538 results about "Detection limit" patented technology

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 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 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 provides a wide dynamic range methane detection system based on synchronous accumulation and system reconstruction. The device is characterized by comprising a modulated laser (1), a gas absorption cell (2), a photoelectric detector (APD) (3), a variable gain trans-impedance amplifier (TIA) (4) based on a digital potentiometer, a dual-threshold voltage comparator circuit (5) and a microcontroller processing unit (6). The device can be used for large-dynamic-range real-time monitoring of the methane gas concentration, and the problem that a traditional TDLAS system is prone to saturation or limited in detection limit when the concentration span is large is effectively solved. The method can be widely applied to the fields of gas concentration detection, industrial safety control and the like.

The invention belongs to the technical field of substance detection, and particularly provides application of a chiral Ag / Bi6S2O15NWs composite film with SERS (Surface Enhanced Raman Scattering) activity in detection of ergothioneine. According to the invention, the silver nanowires are assembled into the thin film by using a Langmuir-Blodgett (LB) technology, and a simpler detection method based on SERS (Surface Enhanced Raman Scattering) is developed. The stability and SERS (Surface Enhanced Raman Scattering) performance of the chiral film are further improved by utilizing the coating of the bismuth-based nanowires (Bi6S2O15NWs). The SERS substrate is used for detecting natural L-amino acid EGT with antioxidant and anti-inflammatory effects, and the detection limit of the SERS substrate is 0.248 mu g / mL. The method provides a novel, efficient and sensitive method for detecting EGT in cosmetics, and supports product development and quality control.

The invention belongs to the field of antibiotic analysis and detection, and discloses a quinolone drug SERS (Surface Enhanced Raman Scattering) detection method based on an improved silver nano-substrate and a spectral angle matching model. An improved Lee-Meisel method is adopted to synthesize silver nano sol with precisely controlled particle size, molecular adsorption is realized by utilizing electrostatic interaction of a positively charged quinolone drug and negatively charged silver nano particles, and a high-density Raman enhanced hot spot is formed after an agglomeration agent is added; the SERS spectrum is collected at the excitation wavelength of 785 nm and the integral time of 10 s, qualitative distinguishing of drugs is achieved by combining a spectrum angle matching model, and quantitative detection is achieved by constructing a standard curve through the linear relation between the characteristic peak intensity and the drug concentration logarithm. The detection limit of the four drugs is as low as 1.03-1.16 ppb, the classification accuracy rate reaches 100%, the method is obviously superior to existing similar methods, the detection matrix range is wide, such as animal food and dairy products, and universality and high sensitivity are both considered.

This invention provides a CRISPR / Cas12a fluorescence detection method for FocTR4 based on magnetic bead-ssDNA-HRP probes, belonging to the field of nucleic acid detection technology. This invention involves isothermal amplification of the FocTR4 target sequence using RPA primers; then, a magnetic bead-ssDNA-HRP probe is prepared; and the Cas12a / crRNA complex, RPA amplification product, and probe are co-incubated. The activated Cas12a cleaves the probe, releasing HRP. After magnetic separation, a colorimetric solution containing OPD is added, and the presence and concentration of FocTR4 are determined by detecting the fluorescence signal. This invention combines the high efficiency of CRISPR / Cas12a cleavage with the high sensitivity and strong specificity of RPA technology, achieving highly sensitive and specific detection of FocTR4, with a linear detection range of 10. 2 ~10 7 With a detection limit as low as 70 CFU / mL, it can quickly and accurately detect Foc TR4 in soil samples, enabling rapid on-site detection and providing reliable technical support for the early diagnosis and control of banana wilt disease.

The invention belongs to the field of chemical detection, and particularly relates to a method for detecting ethylene oxide, 2-chloroethanol and acetaldehyde in a frozen beverage by solid-phase microextraction gas chromatography-mass spectrometry. The invention relates to a method for detecting ethylene oxide, 2-chloroethanol and acetaldehyde in a frozen beverage by solid-phase microextraction gas chromatography-mass spectrometry, which comprises the following steps: S.1) taking a frozen beverage sample to be detected, homogenizing and uniformly mixing; s.2) weighing a certain amount of sample, and adding sodium chloride and hydrochloric acid; s.3) determining the sample by adopting a solid-phase microextraction gas chromatography-mass spectrometry method; and S.4) quantitatively analyzing the contents of ethylene oxide, 2-chloroethanol and acetaldehyde in the frozen drink sample to be detected by adopting an external standard method. According to the method disclosed by the invention, the derivatization reaction and the solid-phase microextraction process are combined into one, and the difficulties of complicated pretreatment, long time consumption, low accuracy, unstable result, high detection limit and the like in the traditional analysis technology are overcome. Meanwhile, the precision of a detection result is high, the influence of a complex matrix is removed, and the reproducibility is good.

