33results about How to "Do not interfere with determination" patented technology

The invention relates to the detection of tripolycyanamide, in particular to a method and a device for detecting tripolycyanamide. The method comprises: preprocessing a sample to be detected to remove proteins; allowing obtained clear liquid to pass through an anionic and cationic ion exchange series column at a constant flow rate; transferring the clear liquid to be detected and buffer solution into a cell for samples to be detected; inserting an ion selective electrode modified by a molecular imprinted polymer into the cell; generating an electric potential signal; and determining the tripolycyanamide content of the sample to be detected by using an electric potential value according to a standard curve. In the device, one end of the anionic and cationic ion exchange series column, a second flow injection device and a container for the samples to be detected are connected with a three-way valve respectively; the other end of the anionic and cationic ion exchange series column is connected with an ultramicropore protein filter through a first flow injection device; and the second flow injection device is connected with a buffer solution tank; and the ion selective electrode modified by the molecular imprinted polymer is inserted into the container for the samples to be detected. The method and the device have the advantages of high flexibility, low operation cost, suitability for in-situ monitoring and the like in the detection of tripolycyanamide.

The invention discloses a separation and detection method of an acetylcysteine enantiomer. The method comprises the following steps: performing derivatization reaction in an organic solvent by using aderivatization reagent, N-acetyl-L-cysteine and an enantiomer thereof, so as to prepare a derivative product of N-acetyl-L-cysteine and isomers thereof; and performing separation and detection by using normal phase high-performance liquid chromatography, wherein the derivatization reagent is isocyanate. According to the separation and detection method of the acetylcysteine enantiomer, the derivatization reagent, N-acetyl L-cysteine and the enantiomer thereof are reacted, so that the mutual attraction effect between the stationary phase in the chromatographic column and the chiral substance tobe separated is increased according to the chiral separation mechanism by adopting precolumn derivatization normal phase high-performance liquid chromatography, and the chiral separation selectivityis effectively improved. The method is simple and convenient to operate, short in consumption time and easy to popularize and use.

The invention relates to the technical field of solvent residual detection of drugs, and concretely relates to a method for detecting residual solvents in heparin sodium by headspace gas chromatography. The method optimizes the headspace sampling balance temperature which is an important parameter affecting the peak area ratio of the analytes to an internal standard by adopting the headspace gas chromatography against the technical problem of poor system adaptability of methods for detecting the residual solvents in the heparin sodium in the prior art, and the headspace balance temperature isoptimized to 78-82 DEG C from 90 DEG C. The method for detecting residual solvents in heparin sodium by headspace gas chromatography allows the relative standard deviation of the peak area ratio of the analytes to the internal standard during the repeated introduction of a control to be less than 1.0% and the system applicability to meet requirements, has the advantages of good specificity, good resolution of the analytes, good repeatability and high sensitivity, the detection limit of methanol is 0.0008%, the detection limit of ethanol is 0.0002%, the detection limit of acetone is 0.0001%, the quantitation limit of methanol is 0.0023%, the quantitation limit of ethanol is 0.0007%, and the quantitation limit of acetone is 0.0003%.

The invention provides a coumarin derivative DOCOPA as well as a preparation method and an application thereof. The English name of DOCOPA is (E)-4-(3-(7-(diethylamino)-2-oxo-2Hchromen-3-yl)-3-oxoprop-1-en-1-yl) phenylacrylate). The preparation method comprises the steps that 3-acetyl-7-diethylaminocoumarin and p-hydroxybenzaldehyde are dissolved in acetonitrile firstly, a catalytic amount of piperidine is added, and reflux is performed until a reaction is performed sufficiently; an intermediate compound is further obtained; the intermediate compound and triethylamine are dissolved in dichloromethane, acryloyl chloride is added dropwise gradually to an ice bath, room-temperature stirring is performed until a reaction is performed sufficiently, a product is subjected to column chromatography separation after reduced-pressure evaporation, and the DOCOPA is obtained. The DOCOPA is applied to distinguishing and detection of cysteine and homocysteine in a pH7.8 system and imaging of the cysteine and the homocysteine in cells. The DOCOPA shows high sensitivity and selectivity for the cysteine and the homocysteine.

The invention provides a method capable of detecting cysteine in a half-aqueous solution. Importantly, the method can distinguish cysteine from homocysteine. Based on a complex dichlorotetra[2-(2-pyridyl)phenyl]diiridium(III)[Ir2(ppy)4Cl2], in the half-aqueous solution of DMF (dimethylformamide) or DMSO (dimethylsulfoxide), the cysteine is directly detected by a fluorescent method. The determination process is simple and convenient and free from the interference of other amino acids including homocysteine and anions in the solution; and the method can be used for detecting whether cysteine exists or not.

The invention provides a method for detecting a content of heavy metals, which belongs to the technical field of the detection of metal ions. The method comprises the following steps: (1) preparing asolution to be detected: preparing a heavy metal sample to be detected into an aqueous solution, adding an acidic solution and a potassium iodide solution, and obtaining the solution to be detected; (2) detecting the solution to be detected: moving the solution to be detected, dropwise adding the solution to be detected onto test paper, developing the color for 50s to 100s, wherein the test papercontains dye; and (3) judging a detection result: visually comparing the color developing test paper and a colourimetric card, and determining a concentration of the heavy metal. By adopting the method for detecting the heavy metals, a rapid detection effect can be achieved, the detection efficiency is increased, and the field operation is also facilitated.

