33 results about "Fluorescence anisotropy" patented technology

The invention relates to a high-accuracy fluorescence anisotropy microscopic imaging device and method. The imaging method comprises the following steps of: on a reflective fluorescence microscope, leading lights emitted by a light source to pass through a polarizer, an excitation filter plate and a spectroscope, and then focusing the lights on a sample; leading fluorescence reflected by the sample to pass through an objective lens, the spectroscope and an emission filter plate, and then imaging on an image plane of a CCD (Charge-Coupled Device) camera through an adjustable angle analyzer; controlling the adjustable angle analyzer to rotate around an optical axis of an imaging optical path step by step by using a computer, wherein when the adjustable angle analyzer rotates by an angle every time, the CCD camera shoots a frame of polarized fluorescence image, M images are totally shot; and finally calculating fluorescence anisotropic images from the M images by using Fourier transform.The imaging method is characterized in that the measuring resolution ratio of the fluorescence anisotropy is greatly improved by establishing a single-channel fluorescence analyzing optical path; andthe microscopic imaging system has higher stability and better anti-jamming capability.

A non-invasive measurement of biological tissue reveals information about the function of that tissue. Polarized light is directed onto the tissue, stimulating the emission of fluorescence, due to one or more endogenous fluorophors in the tissue. Fluorescence anisotropy is then calculated. Such measurements of fluorescence anisotropy are then used to assess the functional status of the tissue, and to identify the existence and severity of disease states. Such assessment can be made by comparing a fluorescence anisotropy profile with a known profile of a control.

A Polarization Fluorescence Photoactivation Localization Microscopy (P-FPALM) system and method are provided to simultaneously image the localizations and fluorescence anisotropics of large numbers of single molecules within a sample. The system modifies known FPALM systems by adding a polarizing beam splitter. The beam splitter polarizes emissions perpendicular and parallel to an axis in the sample to allow spatially separate imaging of fluorescence emitted from a sample. The system includes lenses and mirrors so that the separate, polarized beams are detected simultaneously. The present invention includes methods of using the system to image localizations and fluorescence anisotropics of single molecules, and methods of using data obtained with the system to predict 3-D orientation of the molecules. The system and method achieve substantially improved lateral resolution within even dense samples over known microscopic imaging techniques, and does not compromise speed or sensitivity.

The present invention relates to methods for detecting the presence of one or more analytes of interest in a sample by measuring changes in fluorescence anisotropy as a result of binding of the analytes to specific aptamers. The aptamers are immobilized on a solid support and may be in the form of an array.

The invention discloses a method for measuring a polarization degree and a polarization angle of a fluorescence spectrum. The method is used for solving the problems of different measurement polarization angles and errors changing over the fluorescence polarization angles during conventional fluorescence anisotropy measurement. The method is characterized by comprising the steps of regulating a polarization direction of a polarization detection polarizer to be parallel with a polarization direction of an emergent ray (completely polarized light) of a polarizer by adopting a common L measurement manner in fluorescence measurement through rotating the polarization detection polarizer, then clockwise rotating the polarization detection polarizer for 0 DEG, 45 DEG, 90 DEG and 135 DEG, respectively measuring by using a spectrograph and recording the fluorescence spectrum intensity, and calculating the polarization degree and the polarization angle by using the obtained fluorescence spectrum intensity. Compared with the prior art, the method has the beneficial effects that the polarization degree and the polarization angle of the fluorescence spectrum can be simultaneously obtained, and the polarization degree is more accurate.

The invention provides a kit for detecting an ATP with a nucleic acid aptamer and a detection method thereof. The kit comprises a nucleic acid aptamer having a sequence as shown in SEQ ID NO. 1 or SEQ ID NO. 2, and an ATP labeled by Tetra-Methyl Rhodamine (TMR). The kit achieves detection of the ATP based on fluorescence polarization (fluorescence anisotropy) of the nucleic acid aptamer, and has the advantages of simple operation, fast detection, high sensitivity, high accuracy and good reproducibility, and is insusceptible to fluorescence intensity fluctuation and fluorescence photobleaching. Compared with such methods as chromatography, no expensive instrument is needed and the operation steps are simple; and moreover, determination can be achieved just by simple sample mixing.

