25 results about "Hepes buffer" patented technology

This invention discloses a dual-emission molecularly imprinted ratiometric fluorescence sensor, its preparation method, and its application in the detection of chlortetracycline, belonging to the field of chemical sensor technology. The preparation method of this sensor includes the following steps: preparing silica-quantum dot composite nanoparticles; preparing a molecularly imprinted polymer using salicylamide as a template molecule; and using a post-mixing strategy to mix the molecularly imprinted polymer and silica-quantum dot composite nanoparticles in HEPES buffer to construct the dual-emission molecularly imprinted ratiometric fluorescence sensor. The advantages of this invention are: the dual-emission molecularly imprinted ratiometric fluorescence sensor provided by this invention exhibits rich fluorescence color changes, enabling rapid, highly sensitive, and visual detection of chlortetracycline; and the entire detection process is simple, convenient, and fast, making it suitable for widespread application in practical applications.

The application relates to the technical field of medical nanobiomaterials, and provides a preparation method of a GOX-CAT-HAase-Hb natural enzyme nanogel for pancreatic cancer starvation treatment, which solves the key problems of complex nanocarrier process, low enzyme encapsulation rate, insufficient drug loading, poor dispersibility, easy degradation and inactivation of free enzymes, low synergistic efficiency and poor biocompatibility in the pancreatic cancer starvation treatment; the method comprises the following steps: S1, polyallylamine is dissolved in a HEPES buffer solution, PEG2000-NHS is reacted at room temperature, glycidyl methacrylate is reacted at 60 DEG C, and a positive polymer solution is obtained through dialysis; S2, GOX, HAase, CAT and Hb are respectively modified by NAS acrylation, and are freeze-dried after dialysis and purification; S3, the four are mixed in a molar ratio of 1:1:1:1, positive polymer and acrylamide monomers are added, an initiator is added after nitrogen deoxygenation, polymerization is carried out, and a natural enzyme nanogel is obtained through dialysis and purification.

The invention discloses a preparation method and application of an aromatic dicarboxylic acid-terbium complex fluorescent sensor array. The fluorescent sensor array comprises three fluorescent probes, the terbium complexes are respectively a 5-methoxy isophthalic acid-terbium complex, a 5-hexadecyloxy isophthalic acid-terbium complex and a 5-(6 '-cholesterol) hexyloxy isophthalic acid-terbium complex, and the preparation method comprises the following steps: (1) dissolving an aromatic dicarboxylic acid ligand in DMSO (dimethylsulfoxide) to obtain an aromatic dicarboxylic acid ligand mother solution; dissolving a terbium source in distilled water to obtain terbium ion mother liquor; and (2) adding the terbium ion mother liquor into an HEPES buffer solution, adding an aromatic dicarboxylic acid ligand mother liquor into the HEPES buffer solution, and carrying out constant-temperature reaction at 30-40 DEG C for 40-95 minutes to obtain the aromatic dicarboxylic acid-terbium complex. The fluorescent sensor array can be used for detecting tetracycline, cefixime, chloramphenicol and ciprofloxacin, and is high in accuracy and sensitive.

The invention belongs to the technical field of karyotype analysis of chromosomes, and particularly relates to a cell pretreatment solution for karyotype analysis and preparation of chromosomes and application of the cell pretreatment solution. The cell pretreatment solution comprises the following components: 15 mmol / L Hepes buffer solution with the pH value of 7.2-7.6, 0.08-1.2 [mu] g / mL of vinblastine, 0.1-0.5 v / v% of Triton X-100 and 1-2 mmol / L of EDTA (Ethylene Diamine Tetraacetic Acid), and is a cell pretreatment solution with low toxicity, better dyeing effect and good cell type universality. When the cell pretreatment liquid is used for preparing a chromosome specimen, the preparation time is remarkably shortened, not only can more metaphase cell division phases be obtained, but also the proportion of the division phases capable of being used for chromosome analysis is greater than 83%, and the efficiency of karyotype analysis is remarkably improved. Meanwhile, the prepared chromosome specimen is clear in structure number, good in form, high in dispersity and few in background impurities, and the accuracy of chromosome karyotype analysis is remarkably improved.

