238 results about "Nanoprobe" patented technology

The invention discloses a reversible background-free hydrogel nanosensor for acetone detection and an intelligent sensing platform, and relates to the technical field of biosensors. The hydrogel nanosensor consists of a hydrogel matrix and an upconversion nanoprobe, and the upconversion nanoprobe comprises upconversion nanoparticles (UCNPs), hydroxylamine sulfate and thymol blue (TB). The invention adopts hydroxylamine sulfate as a specific recognition unit of acetone to construct a reversible luminescent hydrogel probe for acetone detection, and the probe can be reused in multiple detections, thereby reducing the cost of a single detection. In addition, by adopting near-infrared light as an excitation light source, the autofluorescence interference of the hydrogel matrix is ​​effectively avoided, thereby improving the detection accuracy.

The invention discloses an acid responsive nanoprobe as well as preparation and anti-tumor application thereof. The nanoprobe has a core-shell structure, takes a nanoparticle self-assembled by a polycation aggregation-induced emission (AIE) photosensitizer and functional nucleic acid as a core, and takes a hyaluronic acid modified metal polyphenol network as a shell. The nanoprobe utilizes the acid responsiveness and broad-spectrum absorption performance of the metal polyphenol network and the diagnosis and treatment advantages of the polycation AIE photosensitizer to realize the acid responsiveness'switch 'controllable diagnosis and treatment of the tumor nanoprobe. In a neutral environment, the fluorescence is weak, the generation of ROS is less, and the background noise signal of the nanoprobe and the toxicity of non-targeted tissues are reduced; in an acid environment, fluorescence is enhanced, the ROS yield is improved, and the treatment efficiency and the curative effect monitoring accuracy are improved. The nano diagnosis and treatment probe is ingenious in design and simple to prepare, and can realize PDT and gene therapy synergistic anti-tumor, in-situ real-time report of early tumor treatment effect and assistance in precise cancer treatment.

The invention discloses a silicon shell protected magnetic quantum dot nanoprobe, a preparation method, a kit and application. The nanoprobe comprises a nanomaterial and a specific antibody, the nanometer material is of a core-shell structure, and the outer surface of a core is sequentially coated with an interlayer and a protective shell layer outwards. The interlayer comprises a multi-layer laminated structure formed by alternately arranging a plurality of layers of positive electricity interlayers and negative electricity interlayers; the positive electric interlayer is polyethyleneimine, the negative electric interlayer is quantum dots, the quantum dots are CdSe / ZnS or carbon quantum dots, amino groups on the surface of the shell layer and a dialkynyl polyethylene ethanol solution are subjected to general coupling of specific antibodies in a click chemistry mode by taking diyne molecules as connecting arms. The magnetic nanoprobe with the core-shell structure not only has strong magnetic responsiveness and a high fluorescence signal, but also can adapt to a complex environment, after the magnetic nanoprobe is integrated with an immunochromatography test strip, to-be-detected targets including pathogenic bacteria and inflammatory markers can be rapidly captured in a whole blood sample at the same time, and the magnetic nanoprobe has huge application potential in early diagnosis of sepsis.

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 relates to the technical field of terahertz biosensing, in particular to a terahertz biosensing detection device and a biological detection method. The system is used for detecting a biological sample and comprises a transmission-type terahertz time-domain spectroscopy system for providing a transmission-type terahertz light path; the metasurface sensor is located on a transmission-type terahertz light path, the metasurface sensor comprises a plurality of first gold films and second gold films of asymmetric structures in a periodic array, and under normal incidence of terahertz waves in the polarization direction, a transmission spectrum harmonic peak is excited to characterize a biological sample; the captured DNA is modified on the surface of the super-surface sensor and is used for capturing a biological sample; the gold nanoprobe is used for being specifically combined with a biological sample after capturing the biological sample so as to enhance the sensing sensitivity to the biological sample. According to the invention, the metasurface sensor and the gold nanoprobe are combined for detection, so that high-sensitivity detection of trace micromolecular biological samples can be realized.