The invention discloses a method for detecting Escherichia coli in food by combining Fe3O4 (at) Mo-CDs nano-enzyme with an aptamer, according to the method, near-infrared light response molybdenum-doped carbon dot modified Fe3O4 (at) Mo-CDs nano-enzyme is synthesized through a hydrothermal method, the Fe3O4 (at) Mo-CDs nano-enzyme has excellent NIR enhanced peroxidase activity and magnetism, 3, 3 ', 5, 5'-tetramethyl benzidine is oxidized to generate blue oxidized TMB, and the activity and magnetism of the NIR enhanced peroxidase are improved. After the surface of the Fe3O4 (at) Mo-CDs nano-enzyme is functionalized with an escherichia coli nucleic acid aptamer, the POD-like activity of the Fe3O4 (at) Mo-CDs nano-enzyme is inhibited, when Escherichia coli exists, the Fe3O4 (at) Mo-CDs nano-enzyme can be selectively combined with E.coli, the POD-like activity of the nano-enzyme is further inhibited, when the Fe3O4 (at) Mo-CDs nano-enzyme is used for detecting the E.coli in samples such as fruit juice and cakes, the detection limit is as low as 0.767 CFU / mL, and the Fe3O4 (at) Mo-CDs nano-enzyme has relatively high reliability and accuracy and can be widely applied to detection of E.coli. According to the invention, magnetic targeting separation and visual detection of E.coli are realized.

The invention belongs to the technical field of biological detection, and particularly relates to a primer probe pair, a microfluidic chip and a kit for detecting pathogens of vector infectious diseases based on a TaqMan microfluidic chip technology as well as a preparation method and application of the primer probe pair. Based on a TaqMan microfluidic chip technology, the invention provides a detection method for simultaneously detecting 28 kinds of pathogens of the disease-borne infectious diseases, and the related pathogens of the disease-borne infectious diseases comprise viruses, bacteria and parasites, and are wide in range and large in difference. The detection method provided by the invention has a low detection limit (5-20 copies / [mu] L); when the method is applied to an actual sample, the sensitivity, specificity, accuracy and precision are high, and compared with a gold standard method, the consistency is good; and compared with a traditional qPCR method, the method has the advantages that the detection time efficiency and the manpower and material consumption are greatly reduced, and the method is particularly suitable for disease monitoring and emergency disposal scenes with undefined pathogen spectrum, need of rapid and comprehensive troubleshooting and the like, and has a good application prospect.

The application discloses a LAMP primer group, a kit and a detection method for detecting Pinus armandii rust fungus, and belongs to the technical field of genetic engineering. The application takes the specific nucleotide sequence of the large subunit ribosomal RNA of the Pinus armandii rust fungus as a target gene to design and screen a primer group which is specific and high in sensitivity, and can be used for LAMP detection of the Pinus armandii rust fungus. The LAMP primer group provided by the application has the advantages of high universality, high specificity, high sensitivity and good accuracy, and the detection limit can reach 4.5x10 ‑4 ng / μL, which is 100 times higher than the sensitivity of the LAMP detection of different species in the same genus in the prior art, the detection method can rapidly detect the Pinus armandii rust fungus from spore piles and host plant materials, and is suitable for the detection of Pinus armandii seedling materials in forest fields and customs quarantine ports.

The application belongs to the field of pesticide residue detection, and particularly relates to a method for determining pesticides in water samples. The method comprises the following steps: amino modification is performed on MIL-100(Fe) to obtain an amino-functionalized MIL-100(Fe) material; and the pesticides in the water sample are analyzed and detected by using SALDI-TOF-MS with the amino-functionalized MIL-100(Fe) material as a substrate. The application forms a special MOF material by performing amino functionalization modification on MIL-100(Fe), which can enhance the interaction force between the substrate and the analyte, exhibits good ultraviolet absorption and energy transfer capacity, and thus improves the desorption / ionization efficiency in LDI detection. The method is used to detect pesticide residues, and in the low mass region, lower background noise and higher signal intensity are exhibited, so that the detection of pesticide substances in the small molecule region is greatly broken through, and the detection limit is greatly reduced.

