either discrete or non-discrete sites for accommodating the microspheres in either random or patterned distributions. The substrates may be constructed from a variety of materials to form either two-dimensional or three-dimensional configurations. In a preferred embodiment, a modified fiber optic bundle or array is employed as a substrate to produce a high density array. The disclosed system and method have utility for detecting target analytes and screening large libraries of bioactive agents.

This invention pertains to chemometric methods for the analysis of chemical, biochemical, and biological data, for example, spectral data, for example, nuclear magnetic resonance (NMR) spectra, and their applications, including, e.g., classification, diagnosis, prognosis.

A system for detecting and analyzing chemical and biological aerosols. A beam of radiation is used to radiate a target cloud including the aerosol. The radiation energy that is absorbed by the cloud is thermalized by collisional energy transfer between the molecules that absorb the radiation to generate heat. The wavelength of the electromagnetic radiation is selected to be in resonance with the absorption lines of water or oxygen molecules in the cloud, or to be in resonance with absorption lines of known target molecules in the cloud to generate the heat. An increase in the cloud temperature increases the emission intensity of the molecules against the background, resulting in improved detection of the target molecules in the aerosol. A tracking telescope collects the thermal emissions generated by the radiation beam. A spectrometer receives the emissions from the cloud and generates an emission spectrum.

This invention pertains to chemometric methods for the analysis of chemical, biochemical, and biological data, for example, spectral data, for example, nuclear magnetic resonance (NMR) spectra, and their applications, including, e.g., classification, diagnosis, prognosis, etc., especially in the context of bone disorders, e.g., conditions associated with low bone mineral density, e.g., osteoporosis.

Ultraporous sol gel monoliths and methods for preparing the same are provided, having superior flow characteristics for chromatography and analytical chemistry applications. The methods for forming an ultra porous sol-gel monolith include (a) forming a solution comprising a porogen, a matrix dissolving catalyst and a sol gel precursor; (b) allowing the solution to form a gel; and (c) drying the gel at an elevated temperature. The ultraporous sol gel monoliths are characterized by a porosity of up to about 97%, a BET surface area of at least about 50 m2 / g and substantially no micropores.

The invention relates to the fields of analytical chemistry and food safety, in particular to a method for detecting the residual quantity of multiple alkaline drugs in animal derived food. Based on the vortex mixed extracting of acetonitrile, isopropanol and citric acid buffer solutions, the purification of a hydrophilic polystyrene-divinylbenzene solid phase extraction column and a cation exchange solid phase extraction column and the liquid phase chromatography-mass spectra determination, the method can detect the residual quantity of multiple alkaline drugs in pork, pork liver, eggs, shrimps and milk, such as beta-receptor agonists,sulfonamides, benzodiazepines, nitroimidazoles, benzimidazoles and triphenylmethanes. The method has the advantages of simple operation, fast and accurate detection and high efficiency.

The invention discloses a Gaussian process regression-based method for predicting state of health (SOH) of lithium batteries, relates to a method for predicting the SOH of the lithium batteries, belongs to the fields of electrochemistry and analytic chemistry and aims at the problem that the traditional lithium batteries are bad in health condition prediction adaptability. The method provided by the invention is realized according to the following steps of: I. drawing a relation curve of the SOH of a lithium battery and a charge-discharge period; II, selecting a covariance function according to a degenerated curve with a regeneration phenomenon and a constraint condition; III, carrying out iteration according to a conjugate gradient method, then determining the optimal value of a hyper-parameter and bringing initial value thereof into prior distribution; IV, obtaining posterior distribution according to the prior part; V, obtaining the mean value and variance of predicted output f' without Gaussian white noise; and VI, together bringing the practically predicted SOH of the battery and the predicted SOH obtained in the step V into training data y to obtain the f', then determining the prediction confidence interval and predicting the SOH of the lithium battery. The method provided by the invention is used for detecting lithium batteries.

A method is described for providing rapid on-line analyses of chemical compositions such as chemical process streams, utilizing near-infrared (NIR) spectroscopy in combination with chemometrics. In the method, for each type of analysis to be conducted, a database is provided by analyzing a series of samples using standard laboratory analytical procedures, utilizing the results as reference values to establish quantitative calibration models from NIR spectroscopy using chemometric techniques and storing this information in a computer database. An NIR spectroscopic system is also provided comprising a transflectance or a transmittance probe coupled via fiber-optic cables to a stable white light source and a spectrograph. The probe is inserted into a test sample or chemical process stream to be analyzed, a stable white light of selected wavelength range is beamed to the probe and the spectra obtained on the spectrograph are recorded. Finally the spectra obtained are correlated to the reference data stored in the computer to obtain a rapid measurement of the analysis desired.

