59results about How to "Good fluorescence emission spectral characteristics" patented technology

The invention discloses application of a near infrared-emission fluorescent probe in quick pesticide residue detection and belongs to the technical field of quick pesticide detection. The probe is based on rhoda-fluor fluorescence matrix and has specific activity on acetylcholine esterase AChE; by means of an enzyme inhibition detection principle, the probe can be applied to quick detection of organophosphorus pesticide and carbamate pesticide residues in food. The acetylcholine esterase AChE is extracted from duck blood; in an appropriate probe substrate range, enzyme activity and an inhibition rate can be represented by quantitatively detecting fluorescence intensity change of the probe. Four pesticide detection standard curves have small error, and R<2> is larger than 0.98; vegetable pesticide adding standard recovery most reaches 80 to 110%, so that the near infrared-emission fluorescent probe disclosed by the invention can be applied to quantitative, ppb-grade and quick detectionof organophosphorus and carbamate pesticide residues in the food.

The invention discloses fluorescent test paper capable of rapidly detecting formaldehyde. The fluorescent test paper is formed by fluorescent-whitening-agent-free test paper loaded with fluorescent probe naphthalimides derivative. The fluorescent test paper is deep green, the size of the test paper is (100-75)mm*(15-8)mm*(1-0.5)mm, the content of the naphthalimides derivative loaded on each fluorescent test paper is not less than 0.01mg, the test paper for a substrate is deep-green precision pH test paper, and the naphthalimides derivative loaded on the test paper for the substrate is N-amino-4-(1-piperazinyl)-1,8-naphthalimide, N-amino-4-(1-piperazinyl)-1,8-naphthalimid or N-amino-4-(1-pyrrolidinyl)-1,8-naphthalimide. The fluorescent test paper is easy to prepare, convenient to use and capable of rapidly and accurately detecting and determining the formaldehyde in the environment.

The invention provides a fluorescent probe for detecting hydrogen sulfide in cells, a method for preparing the fluorescent probe and application thereof. A chemical structural formula of the fluorescent probe is shown. Reaction can be carried out on 2,4-dinitrofluorobenzene and reaction products of 4-ethynylbenzonitrile and 4-bromine-2-hydroxybenzaldehyde to obtain the fluorescent probe. The hydrogen sulfide in solution or the cells or organisms can be detected by the fluorescent probe by the aid of fluorescence. The fluorescent probe, the method and the application have the advantages that the fluorescent probe can be obtained by means of chemical synthesis, synthesis processes are simple and feasible, raw materials are inexpensive and are easily available, and accordingly the fluorescentprobe is low in preparation cost; the fluorescent probe is high in specificity, and interference due to other components can be prevented in detection procedures; the fluorescent probe is short in response time, high in sensitivity and excellent in fluorescence emission spectral characteristic, and the hydrogen sulfide in the cells can be quickly and accurately detected by the fluorescent probe;the fluorescent probe has a broad application prospect in research on the influence of the hydrogen sulfide in the biological cells on physiological and pathological procedures.

The invention provides a detection reagent and a quantitative detection method of human serum albumin and belongs to the technical field of fine chemical engineering. Based on a combining attribute of albumin and small molecules, the specific principle of the method is that HCAB can be specifically combined with the albumin, a charge transferring phenomenon in HCAB twisting molecules is inhibited and non-radiation transition is reduced, so that fluorescent light is recovered and quantitative detection of the albumin is realized. After the human serum albumin is excited under a physiological pH value condition (an excitation wavelength lambdaex is equal to 424nm), a stable fluorescent signal (an emission wavelength lambdaem is equal to 526nm) is generated. The fluorescent value intensity is in direct proportion to the concentration of the albumin; and according to a detected fluorescent value, the content of the albumin in a biological sample can be calculated. The method can be used for determining absolute content of the albumin in a plurality of types of biological samples including blood serum, urine and the like; and meanwhile, the method also has the advantages of high sensitivity, high accuracy, high environment interference resisting capability, easiness of carrying out high-flux detection and the like.

A high-specificity fluorescent probe of human carboxylesterase CES2 and an application thereof. A substrate of the high-specificity fluorescent probe is an ester derivative of a 3-hydroxyl flavonoid compound, which can be used for detecting the existence of the CES2 in different bio-samples and quantitatively measuring the activity of the CES2. A particular measurement process of the enzyme activity includes following steps: selecting a hydrolysis reaction of the derivative of the 3-hydroxyl flavonoid compound as a probe reaction; selecting generation amount of a hydrolytic metabolite, 3-hydroxyl flavonoid, in unit time through quantitative detection with selection of a proper substrate concentration in a linear reaction section so that the actual activity of the CES2 enzyme in various bio-samples, cells, in-vivo organs and overall organs can be measured. The high-specificity fluorescent probe not only can be used for quantitative evaluation of the enzyme activity of the CES2 in the bio-samples from different sources, but also can be used for in-vitro quickly screening an inhibitor of the CES2 by means of the probe reaction.

