298 results about "Nanoprobe" patented technology

The invention relates to a surface-enhanced Raman scattering probe and a preparation method thereof. The probe is an interlayer structure and consists of a core precious-metal nano-rod, an intermediate sandwich layer and a precious-metal shell layer which grows and is formed on the outer surface, wherein a Raman signal molecule is wrapped inside the intermediate sandwich layer. The preparation method comprises the following steps that: the surface of the precious-metal nano-rod absorbs or is coupled with the Raman signal molecule, then the Raman signal molecule is wrapped to form the intermediate sandwich layer through silicon dioxide or polyelectrolyte, and then the precious-metal shell layer grows and is formed outside the intermediate sandwich layer. Through the surface-enhanced Raman scattering probe with the sandwich structure, strong local electromagnetic density is produced through the interaction of the surface plasma between the gold nano-rod and the outer metal shell layer, so the Raman signal is greatly enhanced, the weaknesses that a two-dimensional underlay is difficult to repeat, is expensive and is complicated can be overcome, and at the same time the size of the surface-enhanced Raman scattering probe is smaller than 200nm, biological detection of living bodies and application of biological imaging can be facilitated when the surface-enhanced Raman scattering probe is used as a biological probe.

Second harmonic nanoprobes for imaging biological samples and a method of using such probes to monitor the dynamics of biological process using a field resonance enhanced second harmonic (FRESH) technique are provided. The second harmonic generating (SHG) nanoprobes are comprised of various kinds of nanocrystals that do not possess an inversion symmetry and therefore are capable of generating second harmonic signals that can then be detected by conventional two-photon microscopy for in vivo imaging of biological processes and structures such as cell signaling, neuroimaging, protein conformation probing, DNA conformation probing, gene transcription, virus infection and replication in cells, protein dynamics, tumor imaging and cancer therapy evaluation and diagnosis as well as quantification in optical imaging.

The invention relates to a nano probe for copper ion fluorescence imaging in cells and a preparation method for the nano probe. The preparation method comprises the following steps: firstly, synthesizing up-conversion nana particles with core-shell structures, CS-UCNPs for short; then, by taking a CTAB (cetyltrimethyl ammonium bromide) as a template agent and a surfactant, coating a layer of mesoporous SiO2 on the surfaces of the CS-UCNPs to obtain mesoporous coated nano particles CS-UCNPs@mSiO2 with compounding functions; finally, performing covalent bond assembly on functional modified rhodamine organic dye RHB precursors capable of identifying metal copper ions in a singular manner and the CS-UCNPs@mSiO2 to construct an organic-inorganic hybrid nano probe CS-UCNPs@mSiO2-RBH, thereby realizing fluorescence detecting and living cell fluorescence imaging of copper ions in an aqueous solution. The preparation method disclosed by the invention has the advantages of being simple in process, convenient to operate and easy to control structure. The prepared nano fluorescence probe has the characteristics of a uniform dimension, a stable structure, low toxicity and good biocompatibility, and a potential application value in the fields of up-conversion fluorescence labeling, fluorescence detecting and the like of cells or tissues.

The invention relates to preparation and application of a fluorescent carbon dot nanoprobe for detecting free chlorine in water. The free chlorine in the water is detected by quenching a fluorescent signal by taking nitrogen and sulfur co-doped carbon dots (N,S-CDs) which are synthesized by citric acid (CA) and L-gystein as raw materials as the fluorescent probe. Experimental conditions such as concentration of S-CDs, response time, pH value of a solution and the like are optimized. Under the optimized condition, the fluorescent strength quenching extent of the system and the concentration of the free chlorine represent a good linear relationship: [R<2>=0.9945] in a range of 0.01-100micro mol / L and the detection limit is 5nmol / L. As an effective method for detecting the free chlorine in the water, the method shows a remarkable advantage, has the characteristics of simplicity, low cost, greenness, high selectivity, rapidness, sensitivity and the like and is successfully applied to detecting the free chlorine in local tap water and swimming pool water in Guilin. The sensing method has a broad application prospect in water quality analysis in the field of environment analysis.