The invention relates to a super fast liquid phase chromatography-tandem mass spectrometric method for determining hydroxypropyl-beta-cyclodextrin. The method comprises the following steps: (1) preparing hydroxypropyl-beta-cyclodextrin standard curve solution; (2) preparing hydroxypropyl-beta-cyclodextrin quality control solution; (3) treating a sample; and (4) performing liquid phase chromatography-tandem mass spectrometric analysis on the standard curve solution and the quality control solution respectively, and establishing a method for determining the hydroxypropyl-beta-cyclodextrin in thesample solution. The method has simple operation and good reproducibility, and can quantitatively analyze HP-beta-CD.

The invention discloses an ultraviolet absorption measurement method for waste gas sulfur dioxide of a stationary pollution source. According to the method, an ultraviolet absorption method sulfur dioxide analyzer or multiple groups of gas analyzers with an ultraviolet absorption method sulfur dioxide analysis function is/are used as multiple monitors; sulfur dioxide is used for absorbing light with the characteristic wavelength of 240-330nm in a near ultraviolet light region, and the concentration of sulfur dioxide in waste gas is quantified according to the lambert-beer law; then the sulfur dioxide discharging rate is obtained by further calculation. An ultraviolet absorption method can adapt to wider measurement on SO2 discharged by the stationary source; by the method, the requirements on supervising monitoring on an on-site pollution source, comparison monitoring on a CEMS (continuous emission monitoring system) and checking of data effectiveness are met.

The invention discloses a detection method of the content of vitamin C in a vinpocetine injection. The detection method comprises the following steps: carrying out spectrum scanning through an ultraviolet-visible spectrophotometer to determine the maximum absorption wavelength lambdamax of a vitamin C standard solution; then preparing one group of vitamin C solutions with different concentrations and determining a chromatographic peak area of each vitamin C solution through a high performance liquid chromatograph under the maximum absorption wavelength lambdamax; drawing a standard curve of the vitamin C solutions and the corresponding chromatographic peak areas and solving a linear regression equation; meanwhile, determining a chromatographic peak area of a test sample solution through the high performance liquid chromatograph under the maximum absorption wavelength lambdamax; and finally, calculating the content of vitamin C in the test sample solution. According to the detection method disclosed by the invention, the content of vitamin C in the vinpocetine injection is detected by adopting an HPLC (High Performance Liquid Chromatography) method; and the detection method is simple, convenient and feasible, has high specificity and high accuracy and provides guarantees for safety, effectiveness and controllability of drugs.

The invention discloses an arsenic-free detection method of iodide ions in a trace serum sample for individual iodine nutrition evaluation. The arsenic-free detection method overcomes the defect thata highly toxic reagent is used in an existing method, adopts a sodium chlorate-sulfuric acid solution for digesting the serum sample at the temperature of 110 DEG C, uses iodine catalyzing the reduction reaction of sodium nitrite and ferric thiocyanate, and measures a concentration change speed of Fe(SCN)6<3-> to be in direct proportion to the iodine content; the reaction temperature and the reaction time are precisely controlled, the absorbance of the remaining Fe(SCN)6<3-> is measured, and the iodine content and the logarithm of the absorbance are in a linear relation. The establishment of the arsenic-free detection method can further meet the gradually increased demand of people for knowing the iodine nutrition level, a powerful method and means are added to serum iodine detection of iodine deficiency disease prevention and treatment monitoring and iodine nutrition evaluation, and the arsenic-free detection method has important public health practical significance and practical application value.

The invention discloses an arsenic-free detection kit for iodide ions in a trace serum sample. According to the arsenic-free detection kit, the defect that a highly toxic reagent is used in the priorart is overcome, a sodium chlorate-sulfuric acid solution is used for digesting a serum sample at 110 DEG C, iodine is used for catalyzing the reduction reaction of sodium nitrite and ferric thiocyanate, and the concentration change speed of Fe(SCN)6<3-> is measured to be in direct proportion to the iodine content; the reaction temperature and the reaction time are precisely controlled, the absorbance of the remaining Fe(SCN)6<3-> is measured, and the iodine content and the logarithm of the absorbance are in a linear relation. An existing serum iodine quantitative determination method has thedefects of complex reagent preparation, easiness in pollution and decomposition, large dosage of dangerous reagents and large required serum amount. The arsenic-free serum iodine detection kit researched by the invention is convenient to operate, easy to carry, high in safety and suitable for clinically developing individual iodine nutrition detection.

The present invention relates to a method for sensitively detecting tannin acid (TA) in beer. The method comprises the steps of: taking graphene oxide (GO) and ammonia water (NH3.H2O) as raw materials, and performing hydrothermal cutting under a strong alkaline condition to prepare amination GQDs (AF-GQDs). The polyphenolic hydroxyl structure of TA enables hydrogen bonding between the TA and the AF-GQDs, and a strong pi-pi interaction can be generated, so that fluorescence quenching of AF-GQDs is caused. A TA quantitative analysis method is established by using the AF-GQDs as a fluorescent probe, and the detection limit is 43.3 nmol/L<-1>; and the method has strong anti-interference ability, and detection of the TA is not interfered by the common small molecules, metal ions, anions, and the like.

The invention discloses a method for rapidly and efficiently detecting trace p-phenylenediamine. The method specifically comprises the following steps of dissolving cotton cellulose to prepare a regenerated cellulose membrane; selectively oxidizing hydroxyls on the regenerated cellulose membrane into aldehyde groups by adopting sodium periodate; and carrying out a two-step Schiff base reaction toprepare a solid-phase fluorescence detection membrane of each system for emitting yellow fluorescence, wherein the solid-phase fluorescence detection membrane is used for qualitative analysis and quantitative detection of the phenylenediamine. The method has the advantages of simplicity and quickness, high sensitivity and good selectivity.