The invention relates to a cytochrome oxidase CYP1A1 specific fluorescent probe, a preparation method and applications thereof, wherein the specific probe substrate has a 4-hydroxynaphthalimide structure, and can be used for determining the CYP1A1 enzyme activity in a biological system. The CYP1A1 enzyme activity determination process comprises: selecting a 4-hydroxynaphthalimide dechloroethylation reaction as a probe reaction, and determining the activity of the CYP1A1 enzyme in various biological samples by quantitatively detecting the generation amount of the dechloroethylation metabolites per unit time. According to the present invention, the cytochrome oxidase CYP1A1 specific fluorescent probe can be used for the quantitative evaluation of the CYP1A1 enzyme activity in biological samples having different species and different individual sources, and the quantitative determination of the CYP1A1 enzyme activity in animal culture cell culture liquids and cell preparation products from different origins so as to evaluate the drug treatment capacity of the important drug metabolic enzyme CYP1A1; and the probe reaction can further be used for rapidly screening inhibitors and inducers of CYP1A1 in vitro and evaluating the inhibition ability.

The invention provides a two-photon fluorescent probe for detecting hypochlorous acid in a cellular endoplasmic reticulum. The two-photon fluorescent probe can be obtained through a three-step reaction by using 4-methylthio-1,8-naphthalic anhydride, trifluoroacetic acid and p-toluenesulfonyl chloride as raw materials. The two-photon fluorescent probe can be applied to detection of the hypochlorousacid in a solution or the cellular endoplasmic reticulum. The fluorescent probe can be obtained through chemical synthesis, a synthesis technology is simple and easy to implement, the raw materials are cheap and easy to obtain, the preparation cost is low, and the fluorescent probe is easy to popularize, has high specificity, is not interfered by other components, can be applied to real-time determination of the hypochlorous acid in the endoplasmic reticulum of a living cell and has a broad application prospect.

The invention discloses a fluorescence probe for detecting hypochlorous acid in a biological system. The fluorescence probe is a benzopyran derivative containing different substituent groups, and the chemical construction general formula of the fluorescence probe is shown as the formula (I). The fluorescence probe is easy to manufacture and low in cost, has the high specificity, can make a chemical reaction with the hypochlorous acid to generate a corresponding oxidative product, cannot be disturbed by other components when the corresponding hypochlorous acid content detecting process is executed, can be used for quantitative and qualitative determination on the content of the hypochlorous acid in living cells and has the wide application prospect.

The invention discloses a high-specificity fluorescent probe for human carboxylesterase hCE2 and an application thereof. The substrate of the specific probe is an ester derivative of a 4-trifluoromethyl-7-umbelliferone compound and can be used for detection for the existence of hCE2 in different biological samples and quantitative determination for the vitality of hCE2. A specific flow for determining the enzymatic activity is as follows: selecting a hydrolysis reaction of the 4-trifluoromethyl-7-umbelliferone ester derivative as a probe reaction, selecting a proper substrate concentration, and determining the actual activity of the hCE2 enzyme in various biological samples, cells, carriers and overall organs by quantitatively detecting the generation amount of a hydrolysis metabolite 4-trifluoromethyl-7-umbelliferone in a unit time within a linear reaction interval. The high-specificity fluorescent probe disclosed by the invention can be used for quantitative evaluation for the activity of the hCE2 enzyme in biological samples from different sources; in addition, the probe reaction can also be used for rapidly screening an hCE2 inhibitor in vitro.

The invention provides a specific fluorescent probe for COMT and application thereof. A specific probe substrate provided by the invention is 3-benzothiazole-7,8-dihydroxycoumarin (3-BTD); the substrate can be specifically catalyzed by COMT to produce an 8-methoxy product and presents a fluorescence signal at a position of 520 nm; and the activity of COMT can be quantitatively determined by detecting changes of fluorescence intensity. The probe is applicable to quantitative assessment of the activity of COMT in biological samples from different sources, in-vitro rapid screening of inhibitors for COMT and evaluation of the inhibitory capability of the inhibitors. A method provided by the invention can be used for quantitative assessment of the actual activity of COMT in a variety of in-vitro biological samples and realizes rapid screening of inhibitors and quantitative assessment of the inhibitory capability of the inhibitors; the method is also applicable to evaluation of the catalytic activity of COMT of different species and COMT mutants with different amino acid sequences, so the method can assess the capability of COMT in metabolization of catechol drugs; and the method has the advantages of high sensitivity, high accuracy, good environment interference resisting capability, convenience in high-flux detection and inhibitor screening, etc.