The application discloses a method for determining 15 new psychoactive substances in saliva by solid phase supported liquid-liquid extraction (SLE) combined with ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS / MS), which specifically uses a mixed solution of methyl tert-butyl ether and n-hexane as an elution solvent, adopts solid phase supported liquid-liquid extraction to pretreat saliva samples, and then adopts UPLC-MS / MS to detect the collected eluent, so as to realize qualitative and quantitative determination of the new psychoactive substances in saliva. The method has the advantages of rapidness, accuracy, high sensitivity and simple operation, the detection limit of the method is 0.2-0.5 ng / mL, can meet the domestic and foreign limit requirements, and provides technical support for monitoring and investigation of the new psychoactive substances in saliva.

The invention discloses a preparation method of an MF (at) NH2 (at) Ag SERS (Surface Enhanced Raman Scattering) sensor for detecting paraquat and diquat, belongs to the field of nano material synthesis and spectral analysis, and solves the problems that a traditional detection method is complicated in process and cannot detect pesticides and free radicals thereof at the same time, and a traditional SERS substrate is poor in enhancement effect and low in stability. The preparation method comprises the following steps: firstly segmenting melamine foam, cleaning and drying, soaking in hydrochloric acid, soaking in a polyethyleneimine aqueous solution to modify amino, drying, soaking in a silver nitrate solution for ultrasonic treatment, adding a sodium borohydride solution under an ice bath, stirring and reducing, and finally cleaning and drying to obtain the sensor. The sensor takes three-dimensional melamine foam as a support, silver nanoparticles are uniformly loaded on the surface of the three-dimensional melamine foam, paraquat, aquacide and free radicals thereof are enriched through electrostatic interaction based on a localized surface plasma resonance principle, and Raman signal enhancement is realized. The detection limit is 10 <-9 > mol / L, the signal stability and repeatability are excellent, the applicability to actual water sample detection is good, the detection of other pesticides can be expanded, and the method is suitable for on-site rapid trace detection.

The invention discloses an electrochemical aptamer sensor for detecting kanamycin as well as a preparation method and application of the electrochemical aptamer sensor, and belongs to the technical field of electrochemical biosensing analysis. According to the invention, a gold electrode assembled with a kanamycin aptamer with sulfydryl is taken as a sensing interface, a target molecule kanamycin is combined to the sensing interface, and a silver nanoparticle-zirconium-based metal organic framework material signal probe is combined with kanamycin on the sensing interface, so that the sandwich type kanamycin electrochemical aptamer sensor is constructed. The kanamycin electrochemical aptamer sensor prepared by the invention has relatively high sensitivity, relatively low detection limit and relatively wide detection range, the detection limit of the sensor is 0.085 aM, and the detection range is 0.1 aM <-1 > nM. The electrochemical aptamer sensor prepared by the invention is used for quantitative detection of kanamycin, and has the advantages of good stability, strong specificity, good reproducibility and the like.

The invention provides a liquid crystal pollutant underground water detection system based on fluorescence tracing, and relates to the technical field of underground water environment monitoring and pollution prevention and control. According to the system, three types of core structures BAs, CBAs and FBAs of the LCMs serve as targets, a specific fluorescent probe is designed, a water sample is accurately obtained through an underground water in-situ sampling module, and after fluorescence signal amplification and anti-interference processing are conducted, LCMs type recognition and concentration quantification are achieved in combination with a machine learning algorithm. The core innovation lies in the structural adaptive design of the targeted fluorescent probe, the underground water quality anti-interference technology, engineering in-situ detection integration and multi-component synchronous analysis. Practice verification shows that the detection limit of the system to BAs, CBAs and FBAs LCMs is as low as 0.01-0.05 ng / L, the response time is less than or equal to 30 min, the turbidity resistance and ion interference resistance are high, the system is adaptive to engineering scenes such as in-well monitoring and leachate tracing, rapid screening and dynamic tracking of underground water LCMs pollution can be realized, and engineering technical support is provided for underground water pollution prevention, control and restoration.