This invention belongs to the field of exosome preservation technology and discloses a stabilizer composition for exosome cryopreservation and its application. The stabilizer composition for exosome cryopreservation provided by this invention consists of the following components and their amounts: phytosphingosine: 0.1%-0.2%; cerebroside sulfate: 0.05%-0.1%; trehalose: 2%-5%; lipid-soluble antioxidant: 0.01%-0.05%; HEPES buffer: 10-20 mM; metal ion chelating agent: 0.01%-0.05%. The composition of this invention forms a "gradient protection" through the membrane insertion of phytosphingosine and the shallow negative charge shielding of cerebroside sulfate, enabling stable cryopreservation of exosomes for more than one week with a bioactivity retention of >85%. This preservative is animal-free, easy to use, and effective, making it suitable for the clinical translation and practical application of exosomes.

The invention provides application of a cross-linking reagent in capturing nucleic acid of a biological sample fixed by an aldehyde reagent. The decrosslinking reagent comprises a denaturing agent and a buffer solution; wherein the denaturant is selected from at least one of a compound shown as a formula (I) and salt substances thereof; the buffer solution is selected from at least one of a sodium citrate-sodium chloride buffer solution, a phosphate buffer solution, a Tris-HCl buffer solution and an HEPES buffer solution. The decrosslinking reagent can eliminate connection between protein and nucleic acid in a biological sample fixed by an aldehyde reagent, unfold a nucleic acid chain and reduce the melting temperature, so that the capture efficiency of cells and the capture number of genes are improved.

The invention belongs to the technical field of biological detection, and particularly relates to a heparin binding protein detection kit as well as a preparation method and application thereof. The kit comprises a sample treating agent, a reagent R1, a reagent R2, a calibration product, a quality control product, matched excitation liquid, cleaning liquid and the like. The sample treatment agent contains a multi-component synergistic system including an HEPES buffer solution, carrageenan, polyoxyethylene octyl phenyl ether and the like, the reagent R1 is streptavidin modified magnetic nanoparticles, and the reagent R2 is an NSP-DMAE-NHS labeled HBP antibody. The kit is based on a magnetic particle chemiluminescence method, supports direct detection of plasma and whole blood, and does not need complex pretreatment. The kit is high in detection sensitivity, strong in anti-interference capability and excellent in intra-batch and inter-batch precision, can rapidly and accurately quantify the HBP concentration, can be used for early diagnosis of infectious diseases, illness state monitoring and treatment guidance, is adaptive to emergency treatment, bedside detection and other scenes, is controllable in cost and convenient to operate, and has important clinical application value.

The invention belongs to the field of chemical detection, and discloses a fluorescent probe P1, a preparation method thereof and application of the fluorescent probe P1 in spermidine and viscosity dual-function detection. The structural formula of the fluorescent probe P1 is shown in the specification. The recognition performance of the probe P1 in various common analytes in a DMF-HEPES buffer system is researched through a fluorescence spectrophotometer. Results show that the probe P1 has specific fluorescence recognition performance on spermidine, can overcome interference of other common analytes, and has a wide pH value application range. The probe has relatively good sensitivity on the recognition of spermidine, and the lowest detection limit is 0.213 mu M. In addition, the probe P1 has a good response effect on the viscosity of the solution, is not interfered by the polarity of the solution, and can realize quantitative detection of the viscosity. The results show that the probe P1 has wide application prospects in the fields of food safety, environmental detection and biology.

The invention relates to a preservation method and a preservation solution of exosomes, and belongs to the technical field of biology, the preservation solution comprises trehalose, cane sugar, sodium hyaluronate, polyethylene glycol, dextran sulfate, an HEPES buffer solution and mannitol, the preservation method comprises the following steps: mixing purified exosomes with the exosome protection solution to obtain a mixture, and adding the mixture into the exosome protection solution to obtain the exosome preservation solution. Sub-packaging the mixture, and directly cryopreserving the sub-packaged sample at the temperature of-80 DEG C or lower; in a word, through a rigid network formed by the sodium hyaluronate and the polyethylene glycol, the aggregation and fusion of the exosome in the freezing and thawing process are effectively inhibited. The embodiment shows that after three times of freeze-thaw cycles, the particle size change rate of the exosome is less than 6%, and the particle recovery rate is close to 90%.

