1430 results about "Detection limit" patented technology

The invention provides an online quality detection method of a nerve-soothing and brain-nourishing liquid based on multispectral fusion, and aims at solving the bottleneck problems of long offline time consumption, weak multi-index detection capability, poor dynamic adaptability and the like in the traditional detection technology, and realizing intelligent quality control of the whole process of the production technology. The device integrates an ultraviolet-visible spectrum module, a near-infrared spectrum module and a fluorescence spectrum module, constructs a multi-scale residual convolutional network to extract near-infrared spectrum characteristics, analyzes a fluorescence excitation-emission matrix through bidirectional LSTM, and cooperates with dynamic baseline correction of an ultraviolet spectrum, so that the icariin content detection precision is improved by 40% compared with that of a traditional HPLC method, the heavy metal residue detection lower limit reaches 0.05 ppm, and the detection accuracy is greatly improved. And an innovative solution is provided for intelligent production of traditional Chinese medicine preparations.

The invention discloses a high-sensitivity carbendazim detection method based on terahertz metamaterial resonance enhancement, and provides a terahertz metamaterial sensor with a cross-shaped composite double-peak structure, a terahertz spectrum technology is utilized to collect transmission spectrums, the difference of different concentrations among terahertz spectrums is explored, and the detection accuracy is improved. The analysis finds that the transmission peak amplitude of the terahertz transmission spectrum of the structure is in a decreasing trend along with the increase of the concentration of a carbendazim solution, data is preprocessed through multiple scatter correction (MSC), feature extraction is performed by adopting an iterative information variable reservation (IRIV) method, and a quantitative detection model of the carbendazim terahertz transmission spectrum is established based on an LS-SVM (least squares support vector machine). The invention provides a novel approach for quantitative detection of carbendazim, and experimental results show that the RP of the model reaches 0.9825, the RMSEP is 0.2001, and the detection limit LOD is 0.672 mu g / ml. The invention provides a new method for rapid, lossless and high-sensitivity detection of carbendazim in food.

The invention relates to the technical field of analysis and detection, in particular to a micro-area distribution detection method for micro and / or trace component elements in nickel-based single crystal superalloy. According to the method, the conventional common element distribution detection means (EPMA, EDS, TOF-SIMS, TEM and EELS) are combined, the detection limit and the detection advantages are referred, different devices are reasonably utilized by analyzing different phase structure characteristics, quantitative or semi-quantitative element micro-area distribution analysis is quickly and effectively realized, the use requirements on high-precision devices are reduced, and the method is suitable for large-scale popularization and application. And the cost and the test difficulty are greatly reduced.

The invention discloses a preparation method and application of a concave-structure SERS (Surface Enhanced Raman Scattering) substrate for prostatic cancer exosome detection, and relates to the field of Raman spectrum detection. The invention aims to solve the problems that the quantity of electromagnetic field hot spots of the currently reported SERS substrate with the concave structure is small, the SERS substrate does not have good uniformity, the size is not matched with EVs, the detected EVs signal is relatively weak, and the parting detection requirement cannot be met. The preparation method of the SERS substrate with the concave structure comprises the following steps: 1, preparing a PDMS concave trap structure array; 2, preparing a concave well array of which the surface is covered with densely arranged Au NPs; according to the invention, Au nanoparticles are grown in situ in a PDMS concave structure, a concave trap array of which the size is matched with that of EVs and the surface is covered with densely arranged Au NPs is constructed, high-sensitivity detection (lower detection limit of 105 particles / mL) and high-accuracy typing of prostatic cancer EVs are realized, and the accuracy rate can reach 98% or more.

