28 results about "Thiomalic acid" patented technology

The invention relates to the technical field of in-vitro diagnostic kits, in particular to carboxyl polystyrene microspheres, a preparation method and application of the carboxyl polystyrene microspheres in a kit for quantitatively detecting MxA. The preparation method of the carboxyl polystyrene microspheres comprises the steps that firstly, polystyrene microspheres with the surface rich in aldehyde groups are prepared through a soap-free emulsion polymerization method; then carrying out a Schiff alkali reaction with 2-aminoethyl methacrylate hydrochloride to carry out double bond modification on the surface of the microsphere, and meanwhile, improving the hydrophilicity of the microsphere by an ester group and an imino group; and finally, carrying out sulfydryl-double bond addition reaction on the polystyrene microspheres and mercaptosuccinic acid to generate the polystyrene microspheres rich in carboxyl on the surfaces. The carboxyl polystyrene microspheres prepared by the invention can improve the binding efficiency of latex and an MxA antibody, so that the detection sensitivity is improved, the purpose of high-sensitivity quantitative detection of MxA protein can be achieved, and the detection time is greatly shortened.

According to the copper alloy strip residual stress rapid evaluation and improvement method based on stress feedback, a warping measurement value is accurately mapped into a stress gradient parameter through a deformation and stress conversion model, and the aging bottleneck of a traditional method is broken through; according to the method, a double-track regulation and control mechanism driven by a delta sigma threshold value is constructed, medium and low stress regions are passivated and homogenized by means of cerium salt grain boundaries, a high stress region is subjected to targeted shape protection by means of a cerium salt and thiomalic acid composite film, dialectical unification of stress release priority and overall etching efficiency is achieved on the molecular level, and a scientific and efficient stress management and control mode is provided for copper alloy strip manufacturing.

This invention relates to the field of bionanomaterials technology, and particularly to mitochondrial-targeting nanomaterials capable of releasing HNO, their preparation methods, and applications. The preparation method of the mitochondrial-targeting nanomaterials capable of releasing HNO includes the following steps: synthesis of a silanized HNO donor: hydroxylamine hydrochloride is dissolved in a mixed solvent of anhydrous tetrahydrofuran and anhydrous pyridine, and a dichloromethane solution of 2-(4-chlorosulfonylphenyl)ethyltrimethoxysilane is added. The mixture is stirred at room temperature, and after post-treatment, a silanized HNO donor is obtained; synthesis of aminated carbon dots: chitosan, ethylenediamine, and mercaptosuccinic acid are dispersed in deionized water, and concentrated hydrochloric acid is added and stirred until dissolved. This preparation method can prepare mitochondrial-targeting nanomaterials capable of releasing HNO, achieving precise delivery, controlled release, and visual tracking of HNO to cardiac mitochondria, solving the technical problems of traditional HNO donors' inability to achieve stable loading on carriers and lack of mitochondrial targeting ability.

The present invention relates to a treatment process for reducing the sulfur content of calcined petroleum coke, and belongs to the technical field of petroleum coke desulfurization process. The treatment process comprises grinding the petroleum coke, screening it, adding a composite catalyst, mixing it, and then performing a high-temperature calcination treatment, which is completed after cooling; the preparation of the composite catalyst comprises: grinding and mixing rectorite, light calcium carbonate and anhydrous ethanol, adding mercaptosuccinic acid and stirring and mixing, adding a coupling agent and mixing it, and then heating it, filtering out the solid matter, vacuum drying and calcining it, adding ethylene glycol and deionized water and mixing it, adding nickel nitrate hexahydrate and ammonium molybdate tetrahydrate, adding ammonia water and heating and stirring it, cooling it to room temperature and then centrifuging it, washing it three times with an ethanol solution, vacuum drying it and then calcining it. The treatment process of the composite catalyst prepared by the present invention for catalyzing the desulfurization of petroleum coke has excellent desulfurization effect and can effectively reduce the sulfur content of calcined petroleum coke.

