35results about How to "Good resistance to photobleaching" patented technology

The invention discloses a preparation method for monophosphate-adjuvant water-soluble fluorescent carbon quantum dot solid powder, which belongs to the technical field of nanometre materials. The preparation method comprises the following steps of: by taking soluble phosphate solution as an adjuvant, taking saccharides, amino acids and some low-molecular-weight organic matters containing hydroxyl and carboxyl as reaction precursors and adopting a microwave heating means, directly preparing solid carbon quantum dot powder in one step; and adding an appropriate amount of ethanol aqueous solution to precipitate and removing most of salts, then performing further purification by virtue of strong-base anion exchange resin and strong-acid cation exchange resin sequentially, centrifuging and then performing rotary evaporation on the supernatant, so as to obtain the purified carbon quantum dot solid powder. The carbon quantum dots prepared by the preparation method disclosed by the invention are good in solubility in water, and solid powder samples can be stored for a long time; meanwhile, the obtained carbon quantum dots further are also excellent in water solubility and fluorescence characteristic. The whole preparation process is simple to operate, requirements on equipment are low, and raw materials are low in cost, wide and easily available; the preparation method is an environment-friendly preparation method for carbon quantum dots.

The invention belongs to the technical field of fluorescent nano-materials and provides a red fluorescent copper nano-cluster and a preparation method thereof, which have the advantages of simplicityin operation, moderate conditions and the quantum yield of 0.44 percent. A synthesis method of the prepared red fluorescent copper nano-cluster is simple, and interference caused by self fluorescent light of living organisms can be avoided; the red fluorescent copper nano-cluster has high sensitivity on Ag<+> ions and can be used for constructing a sensing system for detecting the Ag<+> ions. At room temperature, N-acetyl-L-cysteine is used as a protection agent and a reduction agent and a copper nitrate solution is used as a matrix to prepare a fluorescent copper nano-cluster solution throughan ultrasonic method. The addition of a common reduction agent, i.e., sodium borohydride, ascorbic acid, a surfactant and the like is avoided; the preparation method is simple to operate and feasible, has moderate conditions and is environmentally friendly; the prepared copper nano-cluster has good water solubility, high quantum yield and low toxicity, and can be used for highly sensitively and highly selectively identifying and detecting the Ag<+> ions; a detection process is simple and rapid and a detection result is accurate.

The invention provides a non-conjugated fluorescent polymer. The non-conjugated fluorescent polymer comprises a repeated unit shown as a formula (I), wherein M is selected from two formulas shown in the description; N is selected from a formula shown in the description; n' is selected from 1 to 20; Q is selected from eight formulas shown in the description; R is alkyl with the carbon number of 1 to 10; and n is selected from natural numbers of 3 to 150. (The formula (I) is shown in the description.).

The invention discloses a fluorescent probe and application thereof. The fluorescent probe is provided with a structure shown as a formula I or a stereoisomer of the fluorescent probe, wherein R1 is hydrogen, alkyls of C1 to C6, phenyl or alkyl-substituted phenyl; R2 to R9 are independent hydrogen atoms, alkyls of C1 to C6, halogenated alkyls of C1 to C6 and alkoxys or hydrogen atoms of C1 to C6;R10 and R11 are independent sulfo or sulfo-substituted alkyls of C1 to C6; X1 and X2 are independent carbon, oxygen, sulfur, selenium or tellurium. The fluorescent probe has the specific advantages ofgood biocompatibility, low cytotoxicity, small damage to a biological sample and good photobleaching resistance; long-time effective observation of a cell sample can be realized without influence from a pH value of a cell.

The invention provides a near infrared fluorescent probe substrate material of rare earth ion nano alkali metal rare earth fluoride and a preparation method of the near infrared fluorescent probe substrate material. The chemical formula of the material is MRe (1-x-y) Rm (x) YbyNdzF4, wherein the M is one or more of Li, Na and K, the Re is one or more of Gd, La, Y and Lu, and the Rm is one or more of Er, Tm, Tb and Ho. The material is prepared through a solvothermal method and a hydro-thermal method, efficient near infrared light of 980 nm of a wave band can be obtained under the excitement of infrared light of 730 nm and 800 nm of wave bands, and upconversion fluorescence visible to near infrared light wave bands can be obtained under the excitement of infrared light of 980 nm and 800 nm of wave bands. Therefore, the material can serve as an upconversion fluorescence probe and a downconversion fluorescence probe for fluorescence imaging after being packed and subjected to surface decoration, and the material can serve as magnetic resonance imaging when a substrate contains magnetic element Gd.

The invention relates to a preparation method of a fluorescent carbon dot capable of imaging RNA in a living cell for a long time in a targeting manner and a product and application of the preparationmethod, the fluorescent carbon dot is hydro-thermally synthesized from m-phenylenediamine, an amine compound and water as the raw materials; the synthesis method is simple, the conditions are controllable, the prepared carbon dot has the performances of strong green fluorescence emission, ultralow biotoxicity and strong photobleaching resistance, can image the RNA in the cell for a long time, canserve as an RNA probe to distribute and locate the RNA in the conventional cell, or is applied to the dynamic change of the RNA in the cell, and can further be used to indicate the state of the celland screen an anti-cancer drug taking RNA polymerase I as a target spot.

