47 results about "Dna integrity" patented technology

The present invention relates, e.g., to a method for determining the size distribution of DNA molecules in a sample comprising cell-free nucleic acid, comprising labeling the DNA with a fluorescent dye in a stoichiometric manner, subjecting the DNA to molecular spectroscopy (e.g., cylindrical illumination confocal spectroscopy), analyzing suitable fluorescent burst parameters of the labeled DNA, and conducting single molecule DNA integrity analysis of the labeled DNA molecules in the sample. In one embodiment of the invention, the method is used as a diagnostic method for detecting cancer.

The invention relates to a composite for preservation of human saliva and a preparation method of the composite. The composite comprises the following components: Tris-HCl with pH being 6-8.5 (5-20mmol/L), EDTA (Ethylene Diamine Tetraacetic Acid) (0.5-2mmol/L), NaOAc (2.5-3.5mol/L), cane sugar (0.1-0.4mol/L), N-acetyl-5-methoxytryptamine (1-3mmol/L), propylparaben (1-4mg/mL), diazonium imidazolidinyl urea (1-3mg/mL), protease K(10mu g/mL) and a system with pH being 7.5-8.5. When used for preservation of human saliva, the composite is capable of inhibiting nuclease activity and preventing nuclease from being contaminated by external microbes or being oxidized by itself, thereby guaranteeing the integrality and the purity of genomic DNA (deoxyribonucleic acid). The composite is long in preservation period, wide in preservation temperature range and applicable to gene detection and related scientific researches.

The invention relates to a construction method of a systemic lupus erythematosus map model. The construction method comprises: setting a systemic lupus erythematosus group and a control group, wherein each group comprises a plurality of peripheral blood samples isolated from human body and derived from different people; respectively extracting DNA from each peripheral blood sample to obtain DNA liquids to be detected; determining the DNA contents and the DNA integrity in the DNA liquids to be detected, detecting whether the sample is qualified, and performing the next step if the sample is qualified; constructing a gene library by using a multiplex PCR technology, detecting whether the gene library is qualified, and performing the next step if the gene library is qualified; carrying out sequencing on the gene library by using a high-throughput sequencing technology; and analyzing the sequencing results, and constructing the systemic lupus erythematosus map model. According to the construction method of the systemic lupus erythematosus map model of the present invention, the design is reasonable and feasible, and the SLE related information adopted as the middle results can be effectively obtained.

The invention discloses a preparation method of a burkholderia gladioli molecular standard sample. The preparation method comprises the step of carrying out freeze drying on extracted genome nucleic acid of burkholderia gladioli, wherein the freeze drying conditions are as follows: a freeze dryer is started, and a cooling trap is started when temperature of a drying chamber is lowered to -35 DEG C; when the temperature of the cooling trap is lowered to -40 DEG C, a nucleic acid sample prefrozen for 2 hours at the temperature of -80 DEG C is put into the drying chamber and then vacuumized; when vacuum degree is reduced to 0.5Torr, freezing is finished; and the sample is dried at the temperature of 15 DEG C, the sample is taken out when the vacuum degree is reduced to 0.1Torr, a penicillin bottle is tightened to obtain a burkholderia gladioli genome nucleic acid standard sample, and the sample is kept in a dark place and stored at the temperature of 20 DEG C. The molecular standard sample disclosed by the invention has good physical and chemical properties and can be detected by adopting a specific primer through PCR process, and sensitivity reaches 10<-4>. Detection test shows that the standard sample has good DNA integrity, uniformity and stability, can be applied to import and export detection as a positive reference material, and accuracy of a detection result is improved.

The present invention relates to methods for predicting the survival time of patients suffering from cancer. Said methods are based on the quantification and analysis of the cell free nucleic acids that are present in a sample from the patient and typically include the determination of the level of the mutant nucleic acid which contains a mutation of interest, the calculation of the mutation load for said mutation of interest, the calculation of the DNA integrity index or a combination thereof.