The invention relates to the technical field of 89Zr labeled nano antibodies, in particular to a high-stability mechanical arm based on an 89Zr labeled nano antibody. The device comprises a guide pipe frame and a supporting table fixedly connected to the bottom of the guide pipe frame, a neutralizing assembly and a heating assembly are arranged above and below the guide pipe frame respectively, and a bearing assembly is arranged on one side of the supporting table. The flow guide pipe in the neutralization assembly is matched with six ZDV valves, liquid in and out of a first tubular cavity (Zr solution), liquid in a second tubular cavity (HEPES buffer solution) and liquid in an injection cavity can be accurately controlled, and cross contamination of different kinds of liquid is avoided; the hydraulic lifting rod drives the piston rod and the piston to move, quantitative extraction and pushing of the HEPES buffer solution are achieved through the pneumatic pushing injection technology, compared with manual operation, the mixing proportion can be accurately controlled, and it is ensured that the Zr solution and the buffer solution are mixed according to the preset dosage; meanwhile, the micro circulating PH electrode at the output end of the first tubular cavity can monitor the pH value of the mixed liquid in real time, and manual sampling detection is not needed.

The invention provides an Escherichia coli culture medium capable of efficiently promoting growth and a preparation method thereof, and belongs to the technical field of microbial culture mediums. The Escherichia coli culture medium per liter comprises the following components: 10 to 15 g of tryptone, 5 to 10 g of yeast extract, 2.5 to 3 g of glucose, 3 to 5 mL of glycerin, 4 to 6 g of sodium chloride, 5 to 10 g of dipotassium phosphate trihydrate, 1 to 5 g of potassium dihydrogen phosphate, 0.1 to 1 g of magnesium sulfate heptahydrate, 0.01 to 0.1 g of calcium chloride, 0.1 to 1 g of L-glutamine, 0.01 to 0.02 g of vitamin B group mixture, 0.5 to 2 g of betaine and an HEPES buffer solution, and the final concentration of HEPES is 10 mM. Compared with an LB culture medium, the escherichia coli culture medium has the advantages that the growth rate is increased by 55.6%, the recombinant protein expression quantity is increased by 59.1%, and the plasmid extraction yield is increased by 69.4%.

The invention discloses a concentrated solution for selective preservation of legionella and application of the concentrated solution, and belongs to the technical field of microbiological detection. The concentrated solution provided by the invention is formed by synergistically combining the following components: a) an HEPES buffer system; b) a selective inhibitor combination comprising glycine, a cephalosporin antibiotic, a glycopeptide antibiotic, polymyxin B and an antifungal agent; c) a legionella physiological activity protective agent composition which comprises sodium pyruvate, betaine and L-cysteine; and d) a storage stabilizer combination comprising trehalose and a chemically modified cyclodextrin. The concentrated solution disclosed by the invention can efficiently and selectively inhibit infectious microbes in sample collection and sample preservation stages, and meanwhile, the physiological activity of legionella is effectively protected.

The invention discloses a contact lens scratch repair preparation and application, and belongs to the technical field of contact lens scratch repair. The contact lens scratch repair preparation contains a polyhydroxy compound, a solvent is water or a buffer solution, the polyhydroxy compound comprises at least one of gallocatechin gallate, D-sorbitol, dihydroxybenzoic acid, vitamin C glucoside, hyaluronic acid and tannic acid, the concentration of the polyhydroxy compound is 1-100 mM, and the concentration of the polyhydroxy compound is 1-100 mM. The buffer solution comprises a PBS buffer solution, a boric acid borax solution, a Tris buffer solution and an HEPES buffer solution. The contact lens scratch repairing preparation contains the polyhydroxy compound, the contact lens is soaked in the repairing preparation, scratch repairing of the contact lens is achieved through dynamic hydrogen bonds in a system, the service life of the contact lens can be prolonged, meanwhile, the eye surface health problem caused by contact lens scratches is expected to be solved, and the contact lens scratch repairing preparation is worthy of popularization and application. And the method has a very good application prospect.

