96results about How to "Enhanced fluorescence emission" patented technology

The invention provides fluorescent probe compounds, a preparation method and use thereof, belonging to the detection of palladium ions in the field of fine chemical industry. The fluorescent probe compounds designed on the basis of the 'opening-closing' property of the spiral ring in the molecule of a rhodamine luminescent dye well solve the difficult problem that the palladium ions quench fluorescence. The excitation wavelength and the emission wavelength of the probe compounds are both in a visible light region. The compounds have excellent selectivity to the palladium ions in the practical detection range of nearly neutral pH and have excellent sensitivity. The fluorescence is obviously enhanced in the process of detecting the palladium ion concentration of 0-10ppb, an excellent linear relationship between the palladium ion concentration and the fluorescence enhancement is formed, and the palladium ions of 5nm can be detected at lowest. The probe compounds have extremely quick response for distinguishing the palladium ions and are the reported palladium ion probes with the shortest response time so far. The probe compounds can be used for realizing the detection of the palladium ions in the two manners of fluorescent light and color comparison, and has potential application value in the detection of palladium pollution and residual level in medicines, water samples, soils and catalytic reactors.

The present invention relates to an assay including a surface having silver colloids or islands attached thereto. Attached to the surface and / or silver colloids / islands are polynucleotides which are complimentary to a target polynucleotide sequence. The assay is performed by adding the target polynucleotide sequence to the assay surface and allowed to hybridize with the capture polynucleotides. Fluorophore-labeled capture polynucleotides are added and hybridize to the target polynucleotide. Bound target polynucleotides are detected by metal enhanced fluorescence.

Disclosed are nitro-substituted squaraine reporter dyes and methods using such dyes for detecting nitroreductase enzyme activity and nitroreductase gene expression in cellular assays. The dyes are of the structure:in which Z1 and Z2 independently represent a phenyl or a naphthyl ring system; X and Y are selected from oxygen, sulphur, —CH═CH— and the group:R1 and R2 are selected from C1-C4 alkyl, —(CH2)n—P, —{(CH2)2—O}p—R6 and group W; where P is selected from COOR7, SO3− and OH, W is mono- or di-substituted nitrobenzyl, R6 is methyl or ethyl, R7 is selected from H, C1-C4 alkyl and CH2OC(O)R8, where R8 is methyl, or t-butyl, n is an integer from 1 to 10, and p is an integer from 1 to 3; R3 and R4 are selected from hydrogen, NO2, halogen, SO3−, C1-C4 alkoxy and —(CH2)m—COOR7; where R7 is hereinbefore defined and m is 0 or an integer from 1 to 5; R5 is C1-C6 alkyl optionally substituted with COOR7, SO3−, or OH; where R7 is hereinbefore defined; and at least one of groups R1, R2, R3 and R4 comprises at least one NO2 group. Also provided are methods for screening for a test agent whose effect upon nitroreductase enzyme activity and nitroreductase gene expression is to be determined.