The invention discloses a visual detection method for fruit and vegetable pesticide residues based on a colorimetric array sensor of a smart phone. The preparation method comprises the following specific steps: (1) preparing six types of silver nanoparticles with multifunctional surfaces by taking AgNO3 as a silver source, PVP (Polyvinyl Pyrrolidone), CTAB (Cetyltrimethyl Ammonium Bromide), Tween 80, branched polyethyleneimine, thiomalic acid and L-cysteine as surface modifiers and NaBH4 as a reducing agent and adopting a chemical reduction method; (2) silver nanoparticles are combined with gelatin, and a silver nanoparticle hydrogel patch is prepared; and 3) integrating a smart phone, and constructing a silver nanoparticle colorimetric array intelligent sensor with 1 * 6 sensing element points for visual detection and distinguishing of various pesticide residues on the surfaces of fruits and vegetables. The detection limits of the sensor on cyromazine, chlorpyrifos, imidacloprid, dichlorvos, mancozeb and cartap are 4.9 mg / L, 0.99 mg / L, 0.49 mg / L, 2 mg / L, 3 mg / L and 0.3 mg / L respectively. The method disclosed by the invention has the characteristics of low cost, high sensitivity, strong selectivity, intelligence, portability and the like, and can be used for synchronously detecting and distinguishing various analytes.

This invention relates to a near-infrared low-potential electrochemiluminescence dual-ligand stabilized gold nanoclusters, their preparation method, and applications. The method uses chloroauric acid as the gold source and thiomalic acid and sodium citrate as reducing and stabilizing agents, respectively, in a two-step synthesis. First, Au is reduced online using thiomalic acid. 3+ Water-soluble gold nanoclusters were prepared using a novel method. These nanoclusters were then incubated with sodium citrate, and based on the ligand exchange principle, gold nanoclusters co-coated with thiomalic acid and sodium citrate were synthesized. The raw materials required for this invention are readily available and all possess good water solubility. The synthesis apparatus is simple, the conditions are mild, and the operation is safe. The resulting dual-ligand-coated gold nanoclusters exhibit good stability and produce low-potential near-infrared electrochemiluminescence in the long-wavelength region in an aqueous system. This overcomes the limitation of most current electrochemiluminescent materials requiring hydrazine hydrate or carbazide as a co-reactant. Using a non-toxic tert-butylamine-borane co-reactant, low-potential electrochemiluminescence radiation of 0.57V in the near-infrared region was generated.

The invention discloses an environment-friendly bio-based chinlon core-spun yarn and a preparation method thereof, and belongs to the technical field of bio-based high polymer materials and functional textile materials. The chinlon core-spun yarn comprises synergistically modified bio-based nylon-6, ellagic acid, an antioxidant, nano titanium dioxide, an antistatic agent and a lubricant; wherein the synergistically modified bio-based nylon-6 is a multi-network synergistically enhanced system formed by in-situ construction of a boron-oxygen heterocyclic structure, a dynamic sulfydryl exchange structure and an interface anchoring structure by bio-based nylon-6, phenylboronic acid, catechol, 2, 3-dimercaptosuccinic acid and gamma-aminopropyltriethoxysilane under a melting condition; the ellagic acid participates in the interchain multiple hydrogen bond and pi action through the rigid polyphenol conjugated structure of the ellagic acid, so that molecular-level synergistic regulation is realized. Under the condition of not increasing the load of the inorganic filler, the tensile strength and the thermal stability of the yarn are remarkably improved, the thermal shrinkage rate is reduced, the ultraviolet resistance and the thermo-oxidative aging durability are improved, and good environmental friendliness and industrial application prospects are achieved.

The present application relates to the technical field of in vitro diagnostic kit, especially to a carboxyl polystyrene microsphere and a preparation method thereof and application of the carboxyl polystyrene microsphere in a quantitative detection MxA kit, the preparation method of the carboxyl polystyrene microsphere is as follows: first, preparing polystyrene microspheres rich in aldehyde groups on the surface through a soap-free emulsion polymerization method; then, through Schiff base reaction, the surface of the microspheres is modified with 2-aminoethyl methacrylate hydrochloride, and meanwhile, the ester group and imino group can improve the hydrophilicity of the microspheres; finally, through a thiol-double bond addition reaction, the surface of the microspheres is generated with carboxyl-rich polystyrene microspheres through mercaptobutane dioic acid. The carboxyl polystyrene microsphere prepared by the present application can improve the binding efficiency of the latex and MxA antibody, thereby improving the detection sensitivity, and the purpose of high-sensitivity quantitative detection of MxA protein can be achieved, and the detection time is greatly shortened.