The invention discloses a quick extraction method of plant genomic DNA (Deoxyribonucleic Acid). The quick extraction method is characterized by comprising the following steps of (1), taking a plant tissue sample, adding liquid nitrogen, grinding the plant tissue sample into powder and collecting into a centrifugal tube, and the like. SDS (Sodium Dodecyl Sulfonate) in a Buffer A in the quick extraction method can be used for cracking a cell membrane to denature protein; a Buffer B can act with the SDS; impurities of the protein, a polysaccharide and the like can be effectively removed; moreover, PVP40 (Polyvinyl Pyrrolidone 40) in the Buffer A can be used for effectively removing substances of the polysaccharide and polyphenol in plant tissue; the purity of the DNA is improved; the completeness of the DNA is enabled to be better; the quick extraction method can be directly used for a PCR (Polymerase Chain Reaction) and various enzyme digestion reaction; meanwhile, the quick extraction method does not need to use organic solvents of phenol chloroform and the like in the entire extraction process; therefore, steps of ethanol precipitation and the like do not need to be carried out; the extraction method provided by the invention, compared with a conventional extraction method, can be used for more quickly, simply and conveniently extracting the DNA; the operation, on a single sample, of the quick extraction method can be completed within 1 hour and the extraction time is greatly shortened.

The invention discloses a method for extracting edible mushroom DNA. The method comprises the following steps: (1) getting material: putting edible mushroom hyphae into a buffer solution; (2) heating: heating at the temperature of 90 to 110 DEG C; (3) centrifuging: centrifuging at the speed of 7000 to 9000 rpm for 5 to 10 min, and then extracting a supernatant liquor, wherein the supernatant liquor contains total DNA. The method for extracting the edible mushroom DNA is short in used time, simple and convenient to operate, low in cost and free from contamination to the environment, the prepared DNA is good in integrality and suitable for PCR reaction.

The invention discloses an amino acid buffer solution and a plasma free DNA extraction kit. The plasma free DNA extraction kit comprises the agents of a lysis solution, a proteinase K working liquid,an amino acid adsorption buffer solution, a washing solution, and a TE eluent; the amino acid adsorption buffer solution comprises 80-200 mM of amino acids, 0.1-0.3 M of a chaotropic salt, 5-15% of PEG (polyethylene glycol), 0.5-1.2 M of sodium chloride, 40-100 mM of Tris-HCl, and 20-50 mM of EDTA (ethylenediaminetetraacetic acid), and has pH of 2.1-2.4. the amino acids are combined with the chaotropic salt having a low concentration; pH of the buffer solution is controlled; therefore, extraction efficiency is improved. The use of PEG helps reduce shear injury of DNA and ensure DNA integrity.Therefore, extraction of free DNAs in plasma is free of inhibitor residue, has high quality, is simple to perform, and has low cost.

The invention provides a method for simply and quickly purifying genomic deoxyribonucleic acid (DNA) of various plant seeds by using a magnetic nano composite material. The method comprises the following steps of: performing sample lysis, namely adding 200 to 800 microliters of PVP (poly vinyl pyrrolidone) with mass-to-volume ratio of 2 to 5 percent, 2 to 5 percent of CTAB (cetyl trimethyl ammonium bromide) and beta-mercaptoethanol with volume fraction of 0.5 to 2 percent into a plant seed sample; blending, and performing full lysis for 5 to 30 min in a water bath; and adding 10 to 50 microliters of 10 mg/ml RNase solution, and thus obtaining sample lysis solution with the genomic DNA. The lysis solution is suitable for all plant seeds. The obtained genomic DNA does not contain an inhibitor which inhibits a downstream polymerase chain reaction (PCR); and DNA has high quality, high yield and high integrity.

The invention belongs to the field of plant quarantine technology research. Molecular standard sample of canker canker of rapeseed. Rape canker sore molecular standard sample is prepared from high-purity DNA extracted from canker canker sore strain. The standard sample has the following physical and chemical properties: (1) shape: pure white powder; (2) each tube Content 5μg±0.5μg; (3) DNA purity: OD260/280=1.8~2; (4) Soluble in water or TE (Tris-EDTA) buffer. The rapeseed canker sore molecular standard sample of the present invention uses the rapeseed canker sore strain isolated by the laboratory as a raw material, and is cultured in large quantities under specific conditions to extract high-purity DNA, which is subpackaged and freeze-dried to obtain the rapeseed canker sore strain. Molecular standard product, with excellent physical and chemical properties, can be detected by PCR method with specific primers, and the sensitivity can reach 10-4 times. After testing, the standard product has good DNA integrity, uniformity and stability, and can be used in import and export testing as a positive reference substance to improve the accuracy of test results.

