84 results about "Redox responsive" patented technology

The invention relates to a method for preparing a stable albumin nanoparticle, and belongs to the technical field of preparation of biomedical materials. The method comprises the following steps: pretreating albumin by using glutathione and cysteine without biotoxicity; opening an intramolecular disulfide bond; precipitating the albumin by using anti-solvents such as alcohol and the like; and carrying out exchange reaction on a sulfydryl-disulfide bond to obtain the albumin nanoparticle containing the intramolecular disulfide bond. The prepared albumin nanoparticle can be used for the delivery of pharmacological active substances and / or diagnostic agents in an organism. The albumin nanoparticle provided by the invention has the advantages that the albumin nanoparticle has good stability under a dilution condition and gives an oxidation reduction response in a reduced environment. Based on the characteristics, the albumin nanoparticle can stably exist in a blood circulation system of the organism, and can carry out a degradation reaction in a cell under the action of reduced glutathione so as to release a wrapped medicine.

The invention provides a nanogel with hydrophilic and hydrophobic reversal, charge reversal and intracellular redox responsiveness on the basis of pH regulation. The nanogel is prepared by cross-linking of thermo-sensitive monomer with controllable radical polymerization, amphoteric ionic monomer and amido-containing pH sensitive monomer through a disulfide-bond-containing cross-linking agent. The invention further provides a nanogel drug carrier system with smart response to tumor microenvironment and its preparation method. On the condition of blood pH 7.4, the nanogel is in a hydrophilic swelling state that is favorable for avoiding being phagocytosed by the reticuloendothelial system (RES) and accordingly, the nanogel has blood long circulation capacity; on the condition of tumor tissue subacidity, the state of the nanogel is reversed into a hydrophobic shrinking state that is favorable for the nanogel to realize effective concentration, depth penetration and be absorbed effectively by tumor cells on the tumor location. Besides, in the intracellular lysosome environment, negative charge of the nanogel is reversed into positive charge, which is favorable for the nanogel to escape from the lysosome; and then the nanogel releases drugs responsively in cytoplasm high-GSH environment, thereby achieving a good tumor inhibition effect.

The invention discloses a method for preparing stable albumin nano-particles, belonging to the technical field of biological medicine material preparation. The method comprises the following steps of: carrying out pretreatment on albumin by utilizing non-biotoxic glutathione or cysteine to open intramolecular dithio bonds, precipitating the albumin by using anti-solvents such as alcohol and the like, and carrying out sulfydryl-dithio bond exchange reaction so as to obtain albumin nano-particles with intermolecular dithio bonds. The prepared nano-particles can be used for delivering in-vivo pharmacologically active substances and / or diagnosis aids. The obtained albumin nano-particles have the advantages that the albumin nano-particles not only have good stability under dilution condition, but also have oxidation reduction response in a reduction type environment; and due to such characteristics, the particles can stably exist in in-vivo blood circulation systems of organisms and are degraded under the action of reduced glutathione so as to release the wrapped medicine.

The invention belongs to the field of preparation of biological medical materials, and relates to a method for preparing stable albumin nano-particles by virtue of thermal denaturation. The method comprises the following steps: (1) adding vanillic aldehyde or an analogue thereof to form intermolecular disulfide bonds by virtue of inter-reaction of free sulfhydryl groups on albumin molecules under a heating condition; (2) enabling amino groups inside and among molecules to react with carboxyl so as to form amido bonds; and (3) enabling amino groups on the albumin molecules to react with aldehyde groups on vanillic aldehyde or the analogue thereof to form chemical bonds of Schiff base and the like so as to form stable nano-particles in an aqueous solution. Any organic solvent is not introduced during preparation, so that the prepared nano-particles are safe and nontoxic, and can well entrap antitumor drugs including paclitaxel, doxorubicin hydrochloride and the like. Moreover, the carrier has an oxidation reduction response in a tumor cell internal environment, and can open disulfide bonds to release drugs under the action of reducing glutathione in cells. The method provided by the invention is simple in process, convenient to operate and suitable for industrial mass production.