The invention provides an activatable head and neck cancer diagnosis and treatment integrated nanoprobe and a preparation method and application thereof.The preparation method includes the steps that according to an original data matrix, an adaptive spectrum correction algorithm is applied to eliminate background noise of an instrument, and when the relative fluctuation of spectral intensity exceeds a preset threshold value by 5%, a sliding window filtering technology is adopted, the window size is 5 nanometers, and the spectrum intensity is obtained; generating a de-noised spectral data set; measuring the pH value of the head and neck cancer tissue microenvironment by using a pH value sensor, recording the emission peak position change of the near-infrared quantum dots when the pH value is less than 6.5 in combination with the de-noising spectral data set, analyzing the frequency band displacement by adopting a Gaussian fitting algorithm, and generating a mapping data set of the pH value and the frequency band displacement; and aiming at the activation spectrum fingerprint data set, applying a dynamic spectrum matching algorithm, comparing with the spectrum response characteristic data set, calculating a cosine similarity coefficient, and when the similarity exceeds 0.85, determining the activation state and the tissue penetration depth of the nanoprobe, and generating a diagnosis and treatment parameter adjustment instruction set.

The invention discloses a method and device for measuring structural parameters of an MEMS cantilever beam, and the method comprises the steps: placing the MEMS cantilever beam on an objective table of a nanoprobe station, and guaranteeing that the thickness direction of the MEMS cantilever beam is perpendicular to a horizontal plane; measuring the length l and the width b of the MEMS cantilever beam by using a microscope; controlling a micro probe of the nano probe station to descend until the micro probe is in contact with the surface of the MEMS cantilever beam; continuously controlling the micro-probe to descend, and recording the displacement X and the loading stress F of the micro-probe at the same time; carrying out linear fitting by utilizing a preset calculation device displacement X and the loading stress F to obtain the deformation rigidity K of the MEMS cantilever beam; and calculating the thickness h of the MEMS cantilever beam based on the deformation stiffness K, the length l, the width b and the Young modulus E. The measuring method is wide in application range and low in testing cost.

The invention discloses a gold-silver alloy nanoprobe based on double-signal cooperative detection, a preparation method and application thereof, and belongs to the technical field of sensing. Then mixing the gold nanorod, a Raman report molecule p-methylthiobenzonitrile and a chiral stimulating factor L-cysteine, and jointly incubating at room temperature to obtain a mixed solution; sequentially adding silver nitrate, chloroauric acid tetrahydrate and ascorbic acid into the mixed solution, and magnetically stirring; and placing the mixed solution under a constant temperature condition to react for a certain time, so that the gold-silver alloy shell fully grows, and finally obtaining the spiral structure alloy nanoprobe with Raman signals and CD signals. The probe realizes the dual detection functions of Raman signals and circular dichroism signals, and can detect the lactic acid concentration with high sensitivity and high selectivity by combining the specific catalytic action of the lactate oxidase, and meanwhile, the Raman signals and CD signals of the silent zone can further expand the application range of the probe.

The invention discloses a method for detecting silicon dioxide in kaolin based on a nanoprobe. The method comprises the following steps: grinding a kaolin sample, mixing with deionized water, performing ultrasonic dispersion, and centrifuging to obtain a kaolin sample solution; the preparation method comprises the following steps: preparing titanium dioxide nano-particles with amino groups modified on the surfaces by adopting a hydrothermal method, and modifying a silane coupling agent on the surfaces of the nano-particles by adopting a chemical coupling method to form a functionalized nano-probe; adding the functionalized nanoprobe into a kaolin sample solution; the nanoprobe is combined with silicon dioxide in a sample to form a nanoprobe-silicon dioxide compound; collecting a nano probe-silicon dioxide compound; reacting the nanoprobe-silicon dioxide compound with a fluorescent marker, and combining the fluorescent marker with silicon dioxide in the compound; and detecting the fluorescence intensity, and calculating the content of silicon dioxide in the sample according to the standard curve. The method for detecting silicon dioxide in kaolin is high in sensitivity, high in selectivity, simple and convenient to operate and wide in application.