The invention belongs to the technical field of monatomic nano-enzyme material preparation, and particularly relates to a nano-enzyme preparation method for acetylcholin esterase activity detection. The Ni-NiO heterojunction material is successfully synthesized by adopting Ni-MOF as a carrier and accurately regulating and controlling the ratio of nitrogen to air in the ultrafast Joule hot calcination process. The material has rich oxygen vacancies and metal Ni sites, the oxygen vacancies and the metal Ni sites can effectively serve as anchoring sites of Pt single atoms, the loading capacity and dispersity of the Pt single atoms are remarkably improved, and therefore the excellent nano-enzyme catalytic activity is shown. In addition, the preparation method disclosed by the invention is simple and convenient in process and has a wide industrial application prospect. An acetylcholin esterase activity colorimetric sensing method constructed on the basis of the nanometer enzyme for acetylcholin esterase activity detection prepared by the method has extremely high sensitivity and low detection limit. The detection limit of the technology can be as low as 0.037 mU / mL, the problem that the sensitivity of a traditional detection method in a low-concentration sample is insufficient is remarkably solved, and remarkable clinical application potential is shown.

The invention provides a method for simultaneously detecting various micro-plastics in water, and belongs to the technical field of micro-plastic detection. The method comprises the steps of sample pretreatment, thermal cracking-gas chromatography-mass spectrometer measurement, qualitative analysis and quantitative analysis. The method comprises the following steps: taking a water sample, uniformly shaking, filtering with a filter membrane, taking the filtered filter membrane, adding acetone, carrying out ultrasonic elution, washing the filter membrane, and collecting an eluent; adding acetone into the eluted filter membrane, carrying out ultrasonic elution again, washing the filter membrane, collecting the eluent, combining the two eluents, heating and concentrating in a water bath, adding acetone, ultrasonically mixing, transferring into a cracking cup, heating and volatilizing, and determining by a thermal cracking-gas chromatography-mass spectrometer. Carrying out qualitative analysis through analysis of cracking products with different types of micro-plastic characteristics, and then carrying out quantification through an external standard method; the method provided by the invention can accurately quantify the six microplastics in the effluent, and has the advantages of simple pretreatment, small sampling amount, high accuracy and lowest detection limit of 0.012 [mu] g / L.

The invention discloses a near-infrared fluorescent probe for detecting ONOO <-> as well as a preparation method and application of the near-infrared fluorescent probe, and belongs to the technical field of peroxynitroso ion detection. The near-infrared fluorescent probe for detecting ONOO <-> provided by the invention is high in detection speed, and the highest fluorescence intensity can be reached within 60 seconds; the reaction is obvious and easy to observe, when the compound reacts with ONOO <->, strong red fluorescence can be generated, and the change of the color of the solution can be observed by naked eyes; the selectivity is strong, the sensitivity is high, the interference of other biological molecules and active substances can be effectively avoided, the accuracy and the reliability of a detection result are ensured, and the lowest detection limit can reach 107nM; the hydrogel has good biocompatibility, is low in toxicity in a living body, and does not generate adverse effects on normal physiological functions of a biological sample; the provided preparation method is simple and easy to operate, the raw materials are low in cost and easy to obtain, the synthesis efficiency is high, and the preparation method can be used for large-scale industrial production and has wide application prospects.

The invention discloses a specific primer for distinguishing rice and barnyard grass and application of the specific primer, and belongs to the technical field of biological species identification. The sequences of the specific primers are as shown in SEQ ID NO. 1 and SEQ ID NO. 2. The specific primer is designed according to the nuclear gene ITS sequence of the rice, the specific primer can accurately identify the rice through PCR, the identification method is stable, the detection time is short, the specificity is high, the detection limit is low, the identification method is not affected by material characters, rapid and accurate identification of the rice and barnyard grass can be achieved, and the identification efficiency is high. The problem that a method for effectively and rapidly distinguishing rice and barnyard grass does not exist at present is solved.

The invention discloses a kit for detecting salmonella enteritidis and application of the kit, and belongs to the technical field of biomolecular detection. The kit comprises the following components: an allosteric aptamer probe of which the nucleotide sequence is as shown in SEQ ID NO.1, a template chain of which the nucleotide sequence is as shown in SEQ ID NO.3 and a fluorescence report probe of which the nucleotide sequence is as shown in SEQ ID NO.4. According to the kit, salmonella enteritidis can be distinguished from other impurities, and the specificity is high; a visual fluorescence signal can be obtained and is easy to interpret; according to the invention, a template chain can be cyclically utilized in the reaction to generate a Trigger chain to guide the TtAgo protein to efficiently and specifically cut a fluorescent reporter probe, the output signal is increased, the detection time is short, the detection limit is low, the sensitivity is high, the specificity is good, and the method has practical popularization and application prospects.