The invention relates to mercapto-carboxyl dual-modified mesoporous silica nanoparticles and a preparation method therefor and belongs to the technical field of medicines. The preparation method for the mercapto-carboxyl dual-modified mesoporous silica nanoparticles comprises the steps: (1) preparing mercaptopropyl modified mesoporous silica nanoparticles; and (2) preparing the mercapto-carboxyl dual-modified mesoporous silica nanoparticles. The product has the mean particle size of 50nm to 200nm. Through mercapto modification, covalent drug loading can be carried out, a mesoporous silica drug loading system with oxidation-reduction response is prepared, and the release of drugs is effectively controlled; and through a carboxyl charge action, the drug loading capacity of alkalescent drugs can be improved, the release speed is high in case of small pH, and the toxic or side effects on normal tissue caused by the drugs can be lowered, so that the product has a broad application prospect.

The invention relates to a Cu(I) metal gel and chitosan composite magnetic microsphere adsorption agent with good acid resistance and oxido-reduction responsiveness as well as a preparation method and application of the adsorption agent. The method comprises the following steps: (1), preparing Cu(I)-2-mercapto benzimidazole (Cu(I)-2-MBIm) metal gel powder; (2), preparing single-coated magnetic SiO2 nano-particles; (3), preparing the magnetic SiO2 nano-particle and Cu(I)-2-MBIm gel powder coated chitosan microsphere. The preparation method provided by the invention is simple in process and mild in condition and is very suitable for large-scale commercialized production; besides, prepared magnetic composite not only has good acid resistance. but also has good detoxicating and removing property to Cr(VI) ions; the used adsorption agent can be effectively regenerated by an ascorbic acid solution very easily.

The invention discloses a pH / redox double responsive glucan hydrogel and a preparation method thereof and belongs to the technical field of biomedical functional high molecular materials. The preparation method comprises the following steps: preparing formylated glucan by oxidizing sodium periodate with sodium periodate; dissolving glucan in deionized water to prepare an aqueous solution of certain concentration; adding a crosslinking agent containing amino and disulfide bonds into the aqueous solution at the same time; and adjusting the pH value of the solution to be alkaline and carrying outa crosslinking reaction to obtain the glucan hydrogel. The degrading behavior of the glucan hydrogel prepared by the method has certain pH and redox responsiveness. The preparation method is simple and mild in implementing condition. The obtained glucan hydrogel structure contains Schiff base bonds and disulfide bonds, has pH / redox double responsiveness, and can be applied to the field of biomaterials as an environment responsive drug carrier.

The invention discloses a preparation method of an oxidoreduction responsiveness tumor-targeted cis-platinum nanometer drug delivery system, and application thereof, relates to the building and the preparing of a high-load cis-platinum macromolecule pro-drug and a hyaluronic acid-coated high-load cis-platinum nanometer drug delivery system, and can be applied to active targeting treatment of tumors. Polyethyleneimine is adopted as a framework, and cystamine containing a disulfide bond with oxidoreduction responsiveness is selected to be reacted with butanedioic anhydride so as to be complexedwith cis-platinum, so that a cis-platinum complex is obtained. The obtained cis-platinum complex and the polyethyleneimine are covalently bonded to obtain the high-load cis-platinum macromolecule pro-drug, and a hyaluronic acid targeted group is coated on an outer layer, so that the oxidoreduction responsiveness tumor-targeted cis-platinum nanometer drug delivery system with a tumor active targeting function is obtained. Compared with traditional chemotherapy drug cis-platinum, the oxidoreduction responsiveness tumor-targeted cis-platinum nanometer drug delivery system provided by the invention can realize tumor active targeting drug delivery and oxidoreduction responsiveness drug release, plays a role in anti-tumor treatment, is capable of effectively reducing the toxic and side effects caused by the cis-platinum on other visceral organs of a body, and has a favorable clinic application prospect.

The invention relates to an oxidized-graphene nano-drug carrier with a targeting function. The oxidized-graphene nano-drug carrier comprises oxidized-graphene, PyBA PEG FA and PyBA S S Drug. The invention further provides a preparing method of the oxidized-graphene nano-drug carrier, and the preparing method comprises the steps of firstly using polyethylene glycol with dual-amidogens be subjected to coupled reactions with folic acid and pyrene-1-butyric acid respectively to prepare PyBA PEG FA, conducting a reaction among pyrene-1-butyric acid and cystine and adriamycin amycin to prepare PyBA S S Drug, then mixing oxidized-graphene, PyBA PEG FA and PyBA S S Drug according to a certain proportion, conducting stirring and time treatment to some degree to obtain a nano-drug carrier solution with a certain concentration. The preparing method of the oxidized-graphene nano-drug carrier is simple in technology, and the obtained nano-drug carrier has high drug-carrying efficiency, and has a redox-responsive property and targeting property; meanwhile, various kinds of materials used for preparing the carrier have good biocompatibility.