The invention discloses a method for analyzing aflatoxin B1 by fluorescence anisotropy of a sensitive aptamer. The method protected by the invention comprises the steps of: subjecting the aptamer marked by means of a fluorochrome, single-chain DNA molecules marked by means of streptavidin and a to-be-tested sample to co-reaction, and realizing detection of aflatoxin B1 in the to-be-tested sample through determining a fluorescence anisotropic value of a reaction system, wherein the aptamer can be specifically bound to the aflatoxin B1, and the single-chain DNA molecules can form a double-chainstructure with the aptamer through reverse complementation; and placing the fluorochrome and the streptavidin on the same end of the double-chain structure after the single-chain DNA molecules form the double-chain structure with the aptamer through reverse complementation, wherein the fluorochrome and the streptavidin are closed to each other spatially. The method has the advantages of being sensitive, simple and rapid, having good repeatability, being easy in high-throughput analysis, having low sample consumption and the like, the materials used are easy to prepare, the synthesis cost is low, the stability is good, the storage and transportation are convenient, the life of the shelf is long, and the method has high sensitivity and good selectivity.

The invention discloses a sulfion sensor based on polyethylene glycol and a preparation method and application thereof. A fluorescence sensor is prepared by raw materials such as monoamino group polyethylene glycol, 4-bromine-1, 8-anhydride naphthalene and sodium azide, and the fluorescence sensor can identify a sulfion with high sensitivity and high selectivity in the water. According to the sensor, the sulfion is identified selectively through the theory of intramolecular charge transfer (ICT). Due to the fact that sulfion concentration in a system increases gradually, the reducibility of the sulfion can give rise to the generation of the ICT process in the sensor, the fluorescence of the sensor is enhanced gradually, and the absorption strength changes correspondingly. Compared with an existing fluorescence detection technology, the fluorescence sensor is great in water solubility, the detection to the sulfion is high in sensitivity and good in selectivity, the synthetic route is simple, the detection equipment and method are simple and convenient, the sensor is applicable to magnify synthesis and practical production application, and the sensor has a vast application prospect in technical fields such as analytical chemistry, life sciences and environmental sciences.

The invention relates to a system and method for carrying out polarization super-resolution imaging on fluorescence anisotropy. According to the system, an optical phase-locked detection technology and a linear dichroic system are used to obtain a polarization modulation image sequence. The method comprises the following steps of: S1, carrying out frequency domain phase-locked processing on an acquired fluorescence image sequence modulated by rotating polarized light, extracting signals with the same modulation frequency, and obtaining a sequence image IOLID which only retains background and modulation frequency information; and S2, performing demodulation, namely three-dimensional deconvolution, on the sequence image IOLID to obtain a super-resolution ac image G'ac, a reconstructed dc image G'dc and a super-resolution reconstructed image G 'at the same time, and performing phase extraction to obtain a dipole orientation distribution image. The OLID-SDOM disclosed by the invention reveals fluorescence anisotropy which is never observed before in part of samples, which shows that the OLID-SDOM has potential to observe dynamic molecular structures; and compared with a traditional microscope, the OLID-SDOM has the advantages that the spatial resolution is doubled, and biological samples are not limited during imaging.

The invention discloses a method for detecting ochratoxin A through a fluorescence anisotropy technology. According to the method, an aptamer capable of being specifically combined with the ochratoxinA is selected and marked with a fluorochrome; a single-stranded DNA molecule which is complementary to the aptamer is designed for the aptamer, and marked with streptavidin; after the aptamer is combined with the single-stranded DNA molecule, the fluorochrome and the streptavidin are adjacent to each other in space; the prepared aptamer and the prepared single-stranded DNA molecule react with a to-be-tested sample, and by measuring the fluorescence anisotropy value of the reaction system, the ochratoxin A in the to-be-tested sample is detected. The built method has the advantages that the method is sensitive, simple, quick and good in reproducibility, high-throughput analysis is easy to achieve, and the use quantity of the sample is small; the adopted materials are easy to prepare, the synthesis cost is low, the stability is high, storage and transportation are convenient, the shelf life is long, and the sensitivity and selectivity are high.