The invention relates provides a reagent for extracting total DNA of lucid ganoderma and the application of the reagent. The total DNA is rapidly and efficiently extracted from about 50 mg of myceliumand sporocarp sample by adopting the steps of crushing, cracking, DNA adsorption, rinsing, eluting and the like; for fresh dry samples, and total DNA suitable for ITS identification and other molecular biology experiments also can be extracted. Further experiment proves that the method also can be applied to edible-medicinal fungi such as cordyceps militaris, agaricus blazei murill and grifola frondosa. According to the method, the extraction time of single sample is shortened to 15 minutes; in addition, the extracted DNA has the advantages of good integrity and high purity, and can be directly used for downstream molecular biology experiments such as PCR, Real-Time PCR and molecular markers.

The invention provides a DNA sulfite conversion treatment method. The method comprises the following steps of (a) preparing a DNA solution to be treated; (b) adding a conversion agent and a protectionagent into the DNA solution, and mixing to obtain a DNA mixed solution, wherein the conversion agent is a water solution of at least one of materials selected from sodium metabisulfite, sodium hydrogen sulfite, amine hydrogen sulfite, magnesium bisulfite and ammonium sulfite; the protection agent is a water solution of at least one of ingredients of hydroquinone and water-soluble vitamin E and mycose or agarose; (c) converting the DNA mixed solution under the specified condition to obtain a DNA conversion solution. According to the disclosure, the method with the advantages that the DNA sulfite conversion can be efficiently and fast realized, and the DNA integrity can be effectively ensured can be provided.

The invention provides a reagent for extracting total DNAs of Grifola frondosa and an application thereof. Total DNAs are fast and efficiently extracted from about 50mg of mycelium and sporocarp samples of Grifola frondosa through crushing and cleavage, DNA adsorption, rinsing and elution. The extraction time of a single sample is shortened to 15min, and the extracted DNAs have good integrity andhigh purity and can be directly used for downstream molecular biology experiments such as PCR, Real-Time PCR and molecular labeling. The toxic reagents such as chloroform, phenol and beta-mercaptoethanol are not used in the whole extraction process so that the researchers are protected from toxic reagents.

The invention discloses an E-cadherin methylation detection method based on a hydrosulphite sequencing method. The E-cadherin methylation detection method includes the steps that firstly, rats which are 6-7 weeks old are selected, the kidneys of the killed rats are collected, connective tissue is sheared off, the renal cortex is taken and sheared into 50-100 mg tissue fragments, and the tissue fragments are quick-frozen with liquid nitrogen and stored in a -80 DEG C refrigerator; secondly, genome DNA is extracted with a genome DNA extraction reagent kit; thirdly, the concentration and purity of genome DNA are measured with a nucleic acid quantometer, the integrity of genome DNA is detected through 0.5%-1.0% sepharose gel electrophoresis, and DNA samples detected to be qualified are placed in a -20 DEG C--80 DEG C refrigerator for use; fourthly, genome DNA is modified with a methylation conversion reagent kit, and the concentration of modified genome DNA is determined with the nucleic acid quantometer; fifthly, PCR amplification is carried out under different experiment conditions; sixthly, samples used in follow-up steps are selected in the fifth step. By means of the E-cadherin methylation detection method, the success rate of E-cadherin methylation experiments is increased.

The invention discloses a traditional Chinese medicine bulbus fritillariae cirrhosae DNA extraction reagent. The extraction reagent comprises a nuclear lysis solution, a CTAB buffer solution and a TEBuffer, wherein the nuclear lysis solution comprises Tris-HCl, EDTA, NaCl, PVP-40 and beta-mercaptoethanol, and is similar to the CTAB buffer solution in component. The DNA extraction reagent is suitable for extraction of traditional Chinese medicine bulbus fritillariae cirrhosae DNA, the removal rate of secondary metabolites is high, and the bulbus fritillariae cirrhosae DNA integrity is high. The invention further provides a traditional Chinese medicine bulbus fritillariae cirrhosae DNA extraction method. By adopting the extraction reagent, based on an existing CTAB method, improvement of anextraction reagent formula and optimization of extraction steps are carried out, so that high-purity and high-quality bulbus fritillariae cirrhosae total DNA can be obtained; and the extraction method is simple, easy to control and low in pollution.