136 results about "Fluorescent tag" patented technology

A method and apparatus for use in a flow through assay process is disclosed. The method is characterised by a “pre-incubation step” in which the sample which is to be analysed, (typically for the presence of a particular protein), and a detection analyte (typically an antibody bound to colloidal gold or a fluorescent tag) which is known to bind to the particular protein may bind together for a desired period of time. This pre incubation step occurs before the mixture of sample and detection analyte come into contact with a capture analyte bound to a membrane. The provision of the pre-incubation step has the effect of both improving the sensitivity of the assay and reducing the volume of sample required for an assay. An apparatus for carrying out the method is disclosed defining a pre-incubation chamber for receiving the sample and detection analyte having a base defined by a membrane and a second membrane to which a capture analyte is bound. In one version the pre-incubation chamber is supported above the second membrane in one position but can be pushed into contact with the membrane carrying the capture analyte thus permitting fluid transfer from the incubation chamber through the capture membrane. In another version the membrane at the base of the incubation chamber is hydrophobic and its underside contacts the capture membrane and when a wetting agent is applied to the contents of the pre-incubation chamber fluid transfer occurs.

The present invention relates to a functionally integrated microanalytical system for performing fluorescence spectroscopy. A source of fluorescence-exciting radiation, typically a LED, is integrated onto a substrate along with a photodetector and, in some embodiments, an optical filter. A pixel-to-point laser lift-off process is used to effect this component integration. For those cases in which a filter is required, a thin film bandgap filter is typically used, such as CdS or CdSxSe1-x (0<x<1). A disposable microchannel containing the sample and its fluorescent tag is mounted onto the integrated assembly of LED, photodetector and (optionally) filter. This configuration of components allows the microchannel and sample to be readily removed and replaced, facilitating rapid analysis of multiple samples. Multiple LEDS, detectors and filters (if present) can also be integrated onto the same substrate, permitting multiple wavelength analysis of the sample to be performed concurrently.

Endotoxin, also known as lipopolysaccharides (LPS), is the major mediator of septic shock due to Gram-negative bacterial infection. Chemically synthesized S3 peptide, derived from Sushi3 domain of Factor C, which is the endotoxin-sensitive serine protease of the limulus coagulation cascade, binds and neutralizes LPS activity. Fluorescent tagged-S3 is shown to detect LPS-containing bacteria. For large-scale production of S3 and to mimic other pathogen-recognizing molecules, tandem multimers of the S3 gene were constructed and expressed in E. coli. Tetramer of S3 for example is shown to display an enhanced inhibitory effect on LPS-induced activities. An affinity matrix based on tetramer of S3 is also shown to be particularly efficient at removing LPS.

The present invention relates to a functionally integrated microanalytical system for performing fluorescence spectroscopy. A source of fluorescence-exciting radiation, typically a LED, is integrated onto a substrate along with a photodetector and, in some embodiments, an optical filter. A pixel-to-point laser lift-off process is used to effect this component integration. For those cases in which a filter is required, a thin film bandgap filter is typically used, such as CdS or CdSxSe1-x (0<x<1). A disposable microchannel containing the sample and its fluorescent tag is mounted onto the integrated assembly of LED, photodetector and (optionally) filter. This configuration of components allows the microchannel and sample to be readily removed and replaced, facilitating rapid analysis of multiple samples. Multiple LEDS, detectors and filters (if present) can also be integrated onto the same substrate, permitting multiple wavelength analysis of the sample to be performed concurrently.

The invention provides a new method for DNA sequencing called “natural sequencing by synthesis” (nSBS). According to the method, DNA that includes a desired sequence is synthesized using a dNTP mix with a small percentage of fluorescently-labeled nucleotides. The fluorescent label is cleavable. In contrast to previous methods that utilize 100% labeled nucleic acids, use of a small percentage of labeled nucleic acids minimizes the distortion of the natural structure of the extending DNA strand and the DNA polymerase. Using the disclosed methods with less than 10,000 copies of template DNA and 10% of the nucleotides labeled, long homopolymer stretches up to 20 bases can be sequenced with high accuracy and Q20 (with 99% accuracy) read lengths of up to 1,000 bases can be achieved. A Q20 read length of greater than 100 bases can potentially be achieved, even if the sequencing is performed with 1,000 copies of a template and 10% of the nucleotides labeled.

The present invention provides novel fluorescent compounds and covalent attachment chemistries which facilitate the use of these compounds as labels for ultrasensitive and quantitative fluorescent detection of low levels of biomolecules. In a preferred embodiment, the fluorescent labels of this invention are novel derivatives of the hydroxy-pyrene trisulphonic and disulphonic acids which may be used in any assay in which radioisotopes, colored dyes or other fluorescent molecules are currently used. Thus, for example, any assay using labeled antibodies, proteins, oligonucleotides or lipids, including fluorescent cell sorting, fluorescence microscopy (including dark-field microscopy), fluorescence polarization assays, ligand, receptor binding assays, receptor activation assays and diagnostic assays can benefit from use of the compounds disclosed herein.