The invention relates to a nano prodrug as well as a preparation method and application thereof, and belongs to the technical field of nano preparations. Two nano prodrugs based on a hyperbranched polymer and an amphiphilic random copolymer are constructed, the hyperbranched polymer takes a mercaptosuccinic acid small molecule as a metal ion chelating agent, and a novel hyperbranched polymer which is rich in a thioacetal branched structure inside and is modified by mannose on the surface is constructed through sulfydryl-alkyne click chemistry and esterification. The amphiphilic random copolymer is prepared by carrying out reversible addition-fragmentation chain transfer polymerization on a functional chelating monomer (DSF) with ROS responsiveness and PEG (Polyethylene Glycol) with targeted group-mannose. The two nano prodrugs have the characteristics of inert circulation, macrophage precise targeting, pathological microenvironment dynamic response exposed copper chelation sites and the like, intracellular overloaded copper ions can be efficiently removed, the limitation of traditional symptomatic treatment is broken through, and a brand new strategy is provided for acute liver injury prevention and treatment.

The invention discloses a synergist in wastewater treatment and a preparation method thereof, and relates to the technical field of wastewater treatment. The nutritional agent comprises cassava starch derivatives, and the cassava starch derivatives are cassava starch esterification derivatives with the substitution degree of 0.18-0.19; in the cassava starch esterification derivative, a chemical structure for esterification grafting comprises a carboxylic acid compound; the carboxylic acid compound at least comprises mercaptosuccinic acid. The nutritional agent provided by the invention is easier to absorb by microorganisms, is applied to a wastewater treatment process to remarkably enhance the removal rate of COD and ammonia nitrogen in wastewater, can increase the total amount of beneficial bacteria in activated sludge, and is wide in application range.

The invention discloses a composite fluorescent visual sensor as well as a preparation method and application thereof, and relates to the technical field of analysis and detection. The composite fluorescent visual sensor is prepared by the following method: firstly synthesizing cadmium telluride quantum dots modified by mercaptosuccinic acid and cadmium telluride quantum dots modified by N-acetyl-L-cysteine, and then mixing a porphyrin stock solution with the cadmium telluride quantum dots modified by N-acetyl-L-cysteine to obtain a chiral nano porphyrin solution. And finally, mixing with a pre-synthesized mercaptosuccinic acid modified cadmium telluride quantum dot to prepare the composite fluorescent visual sensor. The prepared quantum dot-nano porphyrin composite fluorescent visual sensor has good selectivity on L / D-theanine, has high sensitivity and anti-interference performance, can be used for carrying out visual accurate analysis and application on the content of L / D-theanine, and has the advantages of simplicity in operation, high sensitivity, low cost and the like.

The application relates to a preparation method of a low-potential near-infrared electrochemiluminescence immunosensor taking t-butylamine-borane as a co-reagent. The application relates to a preparation of a low-potential near-infrared electrochemiluminescence (about 0.57 V vs Ag / AgCl) immunosensor, mainly including (1) a preparation method of water-soluble gold nanoclusters (Cit / MSA@Au NCs) capable of generating low-potential near-infrared electrochemiluminescence, taking double ligand citrate and thiomalic acid as stabilizers, (2) preparation of gold nanocluster-labeled secondary antibody (Cit / MSA@Au|Ab2), (3) preparation of a low-potential near-infrared electrochemiluminescence sensor based on a sandwich immunization principle and taking gold nanoclusters as a label, and (4) drawing of a working curve. The prepared low-potential near-infrared electrochemiluminescence immunosensor has high detection sensitivity, and other antigen proteins do not interfere with the sensing and detection of the target antigen of the application.

The application discloses a high-selectivity copper-lead separation combined inhibitor and application thereof, and belongs to the technical field of mineral processing and non-ferrous metal flotation. The components of the combined inhibitor include sodium periodate and mercaptosuccinic acid, and the mass ratio of the sodium periodate to the mercaptosuccinic acid is 1:3-1:7. The combined inhibitor is composed of the sodium periodate and the mercaptosuccinic acid, is used in the process of separating copper and lead from a lead sulfide ore, and is used for accurately and effectively inhibiting galena, thereby reducing the influence of the combined inhibitor on chalcopyrite flotation, and finally making the lead sulfide ore have excellent flotation separation effect and obtaining high-grade copper and lead concentrates.