The invention discloses a benzothiazole acylhydrazone zinc ion fluorescent probe as well as a preparation method and application thereof. The probe can overcome the defects of complex synthesis, low sensitivity, long response time and the like of an existing fluorescent probe for detecting zinc ions. The preparation method of the probe comprises the following steps: introducing an acylhydrazone group containing oxygen and nitrogen into a 2 # site of benzothiazole to synthesize 1, 3-benzothiazole-2-carbohydrazide, and carrying out condensation reaction on the 1, 3-benzothiazole-2-carbohydrazide and 1-hydroxy-2-naphthaldehyde under a liquid phase condition to prepare the probe. The benzothiazole acylhydrazone zinc ion fluorescent probe prepared by the invention can identify zinc ions by naked eyes in a DMSO / HEPES buffer solution (V: V = 9: 1, the concentration of the HEPES buffer solution is 10 mmol / L, and the pH value is 7.4) solution, a 1: 1 complex is formed, and the response time is about 6 s. Meanwhile, the probe shows better selectivity and stronger anti-interference capability in the process of detecting the zinc ions, and the detection limit is 9.8 * 10 <-9 > mol / L. The pH is in a range of 4-12, the probe has good detection performance on zinc ions, and trace detection of the zinc ions in a water sample can be realized in actual environmental application.

The invention relates to a culture medium for culturing human mycoplasma pneumoniae and a culture method, and belongs to the technical field of microorganisms, the culture medium for culturing the human mycoplasma pneumoniae comprises a mycoplasma culture medium and a growth promoting additive, the growth promoting additive comprises horse serum or fetal calf serum, cholesterol, penicillin sodium and an HEPES buffer solution, according to the culture medium for culturing the human mycoplasma pneumoniae, various components are simple and easy to obtain, the preparation method of the culture medium is greatly simplified, and the efficiency is improved; according to the culture method of the human mycoplasma pneumoniae, the culture mode is changed from a static state to a dynamic state, so that the culture efficiency of the human mycoplasma pneumoniae is improved, and meanwhile, the thallus yield of the human mycoplasma pneumoniae is also improved; the culture method for preparing the human mycoplasma pneumoniae is short in period, low in cost, high in culture viable organism density and high in yield, and is suitable for large-scale culture of the human mycoplasma pneumoniae.

This invention discloses alizarin / Al 3+ Application of alizarin / Al ratio fluorescent probe in ciprofloxacin detection 3+ The ratiometric fluorescent probe is composed of alizarin solution, AlCl3 solution, and HEPES buffer. In the presence of ciprofloxacin, upon excitation with light at a wavelength of 355-365 nm, it exhibits red fluorescence at 647-653 nm and blue fluorescence at 433-439 nm. Using red fluorescence as a reference signal and blue fluorescence as a response signal, the ratio of the two fluorescence signals shows a linear relationship with the concentration of ciprofloxacin, which can be used for the quantitative detection of ciprofloxacin. Furthermore, the alizarin / AlCl3 solution... 3+ The ratiometric fluorescent probe changes color from red through purple to blue as the concentration of ciprofloxacin increases, enabling semi-quantitative visual detection of ciprofloxacin. This alizarin / Al 3+ The base ratio fluorescent probe has excellent selectivity and anti-interference ability, which can realize the visual detection and quantitative analysis of ciprofloxacin residues in eggs with good sensitivity and high accuracy.