The invention discloses a method for preparing synthetic sulfur-phosphorus co-doped graphene quantum dots and relates to preparation of nano materials. The method comprises the following steps: respectively putting citric acid monohydrate, sodium phytate and anhydrous sodium sulfate into a container, further adding deionized water, and stirring and dissolving so as to obtain a clear solution; transferring the obtained clear solution into a high-pressure kettle, performing hydrothermal treatment, and naturally cooling to a room temperature so as to obtain a dark yellow solution; transferring the obtained dark yellow solution into a centrifugal tube from the reaction kettle, and removing relatively large suspended granules through centrifugation so as to obtain supernate; performing suctionfiltration on the obtained supernate after centrifugation, and transferring the obtained yellow filtrate into a dialysis bag for dialysis; freezing the solution after dialysis, and further performingfreeze-drying on the obtained solid product, thereby obtaining the sulfur-phosphorus co-doped graphene quantum dots. The citric acid is adopted as a carbon source, the sodium phytate is adopted as a phosphorus source and the sodium sulfate is adopted as a sulfur source for the first time, and S,P-GQDs are synthesized through a simple one-step hydrothermal method.

The present invention relates to ligands, nanocrystal complexed with said ligands and their use for bio-imaging.

The invention discloses a method for one-step synthesis of fluorescent carbon dots with tea leaves as a carbon source and application of the fluorescent carbon dots, and relates to the technical field of carbon dot synthesis, the technical key point is that the method specifically comprises the following steps: S1, carbon source pretreatment: Tieguanyin tea residues and green tea residues are cleaned, dried and prepared into powder; s2, carbon dot synthesis: weighing 0.3000 g of Tieguanyin tea residue powder and 0.3000 g of green tea residue powder, respectively pouring the Tieguanyin tea residue powder and the green tea residue powder into different polytetrafluoroethylene high-pressure reaction kettles, adding distilled water, and putting the polytetrafluoroethylene high-pressure reaction kettles into a constant-temperature blast drying box for a synthesis reaction. The green tea and the Tieguanyin tea are used as raw materials, the fluorescent carbon dots are synthesized through a one-step hydrothermal method, by optimizing the optimal temperature and time for preparing the carbon dots, the synthesized carbon dots have pH dependence and meanwhile show good fluorescence performance, photobleaching resistance, salt resistance and water solubility, the synthesis process is simple, consumed time is short, and the raw materials are low in price and easy to obtain; in addition, the method can be applied to research and development, preparation, fluorescence analysis and biological marking of novel fluorescent carbon nanomaterials.

The invention relates to a phosphorescent iridium complex with a lysosome targeting function and its preparation method and use and belongs to the technical field of organic photoelectric materials. The phosphorescent iridium complex comprises a C^N ligand, a metal core and an alkyl chain-containing auxiliary ligand and has a structural formula shown in the description. The phosphorescent iridium complex can be excited by visible light, produce emission light in a near infrared area and reduce an excitation light source-caused damage to a biological sample and has deep tissue penetrating depth. The phosphorescent iridium complex has good photobleaching resistance and realizes long-term effective observation of cell tissue. The phosphorescent iridium complex can be used in the field of lysosome labeling and bioimaging, has a simple chemical structure and good biocompatibility and is a good lysosome targeting phosphorescent probe.

The invention belongs to the field of fluorescence sensors, and relates to a nitrogen-doped carbon dot, in particular to a preparation method and application of a nitrogen-doped carbon dot based on a listeria monocytogenes source. The method is based on nitrogen-doped carbon dots (NCDs-LM) derived from Listeria monocytogenes. The NCDs-LM is successfully synthesized by adopting a one-step solvothermal method. The fluorescence intensity of the NCDs-LM-based fluorescence sensor and the I <-> concentration have a good linear relationship, and the detection limit is 20 nmol/L. The sensor has been successfully applied to detection of I <-> in drinking water and milk samples. Meanwhile, the NCDs-LM-based sensor can be used for pH detection, and the detectable pH linear range is wide. In addition, fluorescent test paper based on NCDs-LM is designed and used for semi-quantitative detection of I <-> and pH through a naked eye colorimetric method. The research shows that the NCDs-LM-based fluorescence sensor has great application potential in the aspects of environmental monitoring and food analysis.

The invention provides a fluorescent probe used for cell membrane imaging, and a preparation method and application of the fluorescent probe. The structural formula of the fluorescent probe consists of three parts: polypeptide RGD, a tetraphenyl ethylene derivative MTY and palmitic acid modified polypeptide Pal-RRRR; the RGD is combined with integrin protein on a cell membrane through ligand-receptor interaction; Pal is inserted into lipid on the cell membrane through hydrophobic interaction; and the RRRR is combined with the cell membrane with negative charges through electrostatic interaction, so that accurate and firm imaging of the cell membrane is realized. The fluorescent probe has the characteristics of high light stability, high fluorescent brightness, high impermeability and the like, and can carry out rapid imaging; and in addition, the fluorescent probe shows an obvious aggregation-induced luminescence phenomenon and excellent photobleaching resistance in practical application, can realize long-time fluorescence imaging, has the characteristics of a simple preparation technology, convenience in operation and a low cost, and has a huge application prospect in the field of biomedical imaging.