The application discloses a SERS detection structure for realizing rapid enrichment of detected molecules and a preparation method thereof, and relates to the technical field of molecule detection. The SERS detection structure for realizing rapid enrichment of detected molecules comprises a super-hydrophobic SERS unit and a heating resistor unit which are connected with each other. The heating resistor unit is used for heating the super-hydrophobic SERS unit to realize rapid enrichment of detected molecules. When the detected molecules are dropped on the surface of the super-hydrophobic SERS unit, the SERS detection structure can make the detected molecules be distributed in the form of droplets on the surface of the super-hydrophobic SERS unit. After the solvent is evaporated, the enrichment of the detected molecules can be realized, the detection uniformity is improved, and the detection limit is improved. In combination with the heating effect of the heating resistor unit, the evaporation speed of the droplets can be accelerated, the rapid enrichment of the detected molecules is realized, and the problem of low detection efficiency caused by too long evaporation time of the droplets is avoided. In addition, the detection structure is simple to prepare, does not need to depend on complex preparation steps, and the cost is reduced.

The invention discloses portable AL-AgNPs hydrogel and application thereof in visual detection of carbaryl, and relates to the technical field of food safety detection. Lignin and AgNO3 serve as raw materials, under the action of acrylic acid and ammonium persulfate, AL-AgNPs hydrogel is prepared and mixed with TMB, H2O2 and an HAC-NaAC buffer solution to react, the AL-AgNPs hydrogel is taken out and then soaked in a carbaryl standard solution to be incubated, the AL-AgNPs hydrogel is taken out after incubation, an image of the taken-out AL-AgNPs hydrogel is shot through a mobile phone, RGB analysis is carried out, a B / G value is obtained, and the value of the B / G value is obtained. And establishing a quantitative relationship between B / G and carbaryl concentration, and calculating to obtain the carbaryl concentration in the to-be-detected object. The lowest detection limit of carbaryl detected by the method is 0.1 mu mol / L, which is lower than the maximum residual limit of carbaryl in vegetables in the national food safety standard.

The invention discloses an Aspergillus niger detection kit based on SERS (Surface Enhanced Raman Scattering) and a preparation and detection method thereof, the kit comprises an SERS nano-label, the structure of the SERS nano-label takes bionic gold nanoflower as a gold core, and the surface of the gold core is modified with a Raman reactive dye and an Aspergillus niger specific aptamer. The kit has high sensitivity, specificity, reproducibility, uniformity and stability, Raman spectrum can be collected through portable Raman spectrum equipment, the kit can be used for analysis of trace Aspergillus niger in a sample, and the detection limit is lower than 10 CFU / mL. Compared with a traditional bacterial culture method, the method has the advantages in the aspects of simplicity and convenience in operation, detection period, analysis cost and the like. The method is suitable for food safety monitoring.

The embodiment of the present disclosure provides a concentration analysis method for ultra-low concentration of acidic gas in background atmosphere, which is applied to the technical field of atmospheric environment monitoring and meteorological observation. The method comprises the following steps: selecting at least two suitable blank filter membranes according to the chemical properties of the target acidic gas; arranging the blank filter membranes in the sampling device of the atmospheric background station in a preset serial order for continuous sampling; performing extraction treatment on the sampled filter membranes respectively, and using an ion chromatograph to quantitatively detect the target ion concentration in the extraction liquid, and converting the mass of the corresponding acidic gas; based on the flow monitoring data during sampling, calculating the total sampling volume through a conversion equation, and combining the mass of the acidic gas to calculate the concentration value of the target acidic gas. In this way, the problems of low enrichment efficiency, high detection limit and invalidation of online instruments due to concentration lower than the detection limit of the traditional method can be solved, and accurate capture and quantification of ultra-low concentration of acidic gas in background atmosphere are realized.

The invention relates to a method capable of monitoring physiological phosphate, in particular to a colorimetric sensor array based on MIL-101 (Fe) and a preparation method and application of the colorimetric sensor array. Nitro and amino are attached to MIL-101 (Fe), and a sensor array is constructed based on the three kinds of Fe-MOFs. Sensing image information of phosphate before and after a reaction in a colorimetric sensor array is obtained, RGB difference values of all colorimetric points before and after the reaction are obtained to obtain an LDA image, the lowest detection limit can be as low as 0.1 mu M. The array not only has good discrimination capability on ten phosphate compounds such as ATP, ADP, AMP, adnosine, Pi, PPi, UTP, GTP, ITP and CTP, but also has good detection effect on phosphate compounds such as phosphate compounds. And under the condition that interferents (ions, amino acids and the like) are contained, accurate identification can be realized. The colorimetric sensor array can also distinguish different PPs in fetal calf serum. The metal-organic framework sensor array has a good prospect as a novel college sensing platform of phosphate and other disease-related biomolecules.