The invention discloses preparation and application of an SERS-fluorescence dual-mode optical imaging probe with a tumor double-targeting function. The nano-probe is composed of an imaging function core part and a targeting function shell part. The imaging function core part comprises silver nanoparticles adsorbed with Raman reporter molecules and a silicon dioxide shell layer doped with fluorescence dye, so that the probe has the SERS imaging function and the fluorescence imaging function simultaneously. The targeting function shell comprises a polyethylene glycol (PEG) coupling agent and two polypeptides specifically targeting tumor cells. According to the probe, the more effective targeting capacity is supplied to the nanoparticles by adopting a dual-polypeptide modification method, therefore, the probe can well enter the tumor cells, recognition of the probe to the tumor cells is enhanced, and SERS-fluorescence dual-mode imaging on a tumor is achieved.

The invention relates to an unicell detector based on a nano fiber probe, which comprises a nano probe, a light source unit, a micro operation system, an electricity detection unit, a cellular localization system and a photon detection unit, an innermost layer of the nano probe is a fiber layer, the outer wall of the fiber layer is wrapped with a nano ring electrode layer, and the outer wall of the nano ring electrode layer is wrapped with an insulating layer. A manufacturing method of the unicell detector based on the nano fiber probe comprises the steps of drawing, sputtering, making the insulating layer and cutting focused ion beam. The unicell detector has high sensitivity and can realize the unicell grade detection, compared with a traditional detection means by crushing millions of cells, the required cell sample amount is greatly reduced, and the success rate of disease detection at early stage can be increased. The unicell detector can perform in-vivo cell detection and can avoid the false appearance generation during a cell processing process. The space-time resolution and detectable target object scope can be greatly enhanced, and a biochemistry mechanism in the unicell enables real-time detection and analysis.

Functionalized second harmonic nanoprobes for imaging samples and a method of using such probes to monitor the dynamics different processeses using a variety of imaging techniques are provided. The functionalized second harmonic generating (SHG) nanoprobes are comprised of various kinds of nanocrystalline materials that do not possess an inversion symmetry and therefore are capable of generating second harmonic signals that can then be detected by conventional two-photon microscopy, and are provided with functional surface modifications that allow for targeted imaging of a variety of biological and non-biological processes and structures such as cell signaling, neuroimaging, protein conformation probing, DNA conformation probing, gene transcription, virus infection and replication in cells, protein dynamics, tumor imaging and cancer therapy evaluation and diagnosis as well as quantification in optical imaging.

The invention discloses a single-cell / single-molecule imaging light / electricity comprehensive tester based on a multifunctional probe. The tester comprises the multifunctional nano-probe, a sample pool, an atomic force microscope system, a light source unit, an electricity testing unit, a cell sample locating system and a photon testing unit. The light source unit, the electricity testing unit, the cell sample locating system and the photon testing unit are respectively connected with a data collection and analyzing unit. The multifunctional nano-probe comprises an optical fiber layer, a nano electrode layer and an insulation layer. The nano electrode layer and the insulation layer are wrapped on the outer wall of the optical fiber layer in sequence. The synchronization comprehensive tester comprises a manufacturing method of the nano-probe which can carry out atomic force scanning imaging on single-cells / single-molecules and carry out light / electricity testing at the same time, a manufacturing method of the sample pool and relevant optics, electricity and mechanics testing and analyzing instruments. Temporal-spatial resolution and the range of target objects which can be tested are greatly improved, the tester can be widely used in biology and medicine and be used for fundamental research and disease testing under the level of sub-cells and molecules, and the tester has great development significance on tumor early diagnosis, medicine development and agricultural science.

The invention relates to a method for directly detecting p53 gene mutation in lung cancer samples based on nanoprobe. The method is characterized in that sandwich hybridization is carried out to an unmarked target nucleic acid sequence, a signal probe marked by nano gold and a capture probe connected with a solid-phase holder and the amplification effect of silver staining enhanced nano-gold signals is used for generating highly sensitive identification signals. The method can detect single base mutation in non-amplified genomic DNA samples. Compared with traditional method based on fluorescence signal detecting, the nano chip detecting method greatly enhances the sensitivity and specificity of detection and hybridization signals can be collected and analyzed by an ordinary optical scanner or a charge-coupled device (CCD) digital camera or analyzed by related software to obtain detecting reports.