The invention discloses a carbon nanotube grafted ferrocene polymer nano composite electrochemical sensing material inlaid with gold and a preparation method and an application thereof. The sensing material is composed of a carbon nanotube with excellent electrochemical property, gold nanoparticles and polyferrocene ethyl formyl methacrylate with redox response. The preparation process relates tomodification, complexing and esterification of the gold nanoparticles on the surface of the carbon nanotube and grafting of a ferrocenyl polymer to the surface of the carbon nanotube inlaid with goldthrough atom transfer radical polymerization. The sensing material can be used as an electrode modification material; an electrochemical sensing film which is excellent in electrochemical property, good in electrochemical sensitivity, reversibility, repeatability, wide linear range and low detection limit can be obtained by regulating the system composition and the grafting rate. The electrode modification material can be used for simple, quick, accurate, effective and reliable food safety detection.

The invention discloses shape memory hydrogel with calcium ion complexing and oxidation reduction dual response and a preparation method of the shape memory hydrogel. The preparation method comprisesthe following steps that 6-30 weight parts of polysaccharide containing sulfydryl, 12-30 weight parts of hydrophilic thermoplastic macromolecules, 0.12-5 weight parts of acrylic ester, and 0.01-0.08 weight part of an initiator are dissolved in 50-80 parts of water, the initiator causes unsaturated bonds on the acrylic ester to have polymerization reaction, change-temperature treatment is carried on the polymerization product at the temperature range of -18 DEG C to 60 DEG C, and thus the shape memory hydrogel is obtained. The hydrogel has the calcium ion response shape memory performance, theoxidation reduction response shape memory performance, and the procedural dual response shape memory performance of the two, has good shape memory performance, is mild in response condition, is good in biocompatibility, and has wide application prospect in the aspects of bioengineering and the like.

The invention discloses a cross-linked nano-micelle with redox sensitive performance and a preparation method of the cross-linked nano-micelle. The preparation method comprises the following steps: a reversible addition-fragmentation chain transfer polymerization method is adopted, a macromolecular chain transfer agent is synthesized firstly and polymerized with poly(ethylene glycol) methacrylate to synthesize a block polymer which can be further modified, on the basis of self-assembly, a cross-linking agent having chemical linking capacity and containing a disulfide bond is introduced, and one stably cross-linked nano-micelle with the redox response performance is constructed in a mode of assembly and later cross-linking. The method is easy to control, the reaction conditions are mild, a metal catalyst is avoided, a product is easy to purify, and the obtained nano-micelle not only can package a hydrophobic drug but also can prevent the drug from being released in advance in blood circulation.

The invention discloses a preparation method of a soil stabilizing agent. The method includes: (1) dissolving sodium carboxymethylcellulose in a water solution to prepare a sodium carboxymethylcellulose water solution, and regulating the pH value thereof; (2) dissolving 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and N-hydroxysuccinimide in the sodium carboxymethylcellulose water solution, adding a dithio bis-functional group crosslinker, stirring the mixture and allowing the mixture to stand for forming hydrogel, and freeze-drying the hydrogel to obtain the soil stabilizing agent. By means of the natural polymer, sodium carboxymethylcellulose, being a base material, the hydrogel having redox responsibility is prepared through a crosslinking reaction. When being applied tosoil, the soil stabilizing agent is reacted with reductive substances in the soil to damage the crosslinking structure, so that cellulose structure can be combined with heavy metal ions in the soil through the thiol functional groups on the surface, thus reducing bioavailability and mobility of the heavy metal ions.

The invention belongs to the technical field of biological medicine, and discloses a novel albumin-siRNA composite nanometer particle, and a preparation method and applications thereof. According to the preparation, the internal space structure of albumin is destroyed using a disulfide bond reducing agent, and proteins containing mercapto group active groups are obtained, siRNA and / or a modified substance SH-siRNA is added, and a selenium compound is added so as to obtain the novel albumin-siRNA composite nanometer particle. The preparation method is simple; the nanometer size is uniform at different dilution concentrations, the dispersion performance is excellent, the stability in artificial gastric juice, intestinal juice, and blood environment is excellent; and in addition, the novel albumin-siRNA composite nanometer particle possesses intracellular reduced glutathione microenvironment responsiveness; the novel albumin-siRNA composite nanometer particle possesses oral administrationand injection administration living tumor targeting characteristic, is capable of increasing siRNA anti-cancer drug oral administration or injection administration anti-cancer activity, and reducingtoxic or side effect.