The application discloses a nutrient agent in biochemical treatment of organic wastewater and a preparation method thereof, and relates to the technical field of wastewater treatment. The nutrient agent comprises cassava starch derivatives, and the cassava starch derivatives are esterification derivatives of cassava starch with a substitution degree of 0.18-0.19; in the esterification derivatives, the chemical structure for esterification grafting comprises carboxylic acid compounds; and the carboxylic acid compounds at least comprise mercaptobutane dicarboxylic acid. The nutrient agent is more easily absorbed by microorganisms, the removal rates of COD and ammonia nitrogen in wastewater are obviously increased when the nutrient agent is applied to a wastewater treatment process, the total amount of beneficial bacteria in active sludge can be increased, and the application range is wide.

The invention relates to a glycosylated luminous gold nanomaterial as well as a preparation method and application thereof. The preparation method comprises the following steps: performing in-situ reduction on chloroauric acid by taking thiomalic acid (MSA) as a protective agent to obtain a gold nano-cluster of which the gold core particle size is about 1.8 nm; and activating carboxyl on the surface of the gold nano-cluster (GlcN-MSA-AuNPs) by EDC / NHS, and coupling with glucosamine to obtain the glucosamine-modified gold nano-cluster (GlcN-MSA-AuNPs). The nano material can generate stable fluorescence in a near-infrared region I (about 786 nm) under the excitation of 600 nm, can effectively reduce normal tissue accumulation and non-specific adsorption, and has good biocompatibility and tumor active targeting property. The nano material prepared by the invention can be used for rapid detection and near-infrared imaging of subcutaneous transplanted tumors of small animals.

The invention provides a cyanide-free cupronickel-tin electroplating solution and an electroplating method, and relates to the technical field of electroplating. The cyanide-free cupronickel tin electroplating solution comprises the following components: 20 to 50 g / L of copper sulfate, 10 to 30 g / L of stannous mono-sulphate, 90 to 110 g / L of sulfuric acid, 90 to 120 g / L of 3-mercapto-1-sodium propane sulfonate, 50 to 80 g / L of ammonium citrate, 10 to 20 g / L of carboxyethyl thiosuccinic acid, 0.02 to 0.05 g / L of polyepoxysuccinic acid, 0.1 to 0.3 g / L of thiomalic acid, 0.2 to 0.5 g / L of polyaspartic acid, 2 to 4 mL / L of PEG-5 disodium lauryl citrate sulfosuccinate and 1 to 2 mL / L of L-64 propylene glycol block polyether. By adding ammonium citrate, the plating solution can be clarified, by using carboxyethyl thiosuccinic acid, a plating layer can be finer, by using polyepoxysuccinic acid, plating solution precipitation and plating layer impurities can be reduced, by using the dispersion effect of L-64 propylene glycol block polyether, the surface tension is reduced, the plating layer is more uniform and smoother, and wetting of the plating solution on a complex workpiece is promoted.

The invention discloses a method for prolonging the shelf life of a perovskite precursor solution, and relates to a method for improving the storage stability of the perovskite precursor solution by adding succinic acid or a derivative thereof (such as mercaptosuccinic acid) into the perovskite precursor solution. According to the method, the additive interacts with Pb < 2 + > or halide ions in the precursor, so that the problems of component degradation, precipitation and the like are inhibited, and the shelf life of the precursor solution in air and thermal environments is prolonged. A thermal aging experiment and absorption spectrum contrastive analysis show that a succinic acid derivative sample still has good solution transparency and film-forming ability after being stored for 7 days. The method is suitable for controlling the long-term stability of the precursor solution in the production of perovskite photovoltaic devices.

The application provides a copper plating solution and a stabilizer, which comprises copper sulfate pentahydrate, a complexing agent, formaldehyde, ethanolamine, 2,2-bipyridine, S-adenosyl-L-homocysteine, S-carboxymethyl-L-cysteine and thiomalic acid. The S-adenosyl-L-homocysteine and the S-carboxymethyl-L-cysteine can improve the tolerance of the plating solution to leached palladium. After a certain amount of thiomalic acid is added, the three components have a good synergistic effect. The plating solution maintains high activity and further improves the tolerance to leached palladium, which is beneficial to improve the service life of the plating solution and prolong the decomposition time of the plating solution. Even under high leached palladium concentration, the thick copper solution does not affect the plating activity and the uniform plating capacity of the chemical copper plating solution. Under normal production load, a deposition rate of 1.0 um / 20 min can be obtained. The solution has good stability. Under extreme conditions of high leached palladium, the decomposition time of the plating solution is prolonged by 2-6 hours.