The invention discloses an upconversion super-resolution imaging nanoprobe as well as a preparation method and application thereof. The upconversion super-resolution imaging nanoprobe has a core@shellstructure. The preparation method comprises the following steps: preparing rare-earth upconversion nano-particles with controllable particle size and excellent dispersion property by adopting a solvothermal method; performing surface modification by polyacrylic acid; and finally performing protein modification. The upconversion super-resolution imaging nanoprobe is applied to immunofluorescent labeling of a subcellular structure of cells, so that fluorescent super-resolution imaging of the subcellular structure is realized. Compared with the traditional fluorescein-based super-resolution optical imaging method, the method disclosed by the invention is a fluorescence zero-bleaching and zero-flicker super-resolution microscopic imaging method based on the upconversion super-resolution imaging nanoprobe, and biological samples can be observed for a long time.

The invention belongs to the preparation field of nanoprobes, particularly relates to a method for preparing magnetic fluorescent graphene composite nano ion probes, wherein the magnetic fluorescent graphene composite nano ion probes comprise magnetic graphene and fluorescent nanoparticles, magnetic nanoparticles are excellent superparamagnectic ferroferric oxide nanoparticles, the fluorescent nanoparticles are water soluble quantum dots capable of adjusting fluorescence color, the whole magnetic fluorescent graphene composite nano ion probes have dual purposes of magnetism and fluorescent, fluorescent quantum dots are uniformly distributed on the surface of a magnetic grapheme lamellar structure, the particle sizes of the magnetic nanoparticles are 10-200nm, and the particle sizes of the quantum dots are 1.5-10nm. The method for preparing the magnetic fluorescent graphene composite nano ion probes can achieve rapid detection and separation of copper ions through the magnetic performances of specific molecular ligands decorated on the surfaces of the quantum dots and magnetic nanoparticles. The magnetic fluorescent graphene composite nano ion probes are simple, rapid and sensitive copper ion specific detection reagents, and have wide application prospect in biomolecule detection and separation fields.

The invention discloses a surface self-assembly gold nanoprobe with the free radical capture performance and a preparing method and the application thereof. The surface self-assembly gold nanoprobe with the high free radical capture performance is prepared by the following steps: the surface of a gold nano-particle is connected with nitrone free radical probe ligand with the structure of formula II by a connexon of the structure of formula I. The nitrone free radical probe ligand is connected with R3 radical group end. The gold nano-particle is connected with sulfhydryl end of the connexon. In formula Ia and formula Ib, R3 is -OH, -NH2 or -COOH, n is equal to 2-11, and n1 is equal to 1-4. In formula IIc, R1 is -P(O)(OC2H5)2, and R2 is OH, COOH or CH2OH. The surface self-assembly gold nanoprobe with the high free radical capture performance can capture free radicals under low concentration and can be applied as an antioxidant.

The present invention relates to SPM nanoprobes and the preparation method thereof, more particularly, to SPM nanoprobes comprising a spheroid deposit capped-nanoneedle bonded to one end of a mother tip, wherein the spheroid deposit is formed by particle beam induced deposition and is characterized in that the ratio of the diameter of the spheroid deposit to that of the nanoneedle is in the range of 1.5 to 8.5. The SPM nanoprobe according to the present invention is capable of imaging or measuring an irregularly curved or complicated surface, pattern and / or a frictional or adhesive force thereof and controlling size of a spheroid deposit formed at the end portion of nanoneedle and the ratio of the diameter of the spheroid deposit to that of the nanoneedle arbitrarily.

