18234 results about "Centrifugation" patented technology

Blood plasma of pregnant women contains fetal and (generally>90%) maternal circulatory extracellular DNA. Most of said fetal DNA contains ≦500 base pairs, said maternal DNA having a greater size. Separation of circulatory extracellular DNA of <500 base pairs results in separation of fetal from maternal DNA. A fraction of a blood plasma or serum sample of a pregnant woman containing, due to size separation (e.g. by chromatography, density gradient centrifugation or nanotechnological methods), extracellular DNA substantially comprising ≦500 base pairs is useful for non-invasive detection of fetal genetic traits (including the fetal RhD gene in pregnancies at risk for HDN; fetal Y chromosome-specific sequences in pregnancies at risk for X chromosome-linked disorders; chromosomal aberrations; hereditary Mendelian genetic disorders and corresponding genetic markers; and traits decisive for paternity determination) by e.g. PCR, ligand chain reaction or probe hybridization techniques, or nucleic acid arrays.

A vacuum cleaner includes a cleaner body, a suction brush, through which air and contaminants are drawn in, and a cyclone type dust collecting device. The cleaner body has a motor driving chamber and a dust collecting chamber in communication with the motor driving chamber. The cyclone type dust collecting device is mounted in the dust collecting chamber and separates by centrifugal force the contaminants from the air. The cyclone type dust collecting device includes a hollow cylindrical cyclone body having an open top, a closed bottom, and a contaminant outlet. The open top allows air and contaminants into the cyclone body, where the contaminants are separated from the air by centrifugation. The contaminants are then discharged from the cyclone body through the contaminant outlet. The cyclone type dust collecting device further includes a contaminant receptacle for collecting the contaminants discharged through the contaminant outlet, a base member hingedly connected to the contaminant receptacle, and a cover for covering the top of the cyclone body. The cover has an air inlet passage, through which air and contaminants drawn in through the suction brush enter into the cyclone body, an air outlet passage, through which the air is discharged from the cyclone body, and a contaminant separating grill. The grill extends downward from the air outlet passage into the cyclone body and has a plurality of fine holes.

The invention provides exemplary systems, methods, and apparatus for distinctly allocating liquids containing chemical compositions or compounds to known locations in an organized manner so that assays may be performed on the compositions, or so that the chemical compositions may be combined with other distinct chemical compositions or reagents prior to evaluation. In an exemplary embodiment, the invention includes a multiwell plate for handling articles such as resin beads suspended in a liquid. The plate comprises a plurality of wells. The wells in turn have a capillary hole that is adapted to (i) retain articles in the well, and (ii) retain liquid in the well while the liquid is not subjected to extrinsic forces, such as centrifugation or vacuum.

A device and method is provided for separating heavier and lighter fractions of a fluid sample. The device includes a plurality of constituents comprising a container and a composite element in the container. The composite element is a separator comprising at least two components and more particularly an elastic portion and a plug member. A fluid sample is delivered to the container and the device is subjected to centrifugation whereby the centrifugal load causes the elastic portion of the separator to deform so that the separator migrates into the fluid sample and stabilizes between the heavier and lighter fractions of the fluid sample. The elastic portion of the separator will resiliently return to its initial configuration upon termination of the centrifugal load such that the elastic portion sealingly engages the container and separates the heavier and lighter fractions of the fluid sample.

The present invention relates to moving microorganisms to a surface, where they are grown in the presence and absence of antimicrobials, and by monitoring the growth of the microorganisms over time in the two conditions, their susceptibility to the antimicrobials can be determined. The microorganisms can be moved to the surface through electrophoresis, centrifugation or filtration. When the movement involves electrophoresis, the presence of oxidizing and reducing reagents lowers the voltage at which electrophoretic force can be generated and allows a broader range of means by which the target can be detected. Monitoring can comprise optical detection, and most conveniently includes the detection of individual microorganisms. The microorganisms can be stained in order to give information about their response to antimicrobials.

The invention relates generally to methods of monitoring and controlling the processing of blood and blood samples, particularly the separation of blood and blood samples into its components. In one aspect, the invention relates to optical methods, devices and device components for measuring two-dimensional distributions of transmitted light intensities, scattered light intensities or both from a separation chamber of a density centrifuge. In embodiment, two-dimensional distributions of transmitted light intensities, scattered light intensities or both measured by the methods of the present invention comprise images of a separation chamber or component thereof, such as an optical cell of a separation chamber. In another aspect, the present invention relates to multifunctional monitoring and control systems for blood processing, particularly blood processing via density centrifugation. Feedback control systems are provided wherein two-dimensional distributions of transmitted light intensities, scattered light intensities or both are measured, processed in real time and are used as the basis of output signals for controlling blood processing. In another aspect, optical cells and methods of using optical cells for monitoring and control blood processing are provided.