A system for modeling, simulating and analyzing chemical and biochemical reactions includes a modeling environment for constructing a model of a chemical or biochemical system comprising a plurality of chemical reactions. The system also includes a simulation engine accepting as input said constructed model of the chemical or biochemical system and generating as output an expected result. The modeling environment includes a block diagram explorer for displaying a block diagram in a graphical user interface describing the system as a hierarchical network of interconnected blocks. Each block represents a species participating one of the chemical reactions or one of said chemical reactions in the system. The block diagram explorer allows for a user to manipulate and modify the graphical parameters of the block diagram representation to provide insight into the functionality and operation of the system being modeled.

A system for detecting and analyzing chemical and biological materials in a sample. The system includes a spectrometer for passively receiving emissions from the sample in the terahertz frequency band to detect the materials therein. A telescope or other device can be used to confine the field-of-view of the spectrometer. A cold surface is positioned filling the field-of-view of the spectrometer at an opposite side of the sample from the spectrometer. The cold surface provides a low temperature background relative to the sample so as to reduce the background emission and enhance the detection of the emission from the sample.

Methods and assay systems for analyzing effects of chemical and cellular agents on brain cell neurogenesis in vivo, comprising administering an agent to a test animal and determining responses of cells of brain marrow tissues, including irradiated brain marrow tissue depleted of neurogenic stems cells, and cells in brain marrow-derived neurospheres cultured in vitro.

The invention relates to a micro flow control chip in the leading edge field of analytical chemistry, which has the characters of small volume, fast analysis. Although micro flow control chip integrated with laser evoked fluorescence detection can do 384 channels high-pass measuring, it isn't reported multichannel electric chemistry measuring from now on. The invention provides a multichannel micro flow control chip, which adopts high molecular material polymethyl methacryate, and fabricates monocrystalline silicon core by using the technology of photo etching and etching, and microchannel adopts hot-press method or polymerization. It integrals the measuring electric pole channel onto the chip. It can fill functional material into electric pole and control the distance of working electric pole and separating channel.

An integrated system for modeling, simulating and analyzing chemical and biochemical reactions includes a modeling environment for constructing a model of a chemical or biochemical reaction. The system also includes a simulation engine accepting as input said constructed model of the chemical or biochemical reaction and generating as output an expected result for a first chemical reaction using a first type of computational model and an expected result for a second chemical reaction using a second type of computational model. An analysis environment communicates with the simulation engine and displays the expected result

A system and method for sub-micron analysis of a chemical composition of a specimen are described. The method includes providing a specimen for evaluation and a thermal desorption probe, thermally desorbing an analyte from a target site of said specimen using the thermally active tip to form a gaseous analyte, ionizing the gaseous analyte to form an ionized analyte, and analyzing a chemical composition of the ionized analyte. The thermally desorbing step can include heating said thermally active tip to above 200° C., and positioning the target site and the thermally active tip such that the heating step forms the gaseous analyte. The thermal desorption probe can include a thermally active tip extending from a cantilever body and an apex of the thermally active tip can have a radius of 250 nm or less;

The invention belongs to the technical field of sample pretreatment in analytical chemistry and relates to a preparation method and use of a molecular imprinting-absorbing extraction stirring rod. The preparation process of the method comprises the following steps: sintering one end of a capillary glass tube serving as a substrate of the stirring rod, and subjecting to the sintered capillary glass tube to acid and alkali treatment and surface modification by a silylating agent respectively; performing the self-assembly of template molecules and bifunctional monomers in a polymer solvent, adding a crosslinker and an initiator in the solution, plugging the modified capillary glass tube into the solution; drawing the capillary glass tube out; repeatedly coating the capillary glass tube to a required thickness, and aging the coating; cutting a proper length of coated capillary glass tube, putting the length of coated capillary glass tube in a magnetic core, and sintering the capillary glass tube for end sealing; and eluting the template molecules. The molecular imprinting-absorbing extraction stirring rod prepared by the invention can selectively separate and enrich a trace amount of template molecules and analogues at the same time and is suitable for selectively separating, enriching and analyzing a trace amount of template molecules and analogues in complex samples in terms of organism, food and environment.

The invention relates to a method for simultaneously detecting three antibiotic residues including streptomycin, chlorampenicol and tetracycline based on nucleic acid aptamers and quantum dots and belongs to the technical field of analytical chemistry. Three-section complementary cDNA 1 sequences are designed and synthesized and are complemented with three antibiotic aptamers DNA sequences and are further complemented with respective capturing probe DNA sequences of three antibiotics and complementary cDNA 2 sequence part. The three cDNAs 1 are first hybridized with aptamer DNAs supplemented with each other to form double-stranded DNAs. When target antibiotics exist in a sample, the aptamer DNAs are combined with corresponding antibiotics as a priority to cause the double-stranded DNAs to be de-hybridized and release cDNAs 1. The free cDNAs 1 are combined with capturing probe DNAs modified on the surface of a gold electrode, and cDNAs 2 modified with three quantum dots are hybridized with the other end of each cDNA 1. The three quantum dots on the surface of the gold electrode generate dissolution volt-ampere peaks corresponding to the target antibiotics. The three antibiotics are detected by utilizing the relations of changes of peak current values and antibiotic concentration. The method is good in repeatability and stability and high in sensitivity and can be used for directly measuring the three antibiotic residues in samples such as milk.