The invention provides a fluorescence probe for detecting hydroxylamine. The fluorescence probe is a rhodamine derivative containing biotin groups; benzoic acid groups are hydroxylamine response sites; a fluorescence peak value of the probe before the probe is reacted with hydroxylamine is about 637nm; the peak value of the probe after the probe is reacted with hydroxylamine is about 590nm; the hydroxylamine can be qualitatively detected through fluorescence intensity ratio change under two wavelengths; a linear relation is formed between the fluorescence intensity ratio under two wavelengthsand the concentration of hydroxylamine, so that the concentration of hydroxylamine can be quantitatively detected. The fluorescence probe is high in specificity, high in sensitivity and excellent in fluorescence emission spectrum characteristics (550-750nm).

The invention discloses a novel polysiloxane-benzoxazine-based luminescent film and its application in a UV-LED light. A film matrix is a copolymer of siloxane and benzoxazine. The matrix polymer hasa general chemical formula shown in the description. Rhodamine B as a physical cross-linking site is introduced into the matrix and the film is prepared through a one-pot method. The luminescent filmis easy to prepare and realizes a low cost. The film can emit fluorescence in two wave bands under excitation of different wavelengths of fluorescence and regulation and control of the emission wave bands are realized through changing different excitation wavelengths. The film has a wide application prospect.

The invention relates to a method for detecting the activity of catechol-oxygen-methyltransferase (COMT) in blood and belongs to the technical field of biological medicine. According to the invention,3-benzothiazole-7,8-dihydroxycoumarin (3-BTD) with high chemical stability is selected as the fluorescence substrate of COMT enzyme by virtue of the advantages of a high performance liquid chromatography and fluorescence detection combined instrument on biological matrix interference resistance and detection sensitivity; meanwhile, a high-efficiency and high-sensitivity measuring method capable of quantitatively analyzing the activity of a trace amount of COMT in the blood is developed by combining a high performance liquid chromatography-fluorescence detection technology. A fluorescence probe substrate adopted by the method can be obtained through chemical synthesis, the synthesis process is simple and practical, and the performance is stable. The method has the advantages of high sensitivity, high accuracy degree, high biological matrix interference resistance, high repeatability and the like, can be applied to detection on the activity of the COMT enzyme in the blood, and also canbe applied to quantitative measurement on the activity of the COMT enzyme in various mammal-derived cells or tissue preparation objects as well as screening and evaluation of a COMT inducer/activator.

The invention provides a fluorescent probe for detection of hydrogen sulfide. The fluorescent probe can be used to detect hydrosulfide ions or sulfions in solutions or cells. The fluorescent probe ofthe invention can be obtained by chemical synthesis, and a synthesis technology of the fluorescent probe has the advantages of simplicity, easiness in implementation, cheap and easily available raw materials, low preparation cost, and easiness in promotion. The fluorescent probe of the invention has the advantages of good targeting property to the lysosome, high sensitivity to the lysosome, good fluorescence emission spectrum characteristics (415-600 nm), realization of the quantitative detection of H2S in the cell lysosome by drawing a standard curve, and achieving of the purpose of rapidly and accurately detecting H2S in the cell lysosome. The fluorescent probe of the invention has a high specificity, is not prone to be interfered by other components in the corresponding H2S detection process, can be used for real-time detection of H2S in the living cell lysosome, and has a broad application prospect.

The invention discloses a human carboxylesterases 2 detection kit and application method and application thereof. The kit comprises liquid A, liquid B, liquid C and a quality control standard substance, and the liquid A refers to a 100mM phosphate buffer solution with pH (potential of hydrogen) ranging from 5.5 to 10; the liquid B refers to a 0.1-10mM NCEN solution with an solvent of any optional one of methyl alcohol, acetonitrile or dimethyl sulfoxide; the liquid C refers to the acetonitrile or the methyl alcohol; the quality control standard substance refers to a 5mg/ml hCE2 solution. The kit is used for rapid quantitative detection of activity of the human carboxylesterases 2 and rapid screening and evaluation of enzyme inhibitors. The human carboxylesterases 2 detection kit and application method and application thereof have the advantages of simpleness in operation, low cost, flexibility and rapidness for per unit detection, and high-throughput detection can be achieved.