The invention belongs to the technical field of molecular identification of insects, and particularly relates to multiple PCR (Polymerase Chain Reaction) primers and a method for rapidly identifying thrips insect varieties. The invention discloses a multiple PCR primer and a method for rapidly identifying the variety of thrips, the identification primer and a multiple PCR system can rapidly, effectively and accurately identify the three types of thrips, and the sizes of PCR product strips of tobacco thrips, comb flower thrips and common large thrips are 104 bp, 237 bp and 439 bp respectively. The detection limit of the sensitive tobacco thrips is 500 copies, and the detection limits of the sensitive tobacco thrips and the sensitive common large thrips are both 100 copies. Compared with common PCR which can only identify one type of thrips at a time, the multiplex PCR system can complete identification of various types of thrips at a time, has the advantages of being easy to operate, low in cost, capable of saving time and the like, has very high value in the aspect of field thrips detection, and can be widely applied to the fields of plant protection and the like.

The invention discloses a method for accurately deducting Sr double-charge interference in in-situ Ca isotope determination, and relates to the technical field of isotope analysis. According to the method, the Sr double-charge interference in the in-situ Ca isotope measurement is accurately deducted through an iteration method, the Ca isotope measurement result can be simply and quickly corrected, and high-resolution, low-detection-limit and high-flux Ca isotope measurement is realized; ca single-charge fractionation factors are calculated through an iterative method, and instrument quality discrimination correction and accurate deduction of Sr double-charge interference are simultaneously realized through formulas 1-5 in combination with the Sr isotope ratio; the method breaks through the application limitation of in-situ Ca isotope measurement, is suitable for high-Sr and low-Sr samples, solves the technical problems of in-situ Ca isotope analysis accuracy and analysis precision, fills the technical blank of Ca isotope measurement in the Sr-rich sample in laser in-situ detection, and provides a firm technical support for application in the field of geoscience.

The present invention relates to the technical field of test and detection, and particularly to an on-line measurement method and device for total iron in power station water vapor. A catalytic reagent is added to the water sample to be measured and acts through an ultraviolet light oxidizer, so as to completely convert the colloidal iron in the water sample into ferric ions. The dissolution and conversion of the colloidal iron are completed without adding acid throughout the process. Since no acid is added during the process of converting the whole colloidal iron into dissolved iron, only a chromogenic reagent needs to be added to accurately measure the total iron content in the water sample, and it is also easier to realize the on-line measurement of total iron in the water sample. When the total iron content in the water sample is less than 10 μg / L, the water sample enters the concentration system for concentration and then optical measurement, so that the low-concentration total iron in the water sample can also be accurately measured. This measurement method can automatically measure the total content in the water sample on-line, avoid manual sampling and detection, can monitor the total iron in the water sample in real time, and has a lower detection limit and more accurate detection results, which is beneficial to the adjustment of the water condition during the start-up and shutdown stages of the power station.

The invention discloses a staphylococcus aureus biosensor based on a nucleic acid aptamer and a preparation method of the staphylococcus aureus biosensor. Three fluorine atoms (F) are introduced into the 5'end, the 3 'end and the middle position of an aptamer 2' F3-(5 '3'm DNA) sequence (SEQ ID NO: 1) for modification, so that the binding force of the aptamer and graphene is remarkably enhanced, the signal stability and the anti-interference capability of the biosensor are remarkably improved, non-specific fluorescence leakage can be effectively blocked, and reliable guarantee is provided for complex sample detection. According to the present invention, with the cooperation of the graphene oxide quenching substrate, the high-sensitivity detection of the staphylococcus aureus is achieved, the detection limit of the sensor within 5 min can achieve 5 cells / mL, the sensitivity is high, the specificity on the complex sample is more than 95.4%, and the sensor is suitable for the food safety rapid screening and the clinical diagnosis.