The present invention provides a glutathione-activated co-assembled nanoprobe and a preparation method and application thereof, belonging to the technical fields of chemical synthesis, biological analysis and detection, tumor imaging and treatment. In the present invention, amphiphilic small molecule probes 1-Zn-PPA and 1-NLG are constructed, and the probes 1-Zn-PPA and 1-NLG can be co-assembled in a solution to form co-assembled nanoprobes 1-NPs. The nanoprobes 1-NPs can accumulate at the tumor site under the tumor EPR effect and the targeting action of cRGD on the probe surface, and disassemble under the action of GSH present in the tumor reducing environment to release Gd-containing hydrophilic small molecule 2-Gd, light / sound-sensitive drug Zn-PPA-SH and immune adjuvant drug NLG919. The nanoprobes 1-NPs can realize combined sonodynamic therapy / photodynamic therapy / immunotherapy of living tumors. The nanoprobes 1-NPs have good applications in fluorescence imaging, magnetic resonance imaging, and the preparation of tumor treatment drugs and tumor-killing devices.

The invention discloses a near-infrared two-region dual-channel fluorescent nanoprobe as well as a preparation method and application thereof, and relates to the technical field of biomedical imaging. A nano probe A and a nano probe B included in the near-infrared two-region dual-channel fluorescent nano probe are both of a core-shell structure, two NIR-IIb fluorescent nano probes adaptive to different excitation wavelengths (808 nm and 980 nm) are constructed by precisely regulating and controlling the types and proportions of lanthanide elements, dual-channel imaging is achieved, limitation of a single excitation wavelength is broken through, spectral crosstalk is eliminated, and the near-infrared two-region dual-channel fluorescent nano probe has the advantages of high sensitivity, high sensitivity, high sensitivity and the like. The method has the characteristics of material uniformity and biological safety. The near-infrared IIb region dual-channel imaging system has the characteristics of high temporal-spatial resolution and signal separation, and has significant application value in the field of living body multi-target synchronous observation. Compared with a traditional two-photon microscope technology, the imaging method has a wider observation view field, a local craniotomy operation does not need to be carried out on an experimental mouse, and physiological trauma is remarkably reduced.

The application belongs to the technical field of luminescent materials, and particularly relates to a nickel ion doped fluoride near-infrared two-region long-wave luminescent nano probe and a preparation method thereof, wherein the nano probe comprises a fluoride nanocrystal matrix and transition metal nickel ions as a luminescent center, or a core-shell structure nano probe formed by taking the above-mentioned substances as a shell layer and being externally coated with an inert shell layer or a homogenous epitaxial layer. The probe realizes wide-range regulation of an emission peak in a 1300nm to 2150nm near-infrared two-region long-wave band; through core-shell structure design and inert shell layer coating, surface defects are effectively passivated, luminescent quantum efficiency is significantly improved, and particle size is precisely controlled. Through nickel ion doping and crystal field regulation strategies, the application develops a new type of non-lanthanide near-infrared two-region long-wave luminescent material; the application has unique dual-wavelength excitation characteristics and wideband emission characteristics, and has wide application prospects in multi-channel biological detection and imaging analysis.