The invention provides a preparation method and a purpose of oxidation-reduction response chitosan-lipidosome. The method is characterized in that disulfide disuccinimidyl substituted ester is used for synthesizing oxidation-reduction response disulfide bond connected double-aliphatic-chain substituent group phosphatidyl ethanolamine-s-s-chitosan. The synthesized double-aliphatic-chain substituent group phosphatidyl ethanolamine chitosan is used for modifying lipidosome by a back insertion self assembly method; the double-aliphatic-chain substituent group phosphatidyl ethanolamine chitosan-lipidosome medicine carrier with oxidation-reduction response chitosan brushes on the surface is formed through assembly. The assembled chitosan-lipidosome has strong cell adhesion performance and antiserum capability, has the environment response performance at the same time, and is applicable to intravenous injection. The invention also provides application of superparamagnetic ferroferric oxide nanometer particles coated by the chitosan-lipidosome to medicine delivery. High medicine delivery efficiency and high biocompatibility are realized; wide application prospects are realized.

The invention discloses a multi-functional liposome having oxidation-reduction responsiveness and capable of reinforcing tissue permeation, and a preparation method and application of the multi-functional liposome. A disulfide bond mediated oxidation-reduction responsiveness DSPE-S-S-chemotherapeutic drug prodrug is modified on the surface of the liposome, a hydrophobic photosensitizer is loaded on a phospholipid bimolecular layer, and a hydrophilic drug capable of reinforcing tissue permeability is entrapped in a water phase in the liposome. The liposome prepared by the preparation method disclosed by the invention can release chemotherapeutic drugs in a manner of oxidation-reduction responsiveness, permeation of the liposome in tumor tissue and infiltration of the liposome in peripheraloxygen are reinforced, the liposome can be used as a pharmaceutical preparation capable of resisting breast cancer, resisting liver cancer, resisting lung cancer or resisting cervical cancer for treating tumors, and the effect of synergistically resisting the tumor with chemotherapy / photodynamic therapy is increased.

The invention discloses a redox responsive amphiphilic copolymer as well as a preparation method and application of the redox responsive amphiphilic copolymer. The redox responsive amphiphilic copolymer is a compound with the structure of the formula I, wherein X is an antitumor active drug with carboxyl groups or carboxyl groups after derivatization of acetic anhydride. The redox responsive amphiphilic copolymer can be self-assembled to form micelles in water, hydrophobic ends of the inner layers of the micelles are encapsulated with hydrophobic antitumor drugs Y, and the micelles can further load treating genes Z by electrostatic interaction to obtain the micelles which simultaneously load therapeutic genes and chemotherapeutic drugs. The redox responsive amphiphilic copolymer and the micelles formed by self-assembling of the redox responsive amphiphilic copolymer and the micelles which simultaneously load the therapeutic genes and the chemotherapeutic drugs all can be used for preparing the antitumor drugs; furthermore, the redox responsive amphiphilic copolymer is simple in preparation method, does not need special equipment or harsh conditions, is easy to realize large-scale production and has very strong practical values.

The invention discloses hydrogel with multiple response function and a preparation method and application thereof; the preparation method of the hydrogel comprises the steps of adding hydrogel material, acryloyl chloride and triethylamine into a solvent, and reacting under ice bath to obtain modified hydrogel material; adding diselenide-diol, acryloyl chloride and triethylamine into a solvent, reacting under ice bath to obtain modified diselenide with C-C double bond; mixing the modified hydrogel material solution with the modified diselenide solution, adding a photo-polymerization initiator, and irradiating in ultraviolet at 20-40 DEG C to generate hydrogel having multiple response function. The hydrogel material is responsive to temperature, light and redox, quick gelling can be achieved by adjusting temperature, bulk concentration, photo-polymerization initiator concentration and a light source, the hydrogel is easy to form and has excellent mechanical properties and biocompatibility, and redox responsiveness of the hydrogel helps load different drug molecules and release them effectively.