Disclosed are: lactobacillus bacteria that satisfy at least one selected from the group consisting of the following (A) and (B); and a composition containing the lactobacillus bacteria. (A) In a culture supernatant obtained by inoculating a DMEM medium with RAW264.7 cells to achieve 5.0×105 cells / mL, adding lactobacillus bacteria to achieve a final concentration of 10 µg / mL, and culturing the same for 24 hours at 37°C and at a CO2 concentration of 5 vol%, the IL-10 concentration is 4500 pg / µL or more. (B) When the lactobacillus bacteria at a concentration of 10 µg / mL is brought into contact with Dectin-2 at a concentration of 10 µg / mL in a 15 mM HEPES buffer having a pH of 7.2 and containing 0.5 mM of CaCl2 and 150 mM of NaCl, the proportion of the number of the lactobacillus bacteria bonded to the Dectin-2 is 5% or more.

The invention discloses a multichannel fluorescent probe compound based on pyrone functionalization. The compound is synthesized through the steps of diazotization, cyclization, condensation and the like of raw materials such as paranitroaniline, furaldehyde, 2-hydroxy-1-naphthaldehyde and the like. Q3 has high selective recognition capability on Cu, and in a DMSO / HEPES buffer solution, Cu can enable fluorescence of a probe solution to be quenched, ultraviolet absorption to be subjected to red shift and the color to be changed from light green to yellow, so that fluorescence and naked eye detection are realized; the formed Q3-Cu complex can specifically recognize CN, so that fluorescence recovery, ultraviolet absorption blue shift and turning of color back to light green are caused, and Cu and CN can be continuously detected. The probe can be used for Cu / CN fluorescence imaging in living cells, detection of Cu residues in traditional Chinese medicinal materials and preparation of Cu / CN detection test paper, and has the characteristics of high sensitivity, strong anti-interference performance, quick response and the like.

This application belongs to the field of detection technology and relates to a kit for detecting creatine kinase isoenzymes and its application, including a first detection reagent and a second detection reagent; the first detection reagent includes Hepes buffer, NaCl, PEG-6000, nonylphenol polyoxyethylene ether, BSA, NaN3, a chemical blocking agent, and a biological blocking agent; the second detection reagent includes CKMB sensitized latex particles, Hepes buffer, a blocking agent, Tween-20, and NaN3. This application effectively improves the detection sensitivity of creatine kinase isoenzymes.

The application belongs to the technical field of in vitro diagnostic reagents, and discloses a cleaning solution for acridinium ester chemiluminescence immunoassay of allergens, a preparation method and application thereof. The cleaning solution is composed of HEPES buffer, a triple surfactant system (poloxamer 188, sodium deoxycholate and octyldecyl glucoside), glycerol, PEG8000, disodium EDTA and a composite preservative of Proclin 950 and BHT. The triple surfactant synergistic system is adopted to reduce non-specific adsorption, the HEPES weak alkaline buffer system avoids the inhibition of phosphates on acridinium ester luminescence, and the composite preservative system solves the toxicity and stability problems of traditional preservatives. The cleaning solution can significantly reduce the background luminescence value, the inhibition rate of hemolysis / lipemia / jaundice interference is less than 5%, the detection accuracy deviation is within ±5% (r>0.99), the precision is less than 3.5%, and the room temperature stability is more than 13 months, and the comprehensive performance is better than that of the commercially available products.

The present invention belongs to the technical field of pharmaceutical preparations, and specifically relates to an irinotecan hydrochloride liposome, and a preparation process therefor and the use thereof. The preparation process of the present invention comprises the following steps: (1) adjusting the concentrations of triethylammonium sucrose octasulfate in an internal aqueous phase and the total lipids, and mixing an oil phase and an aqueous phase at a certain flow rate and ratio by means of a microfluidic device to prepare a blank liposome; (2) removing free triethylammonium sucrose octasulfate and organic solvent outside the blank liposome by using an HEPES buffer, and performing concentration; and (3) preparing a drug-loaded liposome by using an active loading method. The solution of the present invention can greatly improve the encapsulation efficiency of the irinotecan hydrochloride liposome and accurately control the particle size of the liposome. The finally prepared liposome has a particle size of 90 nm-115 nm, an encapsulation efficiency of 95%, and a better stability.