The invention relates to the technical field of drug detection, in particular to a molecularly imprinted sensor for quantitatively detecting olanzapine in human blood as well as a preparation method and application of the molecularly imprinted sensor. Au-Pt NSF is deposited on the surface of a substrate electrode through an HBDT method, then a molecularly imprinted polyaniline layer is prepared through electro-polymerization, and the molecularly imprinted sensor is formed. A classical redox probe potassium hexacyanoferrate is used as a tool, and DPV is used for monitoring current change (delta I) caused by olanzapine addition, so that sensitive quantitative detection of olanzapine is realized. The sensor prepared by the invention shows a good linear relationship to olanzapine in the concentration ranges of 0.005-0.4 mu M and 0.4-10 mu M, the detection limit is 0.94 nM, and the sensor has high reproducibility and stability (relative standard deviation RSDlt;

The invention discloses a near-zero background fluorescence sensor based on polydopamine functionalized MXene as well as a preparation method and application of the near-zero background fluorescence sensor, and belongs to the technical field of universal biosensing. The sensor comprises a polydopamine functionalized MXene material and a quantum dot-aptamer fluorescent probe which is accurately coupled by click chemistry in a ratio of 1: 1. The detection method is characterized in that a target object is utilized to induce the probe to desorb from the surface of a material, and a supernatant containing the free probe is physically separated from a material precipitate through centrifugal separation, so that background fluorescence interference is almost completely eliminated. According to the invention, ultra-sensitive detection of aflatoxin B1 is realized, and the detection limit of AFB1 in complex matrixes such as corn flour is as low as 0.27 mu g / kg. All components of the platform can be modularly and independently stored for a long time, the platform can be directly applied to detection of various micromolecular mycotoxins without optimization by replacing aptamers, and the platform has high sensitivity, high stability and high universality.

The application discloses a method for detecting polychlorinated biphenyl by using an electrochemical aptamer sensor. x The sensor comprises a glassy carbon electrode, a surface of a detection end of the glassy carbon electrode is decorated with an electroactive nanomaterial, the electroactive nanomaterial comprises Ti3C2T 0000001 Nanosheet, a conductive polymer material is embedded in an interlayer structure of the nanosheet and forms a composite nanomaterial, and gold nanoparticles are deposited on a surface of the composite nanomaterial; a capture chain is self-assembled on the electroactive nanomaterial, a specific aptamer probe is combined on the capture chain, a DNA double-stranded structure is formed, and an electroactive label is introduced. In the application, the sensor has the advantages of wide detection range, low detection limit, strong anti-interference ability, good stability and the like, can realize specific detection of polychlorinated biphenyl, has the advantages of low cost, short time consumption, high accuracy, good adaptability and the like, and has important significance for rapid detection of polychlorinated biphenyl.

The invention discloses an LAMP (Loop-Mediated Isothermal Amplification) detection primer combination and a kit for a peach brown rot pathogen dominant species Monilinia fraucticola and application of the LAMP detection primer combination and the kit. The primer combination comprises a forward outer primer F3, a reverse outer primer B3, a forward inner primer FIP and a reverse inner primer BIP, and nucleotide sequences of the forward outer primer F3, the reverse outer primer B3, the forward inner primer FIP and the reverse inner primer BIP are sequentially shown as SEQ ID NO.1-SEQ ID NO.4. The invention further discloses a kit for detecting the peach brown rot pathogen dominant species Monilinia fraucticola. According to the LAMP detection primer combination designed by aiming at the dominant species Monilinia fraticola, four specific primer combinations are designed by aiming at the specific gene BI-1 sequence of the Monilinia fraticola, the characteristic nucleic acid fragment of the Monilinia fraticola can be accurately identified in the detection environment such as the field, and the condition of cross reaction or misjudgment does not occur after repeated verification for multiple times. Meanwhile, due to the adaptability of the primer combination and the LAMP amplification technology, the detection limit concentration is as low as 1 * 10 <-2 > ng / mu L, stable detection can be realized even under the conditions of early infection of pathogenic bacteria and extremely low content of thalli in field samples, and a reliable technical basis is provided for early warning and source control of peach brown rot.

The invention discloses a method for determining L-azetidine-2-carboxylic acid, and provides a method for detecting AZE in food, living body and environment by adopting a liquid chromatography-tandem mass spectrometry and selecting a positive and negative ion switching scanning mode. The method can be used for screening the content of AZE in food and guiding the diet of C9-ALS patients. The method is high in detection sensitivity, the detection limit of AZE is 2.0 ng / L, the accuracy is high, and the method is superior to an existing detection technology.