The present invention discloses a large-dynamic scattering terahertz material imaging and composition analysis device and method. The device includes a dual-port frequency-sweep excitation signal generation and intermediate frequency signal detection module, a two-way low-noise amplification and mixing module, a low-noise amplification module, an IQ mixing amplification module, a data acquisition module, and an industrial control computer, all of which are sequentially connected. The dual-port frequency-sweep excitation signal generation and intermediate frequency signal detection module are respectively connected to a terahertz signal frequency-doubling transmission module and a terahertz signal frequency-mixing detection module via a switch matrix. A signal transmission adjustment device, a nanoprobe, a piezoelectric body, a two-port excitation source, and a three-dimensional scanning frame for moving the sample to be tested are provided between the terahertz signal frequency-doubling transmission module and the terahertz signal frequency-mixing detection module. The device and method of the present invention can break through the diffraction limit and achieve nanoscale imaging; possess near-field terahertz scattering spectrum analysis capabilities, realize material composition analysis, and achieve large-dynamic testing with an accuracy exceeding 100dB across the entire frequency band.

The invention relates to an application of a nanosphere fluorescent probe combined CRISPR (clustered regularly interspaced short palindromic repeats) in detection of exosomes, which comprises the following steps: inserting DNA nanospheres as a carrier of fluorescent signal molecule methylene blue into a cholesterol probe on an exosome membrane to start a strand displacement reaction, activating trans-cleavage activity of Cas12a by a reaction product to split the DNA nanospheres wrapped with methylene blue, further, qualitative and quantitative analysis of the exosome is realized through fluorescence signal detection of methylene blue. Compared with a common CRISPR / Cas-based biosensing platform, the nanosphere fluorescent probe and the CRISPR are combined, so that high-sensitivity detection of the exosome can be realized, and the application scene of the nucleic acid nanoprobe and the CRISPR-Cas system in fluorescent biosensing is widened.

The present application relates to the technical field of nanoprobes, and particularly relates to a near-infrared fluorescence / magnetic resonance dual-mode probe and a preparation method and application thereof. The present application adopts a Brij98 amphiphilic molecule to wrap an IR824Et-PhDTA-Gd near-infrared fluorescence / magnetic resonance dual-response molecule to prepare the probe, so that the probe has an absorption wavelength of 650-850 nm, generates a fluorescence signal under excitation of 785 nm laser, and the generated fluorescence wavelength can reach 1000 nm, which is in a near-infrared region (780-1700 nm); the probe has good positive magnetic resonance response characteristics, and a longitudinal relaxation rate (r1) of the probe is 28 mM ‑1 s ‑1 , which is 7 times of that of a clinically used Magnevist; the probe can be applied in the fields of fluorescence and / or magnetic resonance imaging, and has a wide application prospect. The preparation method of the near-infrared fluorescence / magnetic resonance dual-mode probe is simple in operation and low in cost.

The invention discloses NaYF4: Yb, Er (at) NaYF4 (at) SiO2 (at) AgNPs as well as a preparation method and application thereof in vitamin B12 detection. According to the method, a core NaYF4: Yb, Er and a core shell NaYF4: Yb, Er (at) NaYF4 are prepared through a high-temperature solvothermal reaction; and carrying out hydrophilic modification and fluorescence enhancement modification to obtain the nano probe. Compared with the prior art, the invention has the following advantages: (1) the NaYF4: Yb, Er (at) NaYF4 (at) SiO2 (at) Ag NPs can absorb exciting light at 980nm and convert the exciting light into visible fluorescence, and through an energy transfer mode, an up-conversion fluorescence emission peak and an ultraviolet absorption peak of vitamin B12 coincide, so that rapid detection is realized; (2) the nanoparticles and the application method have the advantages of high sensitivity, convenience and rapidness in operation, good specificity and the like.