An integrated system for modeling, simulating and analyzing chemical and biochemical reactions includes a modeling environment for constructing a model of a chemical or biochemical reaction. The system also includes a simulation engine accepting as input said constructed model of the chemical or biochemical reaction and generating as output an expected result. An analysis environment communicates with the simulation engine and displays the expected result.

The invention relates to a method for rapidly detecting the residuals of organophosphorus pesticides in vegetables by utilizing an Au nano-particle colorimetric method, which belongs to the technical field of analytical chemistry. The method provided by the invention comprises the following detection steps: preparation of Au nano-particles (AuNps); establishment of a method for detecting organophosphorus pesticides, actual sample detection and the like. The method provided by the invention can simply, rapidly and sensitively detect methamidophos in the organophosphorus pesticides according to the color change of an Au nano-particle system, has high sensitivity and provides convenience for further research, production, supervision and the like.

An integrated chromatography-immunoassay system for integrated chromatography-immunoassay system includes a chromatographic unit that receives labeled nano-structured probes comprising nano particles and antibodies attached to the nano particles, and a test membrane comprising coating antigens. The chromatographic unit allows the labeled nano-structured probes to diffuse there through and into the test membrane, wherein the antibodies on the nano particles are bound to the coating antigens. A laser device emits a laser light to illuminate the labeled nano-structured probes having the antibodies bound to the coating antigens on the test membrane. A spectral analyzer obtains a Raman spectrum from light scattered from the labeled nano-structured probes having the antibodies bound to the coating antigens on the test membrane, and to identify a spectral signature in the Raman spectrum associated with the antibody-antigen pair, which enables detection and identification of the antibody.

The invention relates to the field of analytical chemistry and food safety, and provides a high performance liquid chromatography detection method for residual quantity of multiple ultraviolet absorbents in cosmetics. A cosmetic sample of 0.4g is weighed and placed in a plastic centrifuge tube of 50 ml, sample extraction liquid of 20ml is added, after the cosmetic sample of 0.4g and the sample extraction liquid of 20ml are mixed for 2 minutes in a vortex mode, sonic oscillation extraction is carried out for 20 minutes, 8000 revolutions per minute centrifugation is carried out for 10 minutes and, and supernate is to be purified; and after test solutions sequentially pass through microfiltration membranes of 0.45 micrometer and 0.20 micrometer, a high performance liquid chromatograph is adopted to carry out qualitative determination and quantitative assay. The detection method has the advantages of being simple, fast, accurate, efficient, and the like, and can detect 12 ultraviolet absorbents at the same time. Technical indexes of detection minimum, the recovery rate, the degree of precision, and the like all meet relevant demands for ultraviolet absorbent detection in sun block cosmetics at home and abroad. The method is suitable for detection and monitoring of the ultraviolet absorbents in the sun block cosmetics, and has great significance on promoting of import and export trade of cosmetics of our country, ensuring of safety of the cosmetics, and guarantee of human body health.

The invention relates to a method for detecting bisphenol A and bisphenol AF in food, belonging to technical field of analytical chemistry determination method. With ionic liquid (1-butyl-3-methylimidazole hexafluorophosphate) as an extractant and TritonX-100 or acetone as an dispersant, ultrasonic oscillation is carried out to form emulsion; after centrifugal separation, extraction drops at the lower layer are directly subjected to HPLC (high performance liquid chromatography) quantitative analysis. The method disclosed by the invention has the advantages of simpleness in detection steps, easiness in operation, low detection limit and high enrichment multiple, greatly reduced detection cost. The method disclosed by the invention is a rapid, efficient and environmentally friendly pre-treatment technology and has a wider application prospect in the field of food analysis.

The invention relates to a preparation method and application of a formaldehyde fluorescent probe, and belongs to the technical field of analytical chemistry. The formaldehyde fluorescent probe is a ratio-type fluorescent probe with double emission bands. The excitation wavelength is 318 nm; and the fluorescence peak at 359nm decreases gradually with the increasing of the concentration of formaldehyde, and at the same time a new emission band is produced at 451 nm and the fluorescence peak gradually increases. The formaldehyde fluorescent probe can resist the interference of acetaldehyde, glyoxal, methylglyoxal, benzaldehyde, alanine, glycine, serine, arginine, cysteine, glutathione and glucose, has high detection accuracy, high sensitivity and strong anti-interference capability. In addition, the formaldehyde fluorescent probe of the invention can detect the formaldehyde in a biological sample (cell environment), realizes formaldehyde fluorescence imaging in living cell level, and has potential practical application value. The synthesis of the formaldehyde fluorescent probe only needs a one-step reaction, which is simple and high in yield.