The invention relates to a preparation method and application of a novel lactic acid detection fluorescent probe, and belongs to the technical field of fluorescent probes. The preparation method of the fluorescent probe comprises the following steps: synthesizing a core-shell type up-conversion nano material CS-UCNPs; carrying out surface modification on the core-shell type up-conversion nano material CS-UCNPs; coupling of the core-shell type up-conversion nano material CS-UCNPs and an L-lactic acid aptamer is carried out; and synthesizing the magnetic molybdenum disulfide nanosheet MoS2. The L-lactic acid aptamer, the core-shell UCNPs and the magnetic MoS2 are combined for high-sensitivity detection of the lactic acid content, and compared with a traditional blood lactic acid detection method, the method has the advantages of being non-invasive, non-invasive and the like; and the technology has the advantages of simplicity in operation, high specificity, quick response and the like, has a wider detection range and a lower detection limit, and is expected to be applied to actual sample detection work.

The invention relates to an extracellular vesicle surface protein detection paper-based kit and application thereof, and belongs to the technical field of biology. The technical problems that an existing sEVs detection technology is insufficient in specificity, depends on professional instruments and cannot meet the instant detection requirement are solved. According to the method, sEVs are synergistically captured through double aptamers, the target specificity is improved, signals are amplified in a cascaded mode through hyper-branched rolling circle amplification (HRCA) and a CRISPR / Cas12a system, and visual detection is achieved by detecting FAM-biotin probe separation before and after cutting through a transverse flow test strip. According to the method, interference of free protein is effectively avoided through double-target recognition, and the detection limit is as low as 406 parts / mL; cRISPR and a paper-based technology are combined to realize high sensitivity and instant detection; the system is simple and convenient to operate, does not need professional instruments, is suitable for tumor diagnosis and treatment monitoring of clinical samples, and provides a portable solution for precise medical treatment.

The invention relates to the technical field of pesticide detection, and discloses a pesticide residue detection system for agricultural products, comprising: a high-precision detection module comprising one or more detection units adopting a high performance liquid chromatography-mass spectrometry (HPLC-MS / MS) technology, each detection unit being configured with a detection limit of not less than 1 ng / g, the resolution ratio is not lower than 0.01 ppm, and the quantitative analysis precision is high. And the intelligent data analysis software integrates a pesticide residue data analysis engine based on an artificial intelligence (AI) algorithm, and quickly and accurately judges the types and residual quantity of pesticides. And the standardized data interface and sharing platform is designed with a unified data exchange format and an interface standard. By adopting a high-precision detection module and combining a high performance liquid chromatography-mass spectrometry (HPLC-MS / MS) technology, the system realizes multi-channel parallel processing and high-sensitivity detection, ensures the accuracy of a detection result, effectively solves the problem that the detection technology and the equipment level are uneven, and improves the overall detection level.

The invention discloses a non-enzymatic uric acid electrochemical sensor based on quaternary ammonium salt modified MXene, a method and application, and belongs to the technical field of sensors. The preparation method comprises the following steps: preparing an MXene material through an etching method; the preparation method comprises the following steps: modifying an MXene material by adopting quaternary ammonium salt to obtain a modified MXene material; a working electrode is modified with the modified MXene material, a reference electrode and a counter electrode are combined to form a three-electrode system, and the non-enzymatic uric acid electrochemical sensor based on quaternary ammonium salt modified MXene is obtained. The prepared non-enzymatic uric acid electrochemical sensor is excellent in performance, high in sensitivity and low in detection limit; the linear range is wide and covers the human blood uric acid concentration range; the stability is good, and the influence by temperature and pH is avoided; the biological compatibility is good, the antibacterial property is good, and the toxicity is low. The sensor can realize rapid and quantitative detection of human blood uric acid concentration, has excellent detection performance, and has no obvious difference with the detection result of a large biochemical analysis instrument.