A device for separating and isolating components of a biological fluid comprising a container for containing the fluid to be processed, a tube cap assembly for closing the container while providing filling and extraction communication therewith, a float assembly disposed within the container for funneling and controlling biological fluid flow into an inverted domed shaped isolation chamber within the float and controlling the biological fluid flow out of the isolation chamber for effecting an encapsulation or a sealed isolation of at least one component or fraction of the biological fluid flow within the isolation chamber during a centrifugation process. The device further comprising a flexible tube for connecting an extraction passageway disposed within the float assembly and an extraction valve of the tube cap assembly for allowing extraction of at least the one component or fraction encapsulated or isolated within the chamber.

The present invention recognizes that diagnosis and prognosis of many conditions can depend on the enrichment of rare cells, especially tumor cells, from a complex fluid sample such as a blood sample. In particular, the present invention is directed to methods and compositions for detecting a non-hematopoietic cell, e.g., a non-hematopoietic tumor cell, in a blood sample via, inter alia, removing red blood cells (RBCs) from a blood sample using a non-centrifugation procedure, removing white blood cells (WBCs) from said blood sample to enrich a non-hematopoietic cell, if any, from said blood sample; and assessing the presence, absence and/or amount of said enriched non-hematopoietic cell.

A scanning method for scanning samples of biological cells using optical tomography includes preparing, acquiring, reconstructing and viewing three-dimensional images of cell samples. Concentration and enrichment of the cell sample follows. The cell sample is stained. Cells are isolated from the cell sample and purified. A cell/solvent mixture is injected into a gel by centrifugation. A cell/gel mixture is injected into a capillary tube until a cell appears centered in a field of view using a step flow method. An optical imaging system, such as a fixed or variable motion optical tomography system acquires a projection image. The sample is rotated about a tube axis to generate additional projections. Once image acquisition is completed, the acquired shawdowgrams or image projections are corrected for errors. A computer or other equivalent processor is used to compute filtered backprojection information for 3D reconstruction.

A platelet collection device comprising a centrifugal spin-separator container with a cavity having a longitudinal inner surface. A float in the cavity has a base, a platelet collection surface above the base, an outer surface. The float density is below the density of erythrocytes and above the density of plasma. The platelet collection surface has a position on the float which places it below the level of platelets when the float is suspended in separated blood. During centrifugation, a layer of platelets or buffy coat collects closely adjacent the platelet collection surface. Platelets are then removed from the platelet collection surface. Movement of a float having a density greater than whole blood through the sedimenting erythrocytes releases entrapped platelets, increasing the platelet yield.

The present invention discloses a natural fruit and vegetable ferment beverage, and a preparation method thereof. The preparation method for the ferment beverage comprises: adding freshly-squeezed fruit and vegetable juice to marine fish skin collagen peptide; adopting the resulting mixture as a fermentation substrate; carrying out dilution, slurry mixing and sterilization, and then adopting a direct vat and freeze-dried type lactic acid starter to carry out fermentation; stopping the fermentation after 7-11 days until the pH value is 4.3; adding a supplementary feed and carrying out sterilization; then adding high-activity dried yeast to carry out fermentation; stopping the fermentation after 5-7 days until the pH value is 4.0; after storing the fermentation broth at the low temperature, carrying out homogenization, concentration, centrifugation, blending, sterilization and bulking to finally prepare the novel natural fruit and vegetable ferment beverage. According to the ferment beverage of the present invention, the stepwise fermentation is adopted for the freshly-squeezed fruit and vegetable juice by using the lactic acid bacteria and the yeast; the marine fish skin collagen peptide is added to promote the growth and the metabolism of fermentation bacteria, such that metabolic products of nutritional ingredients in the natural fruits and vegetables are rich so as to provide a beneficial nutrition and health effect.

The invention belongs to the technical field of membrane preparation and water purification and discloses a high-performance two-dimensional layered Ti3C2-MXene membrane, a preparation method thereof and an application of the Ti3C2-MXene membrane in water treatment. The method comprises steps as follows: (1), Ti3AlC2 powder and an HF solution are mixed, stirred for a reaction, centrifugally washed and dried, and Ti3C2 powder is obtained; (2), the Ti3C2 powder and a solvent are mixed, stirred for the reaction, washed and dried, and treated powder is obtained; (3), the treated powder is dissolved in the solvent and subjected to ultrasonic treatment and centrifugation, a liquid supernatant is taken and dried, and a two-dimensional nanosheet is obtained; (4), a solution is prepared from the two-dimensional nanosheet and deposited on a porous substrate with a nano self-assembly technology, and the high-performance two-dimensional layered Ti3C2-MXene membrane is obtained. The membrane has ultrahigh water flux, higher selectivity and good mechanical property and stability; the method is simple, low in energy consumption and cost, good in repeatability and wide in applicability.