The invention discloses a multifunctional nanoprobe for targeting SERS (surface enhanced Raman scattering) imaging of tumor cells and a preparation method thereof. The probe comprises gold nanoparticles, thiosalicylic acid, polypeptide and bovine serum albumin sequentially from inside to outside, the gold nanoparticles are wrapped with a layer of thiosalicylic acid molecules and then connected with the polypeptide through an amido bond, and finally the surface is wrapped with a layer of the bovine serum albumin to enclose the exposed area of the surface of the probe to obtain the nanoprobe; the gold nanoparticles are star-like gold nanoparticles. The preparation method includes: firstly, preparing the star-like gold nanoparticles high in near-infrared absorption performance, secondly, modifying the surfaces of the gold nanoparticles with Raman molecules, and thirdly, further binding the polypeptide capable of specifically binding the tumor cells. The probe integrates multiple functions, has targeting SERS imaging performance and a photothermal therapy function, can effectively recognize the tumor cells in a directional manner, performs tumor imaging, and utilizes the photothermal therapy to kill the tumor cells.

The invention discloses a method for preparing bifluorescence emission nano-probes in a post-encoding mode. A fluorescent probe precursor which can be used for post-encoding is synthesized by taking cadmium telluride quantum dots and gold nanoclusters as fluorescence encoding elements and silicon balls as a carrier of the encoding elements according to the fluorescent characteristics of the quantum dots and the gold nanoclusters; and then an optical regulator is added into the precursor in a post-encoding mode to prepare the bifluorescence emission nano-probes. The fluorescence intensity ratio of two encoding elements in the obtained bifluorescence emission nano-probes is relatively large, so that the observation on the change of a fluorescent signal at relatively high resolution is facilitated. The method for preparing the bifluorescence emission nano-probes comprises the following steps of: preparing the quantum dots, wrapping silicon on the quantum dots, synthesizing the gold nanoclusters, synthesizing fluorescent probe precursor microspheres, and preparing the bifluorescence emission nano-probes. The invention has the advantages that the synthetic method is simple; the encoded probes have the irreversibility; the reproducibility of different batches of probes is high; and an effective method for preparing a large number of bifluorescence emission nano-probes which can be used for fluorescent imaging is provided.

The invention discloses a transmission electron microscope sample table of an in-situ measurement nanometer device. The transmission electron microscope sample table comprises a metal nanoprobe, an insulating plug piece and a sample supporting table, wherein the front and reverse surfaces of the insulating plug piece are provided with a plurality of metal electrodes respectively; the corresponding metal electrodes are conductively connected through metallized through holes; one end of the sample supporting table is connected with the insulating plug piece, and the other end of the sample supporting table is provided with a sampling region and a testing region; the testing region is a metal electrode which is arranged on the surface of the sample supporting table and is suspending; the metal electrode of the sample supporting table is conductively connected with the metal electrode of the insulating plug piece; the metal nanoprobe, the testing region metal electrode and a tested sample form a three-end field effect transistor. According to the transmission electron microscope sample table, the sample can be observed under the atomic-scale resolution and electrical measurement is performed in real time, and the electrical property and the nanostructure change of a unit to be measured are disclosed in situ.

The invention discloses a preparation method and an application of a magnetic graphene oxide-nanogold label-free complex. On the basis of different adsorption effects of magnetic graphene oxide on single-stranded DNA and double-stranded DNA, after small target RNA is added, an identification section of DNA1 is specifically bound to the small target RNA, so that a DNA / RNA double-stranded structure is formed and a gold nanoprobe, which is adsorbed on the surface of the magnetic graphene oxide, is dissociated in a solution. Through magnetic separation, on the basis of a developing effect of nanogold in a visible light region, the color change of the nanogold solution in a supernatant, along with different small RNA concentrations, is observed; and through quantitative analysis by virtue of an ultraviolet-visible spectrophotometer, rapid colorimetric detection, with high sensitivity and high specificity, on the small RNA is achieved.