The invention relates to a pesticide residue detection test strip as well as a preparation method and application thereof, in particular to a rapid detection technology based on an enzyme inhibition method and a chitosan non-woven fabric carrier. The test strip can specifically detect organophosphorus and carbamate pesticides such as trichlorfon, malathion and phoxim through the enzyme activity inhibition principle, the detection limit of the pesticides such as phoxim is as low as 0.1 mg / kg, the developing intensity is in negative correlation with the pesticide concentration, and semi-quantitative judgment can be achieved. The preparation process is simple, the chitosan non-woven fabric is adopted as a fixed carrier, the material is environment-friendly and degradable, the enzyme activity recovery rate reaches 90%, the stability is excellent (the enzyme activity recovery rate can be preserved for 60 days at the temperature of 4 DEG C in a dark place), sample pretreatment is not needed in detection operation, a result can be obtained at the normal temperature for 15 min, the stability and repeatability are good, and the problems that a traditional instrument is high in detection cost and long in time consumption are solved; the method has a remarkable basic popularization value.

The invention belongs to the field of fluorescence detection, and particularly relates to a ratio-type fluorescent nanoprobe for specifically detecting tetracycline antibiotics as well as a preparation method and an application method of the ratio-type fluorescent nanoprobe. The nano-probe is a europium modified zinc gallium germanate nano-material, and is prepared by amino modification, citric acid modification and europium modification of the zinc gallium germanate nano-material. The probe can be specifically combined with tetracycline antibiotics; the fluorescent probe has two different fluorescence emission intensities, so that interference can be effectively eliminated, and the detection accuracy is high. And the synthesis method is simple and low in cost. The ratio type fluorescent nanoprobe provided by the invention also can realize the change of different colors under an ultraviolet lamp, can realize quantitative visual detection of tetracycline by combining the RGB value and the tetracycline concentration change, and can realize rapid on-site detection of tetracycline in a sample without the help of a fluorescent instrument. The tetracycline fluorescent probe is stable in optical performance, not prone to photobleaching, high in tetracycline recognition capacity, wide in response range (0.2-70 [mu] M) and low in detection limit, and has remarkable industrial application potential.

The invention belongs to the field of biomedical treatment, and particularly discloses a series of cancer cell early detection probes, a kit and a detection method. Aiming at the problems of low sensitivity, poor specificity, complex operation, long detection period and the like of the existing cancer cell detection means, various innovative probes are invented. Ten probes such as a quantum dot FRET probe based on a nucleic acid aptamer and a gold nano-cluster-antibody composite probe have different characteristics, and accurate recognition and detection of cancer cell markers are achieved through unique design principles such as aptamer screening, nano-material modification and a signal amplification strategy. Through synergistic comparison, the sensitivity of the probes is greatly improved, the lower detection limit is as low as 0.3-1.5 pg / mL and is improved by 30%-60% compared with that of a traditional method, the specificity and accuracy are high, the detection time is shortened to 1-2 hours, the sample demand is low, and the probes also have diagnosis and treatment integration and multi-mode imaging functions, and provide powerful support for early diagnosis and treatment of cancers.

The invention relates to the technical field of medicine analysis, in particular to a method for analyzing mutagenic impurities in a small molecule fungal inositol acyltransferase 1 inhibitor raw material medicine, the analysis method can be used for trace detection of potential mutagenic impurities I and II in the raw material medicine, the limit of quantitation concentration of the impurity I is not higher than 0.53 ng / ml, and the limit of quantitation concentration of the impurity II is not higher than 0.53 ng / ml. The detection limit concentration of the impurity I is not higher than 0.27 ng / ml; the quantitation limit concentration of the impurity II is not higher than 0.52 ng / ml, and the detection limit concentration of the impurity II is not higher than 0.26 ng / ml. The analysis method suitable for the mutagenic impurities in the small-molecule fungal inositol acyltransferase 1 inhibitor bulk drug is high in sensitivity and high in specificity, and the blank solvent does not interfere with detection of the impurities.