The invention discloses a dual-emission molecular imprinting ratiometric fluorescence sensor, a preparation method thereof and application of the dual-emission molecular imprinting ratiometric fluorescence sensor in aureomycin detection, and belongs to the technical field of chemical sensors. The preparation method of the sensor comprises the following steps: preparing silicon dioxide-quantum dot composite nanoparticles, and preparing a molecularly imprinted polymer by taking salicylamide as a template molecule; and mixing the molecularly imprinted polymer and the silicon dioxide-quantum dot composite nanoparticles in an HEPES buffer solution by adopting a post-mixing strategy to construct the dual-emission molecularly imprinted ratiometric fluorescence sensor. The double-emission molecular imprinting ratiometric fluorescence sensor has the beneficial effects that the double-emission molecular imprinting ratiometric fluorescence sensor provided by the invention is rich in fluorescence color change, rapid, high-sensitivity and visual detection of aureomycin can be realized, the whole detection process is simple, convenient and rapid, and the double-emission molecular imprinting ratiometric fluorescence sensor is suitable for being widely popularized in practical application.

This application provides a method for establishing and applying mouse gastric squamous cell carcinoma cell lines and gastric cancer-related fibroblast cell lines. The culture medium for culturing these cell lines comprises L-WRN cell culture supernatant, and 100×N-2 additive (0.5 vol%–1.5 vol%), 50× vitamin A-free B-27 additive (1.5 vol%–2.5 vol%), N-acetylcysteine ​​amide (1 mM–1.5 mM), nicotinamide (8 mM–12 mM), FGF-10 (80 ng / mL–120 ng / mL), EGF (40 ng / mL–60 ng / mL), A83-01 (0.8 μM–1.2 μM), Y-27632 dihydrochloride (8 μM–12 μM), Glutamax additive (0.5 vol%–1.5 vol%), and Matrigel. The culture medium provided in this application contains 5 vol%–7 vol% Hepes buffer (8 mM–12 mM) and gastrin (0.8 nM–1.2 nM). This medium can significantly improve the success rate of in vitro culture of primary cell lines. The mouse gastric squamous cell carcinoma cell lines and gastric cancer-related fibroblast cell lines obtained from this medium are genetically stable and can be used to construct ectopic or orthotopic implantation models in immune-active mice.

The invention provides cellobiose phosphorylase as well as a construction method and application thereof, the cellobiose phosphorylase starts from wild type cellobiose phosphorylase, and a mutant library of the cellobiose phosphorylase is constructed by using error-prone PCR (Polymerase Chain Reaction) with low mutation rate; a mutant library inserted into plasmid pET28a is transferred into host Escherichia coli BL21 (DE3) and coated on a flat plate, modified cellobiose phosphorylase is obtained, the amino acid sequence of the modified cellobiose phosphorylase is shown as SEQ ID NO: 2 in a sequence table, cellobiose can be subjected to phospholysis into glucose-1-phosphoric acid and glucose, in the application process, cellobiose mother liquor is taken, and the modified cellobiose phosphorylase can be used for preparing glucose-1-phosphoric acid and glucose. And adding an HEPES buffer solution, a phosphate buffer solution and pure water, adding the crude enzyme solution of the cellobiose phosphorylase, and reacting at 60 DEG C. The cellobiose can be used for producing the glucose-1-phosphoric acid, the conversion rate of the reaction time in 10 hours is greater than 90%, and the method is suitable for industrially preparing the glucose-1-phosphoric acid.

This invention discloses a colorimetric detection method for histamine and spermine based on Pro-Ag nanozyme-mimicking laccase activity. The method involves first plotting standard absorbance curves for histamine and spermine, then constructing linear regression equations to determine the relationship between the concentrations of histamine and spermine and their absorbance values. The concentrations of histamine and spermine in the sample are then determined using these linear regression equations. This invention is the first to apply the laccase-mimicking activity of Pro-Ag nanozymes to the detection of biogenic amines. In HEPES buffer solution, histamine and spermine can inhibit the laccase activity of Pro-Ag nanozymes, causing the reaction solution to appear light pink, thus enabling rapid detection.