The invention discloses NOBF4 modified up-conversion nanoparticles, a Dye-NOBF4-UCNPs nanometer probe, preparation methods of the nanoparticles and the Dye-NOBF4-UCNPs nanometer probe, and a sulfur-containing compound detection method. The preparation method of the NOBF4 modified OA-NaGdF4:Yb,Er@OA-NaGdF4:Yb,Nd comprises: 1) carrying out a co-precipitation reaction on a sodium-containing alkalinecompound, 1-octadecene, oleic acid, a neodymium source, an ytterbium source, a gadolinium source, NH4F and OA-NaGdF4:Yb,Er to obtain OA-NaGdF4:Yb,Er@OA-NaGdF4:Yb,Nd up-conversion nanoparticles; and 2)carrying out a contact reaction on the OA-NaGdF4:Yb,Er@OA-NaGdF4:Yb and NOBF4. According to the present invention, the nanometer probe has advantages of wide detection range, high sensitivity, good selectivity, low cost, rapid detection and the like in detection of sulfur-containing compounds.

The invention belongs to the technical field of nano probes, and particularly provides an up-conversion luminescence-thermo-chemotherapy composite nano probe as well as a preparation method and application thereof in combined treatment programmed control. The up-conversion luminescence-thermo-chemotherapy composite nano probe adopts two layers of rare-earth fluoride as a core, an intermediate layer is a hollow silicon dioxide shell layer loaded with a photo-thermal material, an outer layer is an organic molecular membrane loaded with a micromolecular chemotherapy drug, and a structural generalformula is NaL1-x-yYbxEryF4@NaLF4@SiO2-M@N-P. When the nano composite material provided by the invention is illuminated by near-infrared rays, photo-thermal molecules generate the heat energy to promote the dissociation of a thermosensitive coating, so that the chemotherapy drug molecules are released, the cancer chemotherapy is realized, the heat energy generated by the photo-thermal molecules can also thermally kill the cancer cells, the drug release and the photo-thermal treatment in the combined cancer treatment can be performed in a programming step-by-step manner, and the dosage of thechemotherapy drug and the heat energy can be reduced by utilizing the strategy.

The invention discloses a COVID-19 IgG / IgM detection kit, a detection card, a rare earth nanoprobe and a preparation method thereof, the rare earth nanoprobe is praseodymium-doped gadolinium lutetiumfluoride coated sodium yttrium fluoride with a core-shell structure, the particle size is 40 nm-60 nm, the rare earth nanoprobe is composed of NaGdxLu1-y-xF4:yPr coated NaYF4, wherein NaGdxLu1-xF4 isa matrix, and the doping ion is Pr<3+>; wherein the colon : means praseodymium doping; wherein x and y are rare earth ion doping mole percentages, x ranges from 20% to 90%, and y ranges from 1% to 10%; wherein NaYF4 is a shell layer, @ is characterized in that NaYF4 is coated on the surface of NaGdxLu1-y-xF4: yPr. The nanoprobe is a rare earth fluoride nanomaterial and has the advantages of beinglow in background, long in light-emitting service life, strong in fluorescence signal, high in signal-to-noise ratio and the like, the probe is connected with a new coronavirus recombinant antigen through a covalent bond, a labeled product is stable, and the nanoprobe has the advantages of being high in sensitivity, high in accuracy, rapid, easy and convenient to detect and the like. Early new coronavirus suspected patients can be screened and detected, and clinical definite diagnosis can be quickly and specifically assisted.

Methods and computer program products for super-resolution mapping of nanoprobes having spectrally distinguishable coherent scattering properties. A sample containing a plurality of nanoprobes is illuminated with broadband light, and coherent scattering by the nanoprobes is detected. Scattered light is spectrally associated with respective nanoprobes, allowing a position associated with each nanoprobe to be mapped.

A nano-capsule construct for imaging and therapeutic uses and method for production are provided. One nano-probe embodiment based on genome-depleted plant brome mosaic virus (BMV) whose interior is doped with indocyanine green (ICG), an FDA-approved near infrared fluorescent dye, is used to illustrate the invention. The material encapsulated in viral shell components may be coated with functionalized coatings such as branched, dendritic polymer coatings to improve longevity and distribution in the body as well as antibody conjugation for increased target specificity. The constructs can also be coated with ferromagnetic iron oxide nanoparticles, enabling the ICG-containing capsules to be used as nano-probes with the capability of being detected in both optical and magnetic resonance imaging. The capsules may be produced by purifying a plant or animal viruses and disassembling the viruses to provide virus shell components. The virus shell components are reassembled in the presence of a material for encapsulation thereby encapsulating said material within the core of the construct in one embodiment.