The invention relates to the technical field of batteries, in particular to an alkaline aluminum-air battery electrolyte and a preparation method thereof and an alkaline aluminum-air battery, the alkaline aluminum-air battery electrolyte comprises an additive and an alkaline solution, the additive is mercaptosuccinic acid, the mass percentage of the additive is 0.01-10%, and the molar concentration of the alkaline solution is 0.1-10 mol / L. The additive mercaptosuccinic acid can be preferentially adsorbed on the metal surface, the self-corrosion and hydrogen precipitation of an aluminum anode are remarkably inhibited, and meanwhile, the distribution of discharge products is optimized, so that the high energy density of the aluminum air battery is realized, the electrochemical performance of the aluminum air battery is improved, the anode utilization rate is improved, and the anode utilization rate is up to 78.1%. The electrolyte and the additive thereof provided by the invention are simple in component composition, low in cost and safe and meet the environmental protection requirement, and use of rare heavy metal ions and harmful substances is avoided.

This invention discloses an inverse perovskite anode interface modification material and its application, belonging to the field of perovskite solar cell technology. The interface modification material includes thiomalic acid, 2-amino-3-sulfonylpropionic acid, DL-2-amino-3-phosphopropionic acid, dimercaptosuccinic acid, etc. The interface modification material contains two or more groups that interact with TCO (total organic carbon), and the material preferentially and directionally deposits in areas not covered by SAM (soil anode metallization layer). During the deposition process of this interface modification material, an alcohol-soluble solvent can partially dissolve and wash away aggregated SAM molecules, improving the coverage of SAM molecules and enhancing the hole extraction and transport capabilities of the SAM hole transport layer. The interface modification material of this invention contains groups that interact with perovskite, reducing the formation of cracks and pores at the perovskite buried interface, and reducing and passivating defects.

The invention provides a gold salt, a purification method of the gold salt, a cyanide-free electroplating solution and a preparation method and a use method of the cyanide-free electroplating solution. The cyanide-free electroplating solution mainly comprises the gold salt purified through the purification method in the embodiment of the invention and conductive salt. According to the purification method in the embodiment of the invention, firstly, sodium gold mercaptosuccinate with the gold content of 35-49.51 w / % is dissolved in hot pure water at the temperature of 60-80 DEG C, and a sodium gold mercaptosuccinate solution is obtained; dropwise adding the gold sodium mercaptosuccinate solution into a water-insoluble weak-polarity organic solvent to obtain a mixed solution; stirring the mixed solution, and purifying the mixed solution after stirring to obtain purified gold salt; the gold content of the gold salt is 55.01-56.9 w / %, the total impurity content is less than 0.01%, and the single impurity content is less than 5PPM. The gold salt obtained through the purification method is high in gold content and low in impurity content, the electroplating liquid prepared by taking the gold salt as the cyanide-free electroplating raw material is high in stability and long in service life, and the obtained gold-plated layer is good in quality.

The invention relates to the technical field of nano materials, and discloses a nano preparation as well as a preparation method and application thereof. The nano preparation contains a phospholipid compound, an inhibitor A and an inhibitor B, the inhibitor A is selected from at least one of rapamycin, fluconazole, amphotericin B and caspofungin, and the inhibitor B is selected from at least one of deferasirox, deferoxamine, deferoxone, dimercaptosuccinic acid and penicillamine. The nano preparation has a good bacteriostatic and bactericidal effect on biphasic fungi, has a good treatment effect on systemic infection, and can weaken the toxic and side effects of drugs.

The invention discloses an Au-Cu-coated MSA nanocluster and a preparation method and application thereof.The preparation method comprises the following steps that 1, chloroauric acid serves as a gold source and is dissolved and stirred in a solvent, thiomalic acid is added, and the color of the solution is changed from yellow to faint yellow until the solution is colorless; (2) continuously adding copper chloride as a copper source to change the color of the solution from colorless to faint yellow, continuously adding a sodium borohydride aqueous solution, and isolating air to change the color of the solution to black; and (3) adding a methanol aqueous solution, washing to obtain a black precipitate, and drying at room temperature to obtain the Au-Cu MSA nanocluster. The Au-Cu-coated MSA NCs disclosed by the invention shows excellent peroxidase-like and glutathione catalase-like activity, and a synergistic treatment effect is realized by cascade catalytic treatment and promotion of wound healing; synergistic antibacterial, anti-inflammatory and regeneration effects are achieved, and a powerful platform is provided for effective diabetes wound treatment.

