166results about How to "Fluorescent signal enhancement" patented technology

A method for assaying a sample for a nucleic acid damaging activity using at least one singular double-stranded nucleic acid with at least one electrochemiluminescent label, and a method for measuring an inhibitor of a nucleic acid damaging activity with at least one singular double-stranded nucleic acid using at least one electrochemiluminescent label, are disclosed.

Improved methods, systems and apparatus relating to wide field fluorescence and reflectance imaging are provided, including improved methods, systems and apparatus relating to removal of background signals such as autofluorescence and / or fluorophore emission cross-talk; distance compensation of fluorescent signals; and co-registration of multiple signals emitted from three dimensional tissues.

The invention relates to a method for detecting ochratoxin A. The method utilizes a nucleic acid aptamer sequence fixed on a photonic crystal microsphere and a fluorescence labeled complementary sequence thereof for hybridization; after addition of a sample to be detected, a chip scanner is employed to detect fluorescence signals before and after addition of the sample; and change value of the measured fluorescence signal is used for detection of ochratoxin A in the sample. The method has detection limit of 0.001 ng / mL on ochratoxin A, linear detection range from 0.001 to 1 ng / mL; and only 2 muL of specimen is required.

The present invention provides for novel reagents whose fluorescence increases in the presence of particular proteases. The reagents comprise a characteristically folded peptide backbone conjugated to two fluorophores such that the fluorophores are located opposite sides of a cleavage site. When the folded peptide is cleaved, as by digestion with a protease, the fluorophores provide a high intensity fluorescent signal at a visible wavelength. Because of their high specificity and their high fluorescence signal in the visible wavelengths, these protease indicators are particularly well suited for detection of protease activity in biological samples, in particular in frozen tissue sections. Thus this invention also provides for methods of detecting protease activity in situ in frozen sections.

Improved methods, systems and apparatus relating to wide field fluorescence and reflectance imaging are provided, including improved methods, systems and apparatus relating to removal of background signals such as autofluorescence and / or fluorophore emission cross-talk; distance compensation of fluorescent signals; and co-registration of multiple signals emitted from three dimensional tissues.

New photosensitive optically variable inks are capable of printing images having improved resistance to water. The inks produce images which can be viewed with both visible and ultraviolet light to have physically coincident positive and negative images. They contain at least two types of colorants and other suitable ingredients to enable preparation for printing. The first colorant comprises a fluorescent dye emitting light within a characteristic emission band when excited by fluorescent-exciting radiation. The second colorant, which comprises a colloidal pigment alone or with a dye, has a light absorption band at longer wavelengths than the characteristic emission band of the first colorant or overlapping the emission wavelength of the first colorant, effectively to result in a dark color. The composition also contains an aqueous liquid vehicle comprising water and a water-soluble vehicle in sufficient amounts to achieve an ink viscosity and surface tension effective for application of the ink to a substrate in a predetermined pattern by ink jet printing.

The invention discloses a fluorescent reagent for detecting trace gamma-globulin, as well as a preparation method and application thereof, and belongs to the field of fluorescent bio-sensors. The fluorescent reagent is prepared from TABD-Py-PF6 and a good solvent. The preparation method comprises the following steps: dissolving (1Z,3Z)-1,4-di(4-methoxycarbonyl) phenyl-1,4-dibromo-1,3-butadiene in the good solvent, adding 4-pyridine phenylboronic acid, a catalyst and a basic salt, and reacting to obtain TABD-Py; dissolving the TABD-Py in a solvent, adding iodomethane to synthesize iodate, adding potassium hexafluorophosphate, and reacting to obtain TABD-Py-PF6; dissolving the TABD-Py-PF6 in the good solvent to obtain the fluorescent reagent. The fluorescent reagent does not need participation of metal ions, has a specific lighting-type fluorescent response on gamma-globulin, has high and quick sensitivity on gamma-globulin detection, and has high selectivity. The fluorescent reagent has an excellent visible detection signal, can be completely separated from high-precision instruments according to actual requirement, and can meet current requirement for detecting the gamma-globulin in serum to a great extent.

The invention relates to the field of fluorescent quantitative detection and provides a high-sensitivity nano composite probe for the fluorescent quantitative detection of a blood serum tumor marker.The nano composite probe comprises gold nanoparticles loaded with a blood serum tumor marker secondary antibody to be detected and a DNA (Deoxyribonucleic Acid) enzyme chain. The nano composite probeprovided by the invention takes the gold nanoparticles as carriers and a compound formed by loading deoxyribozyme with a high catalytic property keeps the high catalytic property and recognition capability of the deoxyribozyme, and also introduces a signal transduction function of a nano-material, so that recognition and signal transduction functions are integrated. The sensitivity and specificityof the fluorescent quantitative detection are remarkably improved by combining an efficient specific recognition function of the tumor marker, high recognition and catalytic properties of the deoxyribozyme, and signal transduction and fluorescent amplification functions of the gold nanoparticles; the detections sensitivity can reach 0.01ng / mL.

The invention provides a novel coronavirus nucleic acid detection kit. The novel coronavirus nucleic acid detection kit comprises two crDNAs or two crRNAs. The crDNAs comprise a crDNA of a targeting Egene and a crDNA of a targeting N gene, wherein the sequence of the crDNA of the targeting E gene is as shown in any one of SEQ ID NO.3-5, the sequence of the crDNA of the targeted N gene is shown asany one of SEQ ID NO.6-8. The crRNAs comprise a crRNA of the targeting E gene and a crRNA of the targeting N gene, wherein the sequence of the crRNA of the targeting E gene is as shown in any one ofSEQ ID NO.9-11, and the sequence of the crRNA of the targeting N gene is as shown in any one of SEQ ID NO.12-14. The crRNAs related to the novel coronavirus E gene and the novel coronavirus N gene aredesigned, and screening detection is carried out in combination with a CRISPR-cpf1 system. The method has the advantages of being simple, high in speed, high in sensitivity, high in specificity and extremely high in practicability.

The invention discloses a fluorescence enhanced chip based on an all-medium artificial microstructure super-surface. An upper layer of the chip is composed of periodically-arranged nano-medium columnclusters, and a lower layer is a medium substrate; the refractive index of the upper layer is greater than that of the lower layer; the collective magnetic dipole resonance wavelength and the collective electric dipole resonance wavelength of the chip satisfy that one is equal to the excitation wavelength of a fluorescent marker, and the other is equal to the radiation wavelength of the fluorescent marker. In the periodically-arranged nano-medium column clusters, each of periodic units is a square or a regular hexagon of the same size; four nano-medium columns of the same size are contained ineach of the periodic units. The fluorescence enhanced chip disclosed by the invention has the benefits that a fluorescence signal is simultaneously enhanced from three aspects of enhancing an excitation light local field, improving the radiation quantum efficiency and improving the fluorescence collection efficiency, so that the detection sensitivity of the fluorescent marker is greatly improved.The whole chip is arranged on a low-refractive index substrate and has the advantages that the material loss is low, the preparation is simple, and the structure size can be changed to work in different wavebands.