The invention discloses a detection method of inflammatory marker protein. According to the method, the micro-fluidic chip with a sample loading area, a buffer treatment area, a sample channel and a detection area is prepared on filter paper through wax printing; chitosan is preset in the sample loading area and is used for treating a sample, and bromothymol blue is fixed in the detection area and is used as a pH indicator. During detection, a sample is driven by a phosphate buffer solution with the pH value of 6.0 to flow to a detection area through capillary action, the C-reactive protein and the indicator are subjected to non-specific binding, so that the color of the detection area is changed from yellow to green, the length of a green developing signal is in direct proportion to the concentration of the CRP, and quantitative detection can be realized by measuring the length. The method does not need an antibody, is low in cost, is simple and convenient to operate, can complete detection within 15 minutes, has the detection limit of 1.56 ng / ml and the linear range of 5-25 ng / ml, and is suitable for rapid screening and field detection of basic medical institutions.

The invention discloses Cu / CuO / Ag nano-particles and a preparation method and application thereof, and the method successfully prepares the Cu / CuO / Ag nano-particles with regular morphology and uniform dispersion by optimizing a dual-stabilizer system and a step-by-step reduction-replacement process. The material has dual functions of SERS enhancement and catalysis: as an SERS substrate, the enhancement factor of rhodamine 6G reaches 5.3 * 10 < 8 >, the detection limit is as low as 5.0 * 10 <-13 > mol / L, and the reproducibility is good (RSD = 6.2%); meanwhile, as a catalyst for hydrazinolysis and reduction reaction, by optimizing a reaction solvent and the pH value of a system, the reaction efficiency is remarkably improved, and an additional incubation step is not needed. The detection limit on the plasticizer DOTP can reach 2.0 * 10 <-9 > mol / L, and the method has the advantages of simplicity and convenience in operation, good reproducibility, high analysis speed and the like, and is suitable for rapid screening and quantitative analysis of plasticizers in food packaging, environmental water bodies and medical instruments.

The invention relates to a method based on Mnamp; the invention discloses a carbaryl three-mode detection method and a photocatalytic degradation method of TiO2 (at) C3N4NPs, and belongs to the technical field of environment and food pollution detection and treatment. The invention discloses a preparation method of Mnamp with peroxidase-like activity and photocatalytic activity. According to the preparation method of the TiO2-coated C3N4 fluorescent nano-enzyme, the TiO2-coated C3N4 fluorescent nano-enzyme has the capabilities of detecting and degrading pesticides in multiple modes. A colorimetric-photo-thermal-fluorescence three-mode combined strategy is adopted, the detection accuracy is high, and matrix interference is resisted; the detection sensitivity is high, the detection limit of a colorimetric mode reaches 0.047 [mu] mol / L, the detection limit of a photo-thermal mode reaches 0.159 [mu] mol / L, and the detection limit of a fluorescence mode reaches 0.185 [mu] mol / L; on-site and real-time rapid semi-quantitative and even quantitative analysis can be realized; mn < amp >; after the detection of the TiO2 (at) C3N4NPs is completed, the TiO2 (at) C3N4NPs can also be used for carrying out photocatalytic degradation on carbaryl.

The invention discloses an SERS (Surface Enhanced Raman Scattering) flexible sensor based on dual-ion modification as well as a preparation method and application of the SERS flexible sensor, and belongs to the technical field of biomedical detection. A bacterial cellulose membrane (BCM) is used as a base material, cation modification (QBCM) is carried out through glycidyl trimethyl ammonium chloride (EPTMAC), anion modification (TABCM) is carried out through tannic acid (TA), a functional substrate with asymmetric charge distribution and a porous structure is constructed, then Ag NPs are loaded on the modified base material through an in-situ reduction method, the QBCM-coated AgNPs and TABCM-coated AgNPs dual-ion active substrate is formed, and the AgNPs / TABCM-coated AgNPs dual-ion active substrate is used for preparing the composite material. The SERS flexible sensor is integrated through a layer-by-layer self-assembly (LbL) technology; the SERS flexible sensor can realize specific enrichment and synchronous detection of anionic kynurenic acid (KYNA) and cationic spermine (Spm) in urine, and is low in detection limit and good in reproducibility.