The invention discloses a cuprous oxide / carbon nitride composite material and a preparation method and application, and belongs to the field of materials.The preparation method comprises the steps that carbon nitride quantum dots are added into a copper salt solution, and walnut-like cuprous oxide / carbon nitride composite particles with cuprous oxide as a main body and carbon nitride monodispersed on the surface of cuprous oxide are obtained through a liquid phase reduction method. The sensing electrode constructed by taking the cuprous oxide / carbon nitride composite material synthesized by the invention as a catalytic medium is high in glucose detection sensitivity and low in detection limit, has excellent performance in the aspect of glucose detection, and also has good photoelectric synergy capability, so that the sensing electrode has better glucose sensing performance. Therefore, the method has huge application potential in the field requiring rapid quantification of glucose.

The invention provides a lactic acid electrochemical sensor LDHamp; the invention relates to construction of BiNPs (at) MWCNTs / GCE and a serum lactic acid detection method, and belongs to the technical field of biosensors, the method comprises the following steps: taking sodium citrate, Bi (NO3) 35H2O and NaBH4 as raw materials, synthesizing BiNPs through a multi-step reaction, compounding the BiNPs with MWCNTs, carrying out carboxyl activation and loading LDH, and finally modifying on a glassy carbon electrode to obtain the sensor. During detection, the sensor is placed in a PBS system containing 5mM of NAD, a serum sample is added, and the concentration of lactic acid is measured by electrochemical scanning according to current response change. According to the method, the detection linear range is 0-200 [mu] M, the detection limit is as low as 0.03 [mu] M, the detection difference of different batches of sensors is small, the method shows the advantages of high sensitivity and good stability, meanwhile, efficient and accurate detection of lactic acid in serum is achieved, and powerful support is provided for clinical diagnosis and disease research.

The invention belongs to the technical field of biosensors, and provides a tetracycline ultra-sensitive detection method based on a CdTe (at) PVP (at) ZIF-8 core-shell material and a cascade amplification sensor. The sensor comprises an Apt-T composite probe, an M-2P chain, a complementary chain C, a self-locking DNAzyme hairpin chain and a hairpin chain H, the Apt-T composite probe is obtained by hybridizing an aptamer Apt and a T chain; the nucleotide sequences of the Apt, the T chain, the template chain M, the enriched chain P, the complementary chain C, the DNAzyme chain and the H chain are as shown in SEQ ID NO: 1-7. The sensor disclosed by the invention has the advantages of broad-spectrum recognition, high specificity, high detection speed, simplicity in operation, low detection limit and the like, can make up for the defects and deficiencies of an existing detection method for tetracycline antibiotics, realizes rapid and accurate ultra-sensitive detection on the tetracycline antibiotics, and has potential application prospects in food safety and environment detection.

The invention discloses a light-activated chemiluminescence immunodetection method for rapidly quantifying C-reactive protein (CRP), and belongs to the technical field of marker detection. Comprising a luminous microsphere-CRP coated antibody complex, a biotin-CRP labeled antibody complex and a streptavidin coated photosensitive microsphere. The light-sensitive microspheres and the light-emitting microspheres are ingeniously combined, and key factors such as coupling efficiency of antibodies on the surfaces of the light-emitting microspheres, reagent dosage, incubation temperature and time and the like are elaborately optimized, so that an optimized light-activated chemiluminescence detection system is constructed. The system not only simplifies the experimental process, but also ensures the reliability and consistency of the detection result by enhancing the stability and specificity of signal transduction. By screening and optimizing conditions of the system, the invention successfully develops a novel CRP (C-reactive protein) light-activated chemiluminescence immunoassay kit, and the detection limit is 6.20 ng.mL <-1 >.