The invention relates to the technical field of magnetic particle imaging, in particular to a core-shell nanoprobe and a preparation method and application thereof.The core-shell nanoprobe comprises a magnetic core and a nanoshell which is located outside the magnetic core and has a magnetic shielding response function, and the structure of the nanoshell collapses under the tumor microenvironment condition; the saturation magnetization of the magnetic core is greater than or equal to 50 emu / g, and the coercive force is less than or equal to 5 Oe; the saturation magnetization of the nano shell is less than 50 emu / g, and the coercive force is more than 5 Oe. According to the core-shell nanoprobe, through a unique magnetic core-shell structure design and tumor microenvironment response characteristics, a magnetic shielding layer is formed by using a low-signal nano shell with a response magnetic shielding function, and background signal interference is inhibited. In a tumor microenvironment, the shell structure of the core-shell nanoprobe collapses, the magnetic core is exposed, and a high magnetic signal is released and generated, so that the imaging signal-to-noise ratio is remarkably improved. According to the invention, the bottleneck that the traditional MPI probe is lighted in the whole course can be broken through, the tumor specificity is lighted and positioned, and the problems that the external background of the tumor is high, the contrast ratio is poor, and tiny focuses are difficult to detect are solved.

The invention discloses an MMP-9-targeted MRI (Magnetic Resonance Imaging) nanoprobe and a preparation method and application thereof, the MMP-9-targeted MRI nanoprobe is represented by Gd-ACC-MAP and comprises amorphous calcium carbonate and an aptamer covalently connected to the surface of the amorphous calcium carbonate, the calcium carbonate is doped with gadolinium, and the aptamer has a nucleotide sequence as shown in SEQ ID NO: 1. The MRI nanoprobe can be used for early diagnosis of aneurysm and evaluation of rupture risk of the aneurysm.

The invention relates to the technical field of biology, and discloses a nano composite probe as well as a preparation method and application thereof. The nano composite probe comprises an iron-based metal organic framework, glucose oxidase loaded on the surface of the iron-based metal organic framework, and an anti-cTnI antibody coupled with the glucose oxidase. According to the nano-composite probe, glucose oxidase, an acid-responsive iron-based metal organic framework and a detection antibody are subjected to function integration, so that three-in-one of recognition, driving and feedback is realized; a cardiac troponin I detection method based on a nanoprobe triggered enzyme catalysis-MOF disintegration-Fenton reaction self-amplification cascade system innovatively adopts a strategy of etching a DNA protective layer by hydroxyl radicals to regulate and control gold nanoparticle salt-induced aggregation, and finally reads signals through dynamic light scattering, so that ultrahigh-sensitivity detection is realized, the detection limit is as low as 1.5 * 10 <-13 > g / mL, and the detection time is greatly shortened. The stability and the specificity are excellent.

The present invention relates to a metaallylsilane-based linker compound, a method for preparing same, and the like. The present invention makes it possible to prepare a nanoprobe in which two or more functional molecules are incorporated in a silica nanoparticle that is modified with the linker compound by means of a one-pot process through a continuous bioorthogonal reaction. The nanoprobe of the present invention can be incorporated in a targeting ligand capable of delivering a drug to a specific location, a fluorescent dye for molecular imaging, a radioactive isotope, a magnetic substance, a drug for treatment, and the like, and thus can be used for in vivo molecular imaging, theranostics, and the like.

The application discloses a kind of near-infrared afterglow nano probe and its preparation method and application, wherein the near-infrared long afterglow nano probe is near-infrared long afterglow nano probe, particle size is 100nm, and its composition is: ZnGaSnO4:Cr, Y, wherein, the ratio of Zn, Ga, Sn, Cr, Y is 1.3:1.4:0.3:0.005:0.003, the near-infrared long afterglow nano probe of the application has higher luminous intensity and excellent fluorescent performance, is a new type of luminescent material, can emit light for more than several hours under external environment, has high luminous intensity, long life and good chemical stability and other characteristics, has the advantages of low background, strong fluorescent signal, high signal-to-noise ratio and the like, label is connected with oxidized low density lipoprotein monoclonal antibody by covalent bond, and the labeled product is stable, has the characteristics of high sensitivity, high accuracy, rapid and simple detection and the like, early diagnosis, curative effect monitoring and prognosis evaluation of coronary heart disease and atherosclerosis can quickly help clinical diagnosis.