The invention discloses a composite nanoprobe with a dumbbell structure as well as a preparation method and application of the composite nanoprobe. The composite nanoprobe comprises a gold nanorod, solid silicon dioxide wrapping the two ends of the gold nanorod, mesoporous silicon dioxide wrapping the solid silicon dioxide and indocyanine green loaded in the mesoporous silicon dioxide; the gold nanorod, and the solid silicon dioxide and the mesoporous silicon dioxide which are positioned at two ends of the gold nanorod can form the dumbbell structure. The composite nanoprobe has the advantagesthat under the stimulation of near-infrared light the enhanced local electric fields at the two ends of the gold nanorod stimulate ICG molecules in the mesoporous silicon dioxide to continuously generate singlet oxygen, and meanwhile, the enhanced photo-thermal and photodynamic effects are finally obtained by utilizing the double photo-thermal effects of the gold nanorod and ICG, so that tumor cells can be effectively killed under lower laser power. In addition, ICG molecules under the protection of the gold nanorods and the mesoporous silicon dioxide do not generate photobleaching, and goodphotostability is achieved.

The invention relates to a preparation method of a fluorescent nanoprobe based on a two-dimensional lanthanum metal organic skeleton MOF-La, a prepared probe material and application of the prepared probe in a biosensor. The preparation method comprises the following preparation steps: (1) in an alkali solution, adding 2,2'-thiodiacetic acid or 2,2'-thiodiacetin, La<3+> lanthanum ion inorganic salt, and reacting for 10 to 30 h at the temperature of 120 to 180 DEG C; adding an obtained crystal into an organic solvent, carrying out ultrasonic treatment, performing centrifugation, dispersing into an organic solution of n-butyllithium, and reacting for 15 to 25 h at the temperature of 20 to 30 DEG C under the protection of inert gas, so as to obtain a two-dimensional MOF-La nanomaterial; dispersing the two-dimensional MOF-La nanomaterial in a buffer solution, adding fluorescently-labeled nucleotide chains, and performing centrifugation after reaction at room temperature to obtain the material. The preparation method is simple in preparation conditions, convenient in operation and low in cell toxicity, and the obtained probe has the characteristics of high selectivity and high sensitivity, so that a false positive result is avoided, qualitative performance and quantitative performance are more accurate, and the probe has a good application prospect.

The invention provides a tumor mitochondrial targeting magnetic nanoprobe, and a preparation method and an application thereof. In the preparation method of the tumor mitochondrial targeting magneticnanoprobe provided by the invention, cyanine dye molecules are compounded on the surface of Fe3O4 nanoparticles by covalent crosslinking, so that the prepared nanoprobe has good stability, monodispersity and good biocompatibility and targeting effect, and can be used not only in biological in-vivo imaging, but also as tumor diagnostic and therapeutic preparations, carriers and magnetic separationmaterials. At the same time, the preparation method is simple in process and suitable for promotion and large-scale production.

The invention relates to a near-infrared second region fluorescent nanoprobe based on black phosphorus as well as a preparation and application of the near-infrared second region fluorescent nanoprobe. The preparation method of the near-infrared second region fluorescent nanoprobe comprises the following steps: uniformly mixing red phosphorus or black phosphorus with a ball-milling body and then carrying out ball milling for 1 to 200 hours; then adding a hydrophobic ligand into a mixture and continuously carrying out ball milling for 1 to 200 hours to obtain black phosphorus nanoparticles, thesurfaces of which are modified with the hydrophobic ligand; dissolving the black phosphorus nanoparticles modified with the hydrophobic ligand on the surface and the amphipathic molecules into a volatile organic solvent according to the mass ratio of 1 to (100 to 200); then volatilizing to remove the organic solvent, uniformly mixing the obtained substance with water and vigorously stirring to obtain water-soluble near-infrared second region fluorescent nanoprobe based on the black phosphorus. The near-infrared second region fluorescent nanoprobe obtained by the preparation method disclosed by the invention has the advantages of stronger and wider fluorescent signal, capability of achieving multi-wavelength excitation and multi-wavelength emission and broad application prospect in biological imaging.