The invention discloses a fluorescent carbon quantum dot, a preparation method thereof and application of the fluorescent carbon quantum dot in atrazine detection, and belongs to the technical field of pesticide residue detection. The carbon quantum dots are obtained by taking citric acid and o-phenylenediamine as raw materials and a mixed solution of ethanol and water as a solvent through the steps of hydrothermal reaction, centrifugation, dialysis, nitrogen blowing, freeze drying and the like. The preparation method provided by the invention has low requirements on equipment, and is simple to operate and low in cost. The fluorescent carbon quantum dots prepared by the method have the characteristics of good fluorescence stability, good water solubility, good selectivity to atrazine, high sensitivity and the like. The detection method shows that the fluorescence enhancement degree of the fluorescent carbon quantum dots and the atrazine concentration are in a linear correlation trend, the detection limit of the detection method is as low as 20ng / L, and the detection result is rapid and accurate. Therefore, the method can be used for rapidly, accurately and sensitively detecting the atrazine in an actual sample and the like.

The invention provides a method for detecting related substances in a tandospirone citrate product, which adopts high performance liquid chromatography and can effectively detect the related substances in the tandospirone citrate product. The detection method provided by the invention has the advantages of no baseline interference, high separation degree, low detection limit, strong specificity, high sensitivity, and good accuracy, precision and durability. According to the invention, new compounds, namely a compound IV, Tand-3, Tand-4, Tand-5, Tand-base-4, Tand-base-6 and Tand-base-8, are also found in the invention. The compound can be used as a reference substance for content analysis and / or quality control of a product containing tandospirone citrate or tandospirone.

The invention relates to an EuW10 / ZIF-8 composite material, a lead ion (Pb < 2 + >) detection and adsorption composite membrane based on the EuW10 / ZIF-8 composite material and a preparation method of the composite membrane, the composite membrane material can rapidly and sensitively detect Pb < 2 + > in a water body and efficiently remove Pb < 2 + > in wastewater, and meanwhile, the composite membrane material has good recycling performance. The EuW10 / ZIF-8 / PVA / PIL composite membrane disclosed by the invention has high-sensitivity detection capability on Pb, effective detection can be realized in a range of 1-106 mu M, and the detection limit is as low as 1 mu M. Other common heavy metal ions have extremely small interference on detection, the selectivity is strong, the concentration of Pb < 2 + > in water can be accurately detected, and a reliable basis is provided for water quality monitoring.

The invention provides an electronic probe quantitative analysis method for trace fluorine elements in an iron-containing sample. According to the quantitative analysis method, during quantitative analysis, the TAPL light splitting crystal is used, the TAPL light splitting crystal has a larger diffraction area, and the obtained count is higher; the interference of the light splitting crystal Fe of the LDE1L is difficult to process; therefore, the TAPL light splitting crystal is used for replacing the LDE1L light splitting crystal and the TAP light splitting crystal; the quantitative analysis conditions are as follows: the acceleration voltage is 15 kV, the beam current is 300 nA, and the beam spot is 20 microns; a TAPL light splitting crystal is adopted, the F content detection limit is 76 ppm (3 sigma), and a TAP light splitting crystal is adopted, the F content detection limit is 195 ppm (3 sigma); when the TAPL spectroscopic crystal is used for testing the trace fluorine element in the iron-containing sample, the detection limit is lower, the detection value is closer to the reference value, and the accuracy is higher.

The invention belongs to the field of analysis and detection, and provides a non-diagnostic method for detecting uric acid in serum based on biochar magnetic nano-enzyme colorimetry. According to the method, the biochar magnetic nano-enzyme is used for activating the potassium hydrogen peroxymonosulfate, then the 3, 3 ', 5, 5'-tetramethylbenzidine is oxidized to generate a blue characteristic product ox-TMB, and the uric acid can inhibit the reaction process, that is, within a certain quantity range, the concentration of the uric acid can be judged according to the change of the absorbance of a reaction system. The nano enzyme is easy to synthesize, low in cost and capable of being stored for a long time, and the uric acid detection method constructed by the invention is low in detection limit (3.85 mu mol / L), wide in linear range (50-1000 mu mol / L), relatively simple, rapid and cheap, and expected to be widely applied to serum uric acid detection.