The purpose of the present invention is to provide a novel cocrystal of Amenamevir having excellent solubility.　The present invention provides a cocrystal comprising Amenamevir and a coformer, in which the coformer is one or more selected from the group consisting of succinic acid, L-malic acid, D-malic acid, L-tartaric acid, D-tartaric acid, fumaric acid, maleic acid, phenol, salicylic acid, D-camphor, 1-naphthol, 2-naphthol, benzotriazole, vanillin, anthranilic acid, thiomalic acid, pyrogallol, hydroquinone lidocaine, chlorocresol, chlorobutanol, catechol, resorcinol, o-cresol, m-cresol, p-cresol, 1,2,4-trihydroxybenzene, 1,3,5-trihydroxybenzene, and 4-methylcatechol.

The invention relates to a keratin-based nitric oxide donor as well as a preparation method and application thereof. The preparation method of the keratin-based nitric oxide donor comprises the following steps: S1, reacting activated thiomalic acid with keratin to obtain a conjugate; s2, the conjugate obtained in the step S1 reacts with tert-butyl nitrite, and the keratin-based nitric oxide donor is obtained. The method provided by the invention is simple to operate and mild in condition, and the obtained NO donor is higher in NO loading capacity, more in release amount and long-acting.

The present application belongs to the field of chemical analysis test, and particularly relates to a coumarin fluorescent probe based on aminobenzaldehyde for preparing a reagent for detecting mercaptosuccinic acid and a preparation method. 2-Aminobenzaldehyde and 7-(diethylamino)coumarin-3-carboxylic acid are dissolved in dichloromethane, 1-ethyl-(3-dimethylaminoaldehyde) carbonyldiimidazole hydrochloride (EDCI) and 1-hydroxybenzotriazole (HBOT) are added as condensing agents, and the reaction is stirred at room temperature. The obtained crude product is separated and purified by thin layer chromatography to obtain the final yellow product, the coumarin fluorescent probe Y-SH based on aminobenzaldehyde. The coumarin fluorescent probe prepared by the present application can rapidly detect mercaptosuccinic acid in deionized water.

The invention relates to the technical field of agent preparation, in particular to a beneficiation agent containing stearic acid and a preparation method of the beneficiation agent, and the agent comprises the following components in percentage by mass: 40-65% of stearic acid, 10-30% of oleic acid, 5-15% of mercaptosuccinic acid, 3-8% of nonionic surfactant polyoxyethylene sorbitan monooleate and 10-25% of organic solvent diethylene glycol monobutyl ether. By accurately controlling the mass ratio of stearic acid to oleic acid (1.5: 1-4: 1) and introducing polyoxyethylene sorbitan monooleate, the invention is kept in a complete liquid state in low-temperature ore pulp at 5-15 DEG C, no crystal is separated out after standing for 24 hours, the applicable temperature lower limit is reduced by more than 10 DEG C compared with the traditional stearic acid medicament, and the product quality is greatly improved. Therefore, pipeline blockage and effective component loss are avoided, and annual continuous production in alpine regions is guaranteed.

The present application relates to the preparation method and application of the complex of the engineered bacteria loaded with the functionalized melanin nanosystem, which can effectively solve the problems of activating the STING pathway, reversing T cell exhaustion, improving the effect of tumor immunotherapy and ensuring the effect of cancer treatment drugs, and the melanin is prepared into melanin nanoparticles, and the carboxylated melanin nanoparticles are formed through the thiomalic acid reaction, the polypeptide chain and 2-cyano-6-amino-benzothiazole are modified at the carboxyl terminal of the melanin nanoparticles through the amidation reaction, the metal ions are complexed on the surface of the functionalized melanin nanoparticles through the metal complexation, and finally the functionalized melanin nanosystem is adhered to the surface of the engineered escherichia coli through the adhesion, so as to obtain the complex of the engineered bacteria loaded with the functionalized melanin nanosystem; the present application is convenient to operate, the method is stable and reliable, has good biocompatibility and long retention time, can play the multiple effects of targeting tumor, activating the cGAS-STING pathway, blocking the PD-1 / PD-L1 axis and reversing T cell exhaustion.