The invention discloses a preparation method of a thrombin photoelectrochemical sensor based on a cyclometalation Ir(III) coordination compound. According to the sensor, a cyclometalation iridium coordination compound is used as a photoelectro active material, through an Au-S key, the cyclometalation iridium coordination compound is assembled on nanometer gold, and a nanometer probe is prepared. According to a thrombin recognizing system, combination of an aptamer and thrombin is adopted to produce proximity effects to initiate DNA replacement, when the thrombin exists, the local concentrationof single-stranded DNA S1 and single-stranded DNA S2 containing thrombin aptamer fragments is increased, S1 / T hybridized in advance and the S2 are induced to generate a strand displacement reaction,and single chain T is released. The released T is hybridized with a capture barrette H1 fixed on a working electrode, the self-assembly reaction of the barrette is initiated and catalyzed, a large quantity of H1 / H2 hybridization chains are formed on the surface of the working electrode, the single-stranded DNA exposed at the terminal is used for capturing a signal nanometer gold probe, response ofphotocurrent signals is realized, and the thrombin photoelectrochemical sensor has high sensitivity and favorable selectivity.

The invention provides a novel three-modal prostate cancer targeted nanoparticle developer and a preparation method thereof. With ultra-micro-particle-size organic melanin nanoparticles (UMNPs) with endogenous and high biological compatibility as a carrier, a small molecular group with a PSMA targeting function is coupled with nanoparticles to obtain a nanometer molecular image probe PSMA-PEG-UMNPs with the prostate cancer targeting function; nuclide<89>Zr and T1 weighted magnetic resonance contrast agent Mn<2+> are marked directly by using a UMNPs surface active group to obtain a nanoprobe (<89>Zr, Mn)-PSMA-PEG-UMNPs with PAI, MRI and PET three-mode imaging functions. The probe can be specifically bound with a PSMA antigen on the surface of a prostate cancer cell; the PSMA high-expressiontissues are located accurately by optical, nuclear magnetic and nuclear medicine ways; and thus targeted multi-modal molecular imaging diagnosis of tumors is realized.

The invention discloses a preparation method of a CdSe@ZnS / AgNCs composite fluorescent nanoprobe. CdSe@ZnS quantum dots are mixed with nano-silver clusters under a certain pH condition to prepare theCdSe@ZnS / AgNCs composite fluorescent nanoprobe with the CdSe@ZnS quantum dot concentration of 0.032 mg / mL and the nano-silver cluster concentration of 0.015 mg / mL. The CdSe@ZnS / AgNCs composite fluorescent nanoprobe constructed by directly mixing the CdSe@ZnS quantum dots and nano-silver clusters has the advantage of simple synthesis method. The constructed CdSe@ZnS / AgNCs composite fluorescent nanoprobe realizes oxidative degradation of the silver clusters through hydrogen peroxide to release silver ions, and the silver ions have a quenching effect on fluorescence of the CdSe-ZnS quantum dots,so the efficient detection target of hydrogen peroxide is achieved, thereby the technical problems of long detection reaction time, slow response and insufficient low detection limit of traditional technologies are solved.

The invention relates to a SERS sensor based on an Au-Se interface for quantitative detection of ultra-sensitive and high-fidelity biological molecules. The TAMRA-modified SeH-polypeptide chain is assembled on the surface of AuNPs through Au-Se. Due to the surface plasmon resonance effect, TAMRA exhibits a strong Raman signal, the peptide chain is cleaved by activated MMP-2 when MMP-2 is present,and TAMRA signaling molecules are far away from AuNPs, which leads to the reduction of Raman signals. Compared with Au-S Raman nanoprobes, Au-Se SERS sensor has better resistance to biothiol interference. The invention uses a new type of bonding method to form a more stable Au-Se SERS sensor, which can provide a new strategy for high-sensitivity and high-fidelity detection of biomolecules in complex physiological systems. A SERS sensor with a core-shell structure modified with an internal standard can be used for absolute quantitative detection of living cells.