Protein concentrates and protein isolates, in addition to processes for the production of protein concentrates and protein isolates, are disclosed. In particular, the disclosure relates to the removal of fiber from macroalgae and/or microalgae using low g-force centrifugation.

The invention discloses a preparation method of a graphene material. The preparation method comprises the following steps of: with graphite carbon as a raw material, adding potassium hypermanganate and concentrated sulfuric acid in batches in different stages to control an oxidation process of graphite; adjusting the pH value of the oxidized solution to obtain graphene oxide colloidal dispersing solutions (GOS) with different concentrations; dropwise adding the GOS on the surface of a carrier or spreading out the GOS on a non-intersolubility liquid/liquid interface and drawing into a grapheneoxide thin-film (GOF); carrying out high-speed centrifugation and drying treatment on the GOS to obtain graphene oxide solid powder (GOP); reducing the GOS by selecting an appropriate reducing agent,and centrifugally drying to obtain reduced graphene solid powder (GRP); dispersing a proper amount of GRP in an organic solvent to prepare a reduced graphene oxide colloidal dispersing solution (GRS); and dropwise adding the GRS on the surface of the carrier or spreading out on the non-intersolubility liquid/liquid interface and drawing into the reduced graphene thin-film (GRF). Various graphene materials prepared by the invention are easy to mutually transform; and the concentration of the colloidal solution and the thickness of the thin-film can be controlled in a certain range.

A tube and float system for use in separation and axial expansion of the buffy coat is provided. The system includes a transparent, or semi-transparent, flexible sample tube and a rigid separator float having a specific gravity intermediate that of red blood cells and plasma. The sample tube has an elongated sidewall having a first cross-sectional inner diameter. The float consists of a main body portion and one or more support members protruding from the main body portion to engage and support the sidewall of the sample tube. The main body portion and the support members of the float have a cross-sectional diameter less than that of the first cross-sectional inner diameter of the tube when the sample tube is expanded, such as by centrifugation. The main body portion of the float together with an axially aligned portion of the sidewall define an annular volume therebetween. The support members protruding from the main body portion of the float traverse said annular volume to produce one or more analysis areas. During centrifugation, the centrifugal force enlarges the diameter of the tube to permit density-based axial movement of the float in the tube. Thereafter, the centrifugal force is reduced to cause the tube sidewall to return to its first diameter, thereby capturing the float and trapping the buffy coat constituents in the analysis area. The buffy coat constituents can then be evaluated or measured.

A process for the fractionation of valuable fractions from cereal brans (e.g. wheat, barley and oat brans, and rice polish) is described. In particular, this invention describes a two step process, in which the said bran is first subjected to a combination of enzymatic treatment and wet milling, followed by sequential centrifugation and ultrafiltration, which aims at physically separating the main bran factions, i.e. insoluble phase (pericarp and aleurone layer), germ-rich fraction, residual endosperm fraction and soluble sugars. A second step consists of fractionating cereal brans substantially free of soluble compounds, hence insoluble phase from the above-mentioned first step, by enzymatic treatment with xylanases and/or beta-glucanase and wet milling, followed by sequential centrifugation and ultrafiltration, which aims at physically separating the main fractions, i.e. insoluble phase (remaining cell wall components), protein-rich fraction, soluble hemicellulose and oligosaccharide, and therefore maximizes the extraction rate of valuable cell wall components and aleurone cells from previously cleaned bran.

A flexible automated apparatus for isolating and purifying viruses, proteins and peptides of interest from a plant material is disclosed, the apparatus being applicable for large scale purification and isolation of such substances from plant material. The flexible automated apparatus provides an efficient apparatus for isolating viruses, proteins and peptides of interest with little waste material. The automated apparatus for isolating viruses, proteins and peptides of interest includes a grinding apparatus for homogenizing a plant to produce a green juice, a means for adjusting the pH of and heating the green juice, a means for separating the target species, either virus or protein/peptide, from other components of the green juice by one or more cycles of centrifugation, resuspension, and ultrafiltration, and finally purifying virus particles by such procedure as PEG-precipitation or purifying proteins and peptides by such procedures as chromatography and/or salt precipitation.

The invention relates to a Puer tea extract, a preparation method and application. The Puer tea extract contains effective ingredients of tea polyphenol, tea Polysaccharide, theabrownine, caffeine and the like the content of which are high, and can obviously lower blood sugar. The preparation method can effectively convert and dissolve out the effective ingredients. The process route can assure clarity after the cold water of a finished product is dissolved, lowers the late centrifugation workload, has low cost and stable and controllable quality and is industrial.