A micromechanical actuator for sorting hematopoietic stem cells for use in cancer therapies. The actuator operates by diverting cells into one of a number of possible pathways fabricated in the fabrication substrate of the micromechanical actuator, when fluorescence is detected emanating from the cells. The fluorescence results from irradiating the cells with laser light, which excites a fluorescent tag attached to the cell. The micromechanical actuator thereby sorts the cells individually, with an operation rate of 3.3 kHz, however with the massively parallel 1024-fold device described herein, a throughput of 3.3 million events / second is achievable.

A method and apparatus for use in a flow through assay process is disclosed. The method is characterised by a “pre-incubation step” in which the sample which is to be analysed (typically for the presence of a particular protein), and a detection analyte (typically one or more antibodies bound to colloidal gold or a fluorescent tag) which is known to bind to the particular protein may bind together for a desired period of time. This pre-incubation step occurs before the mixture of sample and detection analyte come into contact with a capture analyte bound to a membrane. The provision of the pre-incubation step has the effect of both improving the sensitivity of the assay and reducing the volume of sample required for an assay. An apparatus for carrying out the method is disclosed defining a pre-incubation chamber for receiving the sample and detection analyte having a base defined by a membrane and a second membrane to which a capture analyte is bound. In one version the pre-incubation chamber is supported above the second membrane in one position but can be pushed into contact with the membrane carrying the capture analyte thus o permitting fluid transfer from the incubation chamber through the capture membrane. In another version the membrane at the base of the incubation chamber is hydrophobic and its underside contacts the capture membrane and when a wetting agent is applied to the contents of the pre-incubation chamber fluid transfer occurs.

This invention relates to a micromachined microfluidics diagnostic device that comprises one or multiple assaying channels each of which is comprised a sample port, a first valve, a reaction chamber, a second valve, a fluid ejector array, a third valve, a buffer chamber, a capture zone and a waste chamber. Each of these device components are interconnected through microfluidic channels. This invention further relates to the method of operating a micromachined microfluidic diagnostic device. The flow of fluid in the microchannels is regulated through micromachined valves. The reaction of sample analytes with fluorescent tags and detection antibodies in the reaction chamber are enhanced by the micromachined active mixer. By ejecting reaction mixture onto the capture zone through micromachined fluid ejector array, the fluorescent tagged analytes bind with capturing antiodies on capture zone. The fluid ejector array further ejects buffer fluid to wash away unbound fluorescent tags.

A method of inhibiting light-induced degradation of nucleic acids includes irradiating a portion of the nucleic acids in the presence of a detection solution comprising a polyphenolic compound. A method of detecting a nucleic acid having a fluorescent tag includes irradiating at least a portion of the nucleic acid with light of a suitable wavelength to induce a fluorescence emission and detecting the fluorescence emission. Optionally, the polyphenolic compound is gallic acid, a lower alkyl ester thereof, or mixtures thereof. A kit includes one or more nucleotides, an enzyme capable of catalyzing incorporation of the nucleotides into a nucleic acid strand and a polyphenolic compound suitable for preparing a detection solution.

Multimeric protected fluorescent reagents and their methods of synthesis are provided. The reagents are useful in various fluorescence-based analytical methods, including the analysis of highly multiplexed optical reactions in large numbers at high densities, such as single molecule real time nucleic acid sequencing reactions. The reagents contain fluorescent dye elements, that allow the compounds to be detected with high sensitivity at desirable wavelengths, binding elements, that allow the compounds to be recognized specifically by target biomolecules, and protective shield elements, that decrease undesirable contacts between the fluorescent dye elements and the bound target biomolecules and that therefore decrease photodamage of the bound target biomolecules by the fluorescent dye elements. The reagents also contain coupling elements connect monomeric compounds into multimeric forms, thereby increasing brightness.

The present invention belongs to the technical field of nano-materials, and particularly relates to a preparation method and application of a hydrophilic rare earth nano-material, and the method is as follows: a rare earth nitrate and chloride as rare earth sources, sodium fluoride and ammonia fluoride as fluoride sources, sodium chloride and sodium nitrate as sodium sources, ethylene glycol and ethanol as solvents and a surface functionalization ligand are mixed and stirred evenly according to certain mole ratio, the evenly-stirred solution is transferred into a hydrothermal kettle for water / solvent heat treatment. After natural cooling, deionized water and ethanol are used for in turn centrifuging, and the obtained precipitate is put into an oven for baking for 6-12 h at 60-120 DEG C under the condition of air to obtain the hydrophilic rare earth nano-material, by use of the one-step water / solvent heat method, the preparation technology is simple, the obtained hydrophilic rare earth nano-material has good stability, high luminous efficiency, adjustable size, controllable morphology, short cycle, low cost, high yield, no toxicity, and no pollution, and can be widely used in security, biological molecular fluorescent tag, biological imaging and other fields.