The application discloses a kind of near-infrared benzothiadiazole dye sensitized rare earth upconversion luminescence nano-probes and preparation method thereof;Probe is composed of near-infrared benzothiadiazole dye and upconversion nanoparticle, benzothiadiazole dye is compounded with ligand-free lanthanide ion doped upconversion nanoparticle, and upconversion luminescence is enhanced.This application preparation method is simple, and it does not involve complex core-shell structure and energy migration process, benzothiadiazole dye is directly compounded with ligand-free rare earth nanoparticle, and upconversion luminescence nano-probe is formed, under the irradiation of 808nm laser, the emission spectrum of benzothiadiazole dye and the absorption spectrum of sensitizer ion in upconversion nanoparticle overlap, which can effectively enhance the upconversion luminescence intensity of nano-probe, and keep good light stability, keep more than 90% of initial luminescence intensity under the irradiation of 120 minutes excitation light.

The invention discloses a near-field terahertz nonlinear optical effect excitation detection method and system. A femtosecond laser space-time shaping technology is combined, a strong terahertz pulse is generated based on a femtosecond laser filament, the strong terahertz pulse is coupled with a tapping mode atomic force microscope, and space-time matching of probe vibration and the terahertz pulse is accurately controlled by using a synchronous sampling method, so that the time-space matching of the probe vibration and the terahertz pulse is realized. Mismatch between the low-repetition-frequency strong-field terahertz pulse and the vibration frequency of the near-field microscope probe is overcome, and strong-field terahertz near-field coupling and detection are achieved. The local field enhancement effect of the tip of the nanoprobe can realize nanoscale focusing (peak field intensity reaches MV / cm magnitude) of a terahertz field at a probe-sample gap, the near-field nonlinear interaction is remarkably enhanced, the diffraction limit is broken through, and the nanoscale spatial resolution is realized. According to the method, the excitation detection efficiency and the spatial resolution of the terahertz nonlinear effect are remarkably improved, and accurate excitation, characterization and regulation of the nonlinear optical effect of the sample can be realized.

The present invention provides a universal fluorescent probing system and method for result readout of loop-mediated isothermal amplification (LAMP) or reverse transcription-loop-mediated isothermal amplification (RT-LAMP) in a closed-tube manner using at least three different types of universal quantum dot probes, including sulfonate-, carboxyl-, and amine-modified quantum dots (QDs). Detection mechanism of the present system and method relies on a co-precipitation of the modified QDs with magnesium pyrophosphate crystals (one of the positive LAMP / RT-LAMP reaction products) formed during the reaction. The present system and method are advantageous over the existing technologies in terms of simple preparation, low cost, as well as excellent universality, specificity and sensitivity.

The invention provides a method for quantitatively detecting a low-abundance protein biomarker by combining a photosensitive nanoprobe with Cas12a, which comprises the following steps: identifying and enriching a target to be detected in serum through the photosensitive nanoprobe DA / PL-coated Cu NPs, and converting a signal of the target to be detected into a plurality of PL signals through photolysis to generate first signal amplification; the released PL is specifically recognized through Cas12a, the Cas12a is activated after being combined with the PL and does not specifically cut a signal label containing a fluorescence quenching group, a fluorescence signal is released, secondary signal amplification is generated, and quantitative detection of a to-be-detected target in serum is achieved by detecting the fluorescence signal. According to the method disclosed by the invention, ultra-sensitive dual signal amplification is realized through combination of the photosensitive nanoprobe and Cas12a, and the method has the advantages of high reliability, high sensitivity and high specificity and can be used for rapidly and accurately detecting low-abundance protein biomarkers in serum.