The invention discloses a blue light polarizing thin film and a preparation method thereof as well as a blue light backlight source and a liquid crystal display device. The blue light polarizing thin film disclosed by the invention is a multi-layer thin film formed by virtue of layer-by-layer deposition of magnesium-aluminum hydrotalcite and tri(8-hydroxyquinoline-5-sulfonic acid) aluminum. The maximum emission value of fluorescence spectrum of the blue light polarizing thin film disclosed by the invention is 470-490nm; within a blue light area and fractional anisotropy of fluorescence is 0.1-0.2, the thin film has a polarizing characteristic and is applicable to the backlight source of a liquid crystal display.

Nano-structured anodic aluminum oxide ceramic films and membranes doped with chelated metals for fluorescence enhancement. Controlled doping during production steps results in the inclusion of traces of ions in the finished materials while maintaining high control over the film structure. This approach yields products suitable for optical applications, including fluorescence enhancement. The nano-structured anodic aluminum oxide ceramic films and membranes are particularly useful for in vitro diagnostics, drug discovery, DNA sequencing, proteomics, immunofluorescence, immunohistochemistry, biosensing, and bio-assay fluorescence technologies such as time resolved Forster resonance energy transfer (TR-FRET), Fluorescence in situ hybridization (FISH), Fluorescence-lifetime imaging microscopy (FLIM), Fluorescence polarization immunoassay (FPIA), Fluorescence anisotropy or fluorescence polarization, Fluorescence recovery after photobleaching (FRAP), Fluorescence Loss in Photobleaching (FLIP), Fluorescence correlation spectroscopy (FCS), and Falck-Hillarp fluorescence (F-H).

The invention relates to an application of amentoflavone in preparation of a staphylococcus aureus transcriptional adjustment factor (MgrA) inhibitor, the staphylococcus aureus transcriptional adjustment factor (MgrA) is taken as a drug target, and the drug amentoflavone capable of remarkably inhibiting the activity of the MgrA is screened from natural compounds by using a fluorescence anisotropy analysis method. The toxicity of the methicillin-resistant staphylococcus aureus can be obviously reduced on the premise of not influencing the normal growth of bacteria, and the generation of bacterial drug resistance is not easily caused. In in-vivo experiments, amentoflavone has a remarkable treatment effect on mouse pneumonia caused by methicillin-resistant staphylococcus aureus infection, and can greatly improve the viability of infected mice and relieve the inflammatory response of lung tissues. In conclusion, the amentoflavone serves as an effective staphylococcus aureus transcriptional adjustment factor MgrA inhibitor, and a new research and development strategy and a lead compound are provided for effectively preventing and treating methicillin-resistant staphylococcus aureus infection clinically.

The invention relates to a measuring method for fluorescence characteristics of a fluorescence product and particularly relates to a method for quantitative measurement method for fluorescence lifetime and fluorescence dynamic anisotropic parameters. The method comprises the steps of: exciting a product by a pulse or sine polarization exciting light to produce fluorescence; detecting intensity of polarized fluorescence which is parallel to the pulse or sine polarization exciting light and intensity of polarized fluorescence which is perpendicular to the pulse or sine polarization exciting light respectively with a photoelectric detector; and calculating the average life, the fluorescence anisotropy at the initial time, the fluorescence anisotropy at the infinite time and fluorescence molecule rotational correlation time of the sample. With the adoption of the method provided by the invention, the fluorescence lifetime of all samples can be effectively and quantitatively measured; moreover, the invention provides a quantitative measurement method for fluorescence parameters of the fluorescence product, so the method has great application value for quantitative study of the interaction between large biological molecules, such as proteins, in the living cell.