The application relates to the technical field of long-afterglow materials, and particularly provides a preparation method of a near-infrared long-afterglow luminescent nano probe and application thereof. The preparation method of the near-infrared long-afterglow luminescent nano probe comprises the following steps: dissolving water-soluble zinc salt, water-soluble tin salt, water-soluble gallium salt, water-soluble chromium salt and water-soluble yttrium salt in water to prepare a metal mixed solution with a salt concentration of 0.1-2 mol / L; adding mesoporous silica powder into the metal mixed solution, uniformly dispersing, stirring for 30 min-48 hours, adding an alkaline precipitant drop by drop until the pH is 8-10, collecting the precipitate, drying, high-temperature calcining, and obtaining doped particles; and coating manganese dioxide on the surface of the doped particles, and the near-infrared long-afterglow luminescent nano probe has the characteristics of slow afterglow decay.

The invention discloses a Candida albicans specificity detection kit and application thereof, the kit comprises a nanoprobe, the nanoprobe takes a gold nanostar as a substrate, and the surface of the substrate is modified with Raman probe molecules and a Candida albicans specificity 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 analyzing trace Candida albicans in a sample, and the detection limit is 1.14-1.21 CFU / mL. Compared with the traditional method, the detection method of the kit has the advantages of simple pretreatment process, short detection time, simplicity in operation and the like, obviously reduces the time and economic cost, and is more suitable for on-site rapid detection of candida albicans.

The invention belongs to the technical field of fluorescence detection, and particularly relates to a method for detecting trace water in an organic solvent. In the invention, the sodium erbium tetrafluoride serving as the probe can emit light under the irradiation of exciting light, and the detection of trace water in an organic solvent can be realized through the change of the intensity ratio of two specific light-emitting peaks along with the water content by utilizing the difference of the multi-phonon relaxation probability influence degrees of water molecules on the light-emitting energy levels of all excited states of erbium ions. The trace water detection nanoprobe adopted by the invention is non-toxic, stable in photochemical property, strong in anti-interference capability, easy to store, high in detection sensitivity and simple to operate, and is expected to be used in the fields of industrial production, drug synthesis, food processing, environmental monitoring and the like.

The invention discloses a bimetal SERS (Surface Enhanced Raman Scattering) nano probe based on a biological silence region as well as a preparation method and application of the bimetal SERS nano probe. According to the sensor, AuNS (at) 4-MBN (at) Ag-aptamer is adopted as the nano probe, and Fe3O4 (at) AuNPs-cDNA (FA-cDNA) is adopted as a magnetic substrate. In the sensor, an FA-cDNA (complementary deoxyribonucleic acid) and AuNS (at) 4-MBN (at) Ag-aptamer form an FA-cDNA-aptamer-AuNS (at) 4-MBN (at) Ag magnetic complex through a base complementary pairing effect. The SERS sensor established by the bimetal nanoprobe in the'biological silence 'region has important practical application significance in trace CPF detection in a complex matrix environment.

The invention relates to a magnetic quantum dot composite nanoprobe as well as a preparation method and application thereof. The composite nanoprobe comprises a composite nanomaterial and a specific antibody, the composite nano material has a core-shell structure; the core of the core-shell structure is Fe3O4 nano-particles, and the outer surface of the core is externally coated with an interlayer and a shell layer in sequence; the interlayer is of a multi-layer laminated structure formed by positive electricity interlayers and negative electricity interlayers alternately, the first layer in the laminating direction of the laminated structure is the positive electricity interlayer, and the last layer in the laminating direction of the laminated structure is the negative electricity interlayer; the positive electricity interlayer is made of polyethyleneimine; the negative electricity interlayer is quantum dots; the shell layer is SiO2 modified by carboxyl; the carboxyl of the shell layer is coupled with a specific antibody. The magnetic nanoprobe disclosed by the invention has strong magnetic responsiveness, high fluorescence signal and specific bacterium capturing capacity, realizes rapid capturing of to-be-detected substances such as food-borne pathogenic bacteria in a to-be-detected sample, and has huge application potential in the field of rapid detection of food-borne bacteria.