The invention belongs to the technical field of organosilicone hybrid materials, and discloses a redox-response microsphere and preparing and degradation methods. The preparing method includes the steps that octavinyl-polyhedral oligomeric silsesquioxane, elemental sulfur / alicyclic olefin copolymer and a stabilizer are dissolved in an organic solvent to form an organic phase; a surfactant is dissolved in water to form a water phase; the organic phase and the water phase are mixed and emulsified, and emulsion is obtained; the obtained emulsion is reacted under the stirring and uv-irradiation conditions, a product is dried, and the redox-response microsphere is obtained. The redox-response microsphere and 30% by weight of a H2O2 solution are dispersed in water and stirred, and degradation ofthe redox-response microsphere is completed. According to the redox-response microsphere and the preparing and degradation methods, the microsphere is obtained in a polymerization mode with a photo-initiation miniemulsion mercaptan-alkene clicking method, and the microsphere prepared with the method has the advantages of being even in distribution, free of by-product and free of radical initiator, and is degradable, environmentally friendly and harmless.

The invention aims at solving the technical problem of providing a preparation method of a reduction response type nano material for coating and loading an antitumor drug. An HNTs (Halloysite Nanotubes)-polymer nano composite material is formed through carrying out covalent modification on the surfaces of HNTs by using a silane coupling agent and connecting up a disulfide bond containing nanotubewith an amino group at a terminal and meanwhile, through the electrostatic interaction between the amino group at the terminal of the nanotube and a carboxyl group at the terminal of a block copolymerPEO-b-PAA (Polyethylene Oxide-b-Polyacrylic Acid). The reduction response type nano material can be used for a carrier of the antitumor drug by adding a redox-response radical disulfide bond during design, and meanwhile, realizes enabling a the drug carrier to be capable of maintaining long-range circulation in vivo and to quickly release a drug at a diseased region. The stable cross-linked structure of the micelle of a polymer can be used for improving the stability of the micelle, and can be used for enhancing the stability of the drug when serving as the drug carrier; the micelle based onthe disulfide bond can be used for achieving the release, at a tumor region, of the drug, and the treatment effect is improved.

The invention discloses a high-sensitivity oxidation-reduction responded self-repairing anticorrosive coating and belongs to the technical field of metal anticorrosive coatings. The high-sensitivity oxidation-reduction responded self-repairing anticorrosive coating is prepared from an organic-inorganic hybrid sol-gel coating and a magnetic intelligent nano container doped into the organic-inorganic hybrid sol-gel coating. A preparation process comprises the following steps: preparing the magnetic intelligent nano container; dispersing the magnetic intelligent nano container into organic-inorganic hybrid sol-gel; coating the surface of a magnesium alloy substrate with a mixture to form the high-sensitivity oxidation-reduction responded self-repairing anticorrosive coating. By adopting the high-sensitivity oxidation-reduction responded self-repairing anticorrosive coating provided by the invention, the dense degree of a coating substrate can be improved, and corrosion inhibitor molecules can be actively and rapidly released when the coating is damaged and a metal substrate is exposed in a corrosive environment and the corrosion inhibitor molecules are adsorbed on the surface of the metal substrate to realize a self-repairing effect; the high-sensitivity oxidation-reduction responded self-repairing anticorrosive coating is an anticorrosive coating with good performances and application potential.

The invention belongs to the field of functional materials, and more particularly relates to a redox-responsive color-changing rare earth supramolecular gel fluorescent material and a preparation method thereof. The redox-responsive color-changing rare earth supramolecular gel fluorescent material is prepared by mixing a mixed solution of an aqueous solution containing rare earth ion europium ionsand alkali liquor with an organic solution containing gel factor 3,5-dinitrosalicylic acid. Under alkaline conditions, the rare earth supramolecular gel fluorescent material is self-assembled by utilizing the coordination effect of the gel factor 3,5-dinitrosalicylic acid and rare earth ion europium ions and the PI-PI interaction of benzene rings of the 3,5-dinitrosalicylic acid. The gel formed has unique fluorescence characteristics of the rare earth ions, good luminous intensity and high fluorescence efficiency, and the excitation spectrum is located in a visible light region and has stronganti-interference capability. The rare earth supramolecular gel has redox responsiveness, simple and rapid preparation process, no need of heating treatment, and easily available gel factor, and therare earth supramolecular gel material has better application prospect in the high-end anti-counterfeiting field.

The present invention provides a preparation method of a redox-responsive chitosan-liposome and use thereof, wherein the method uses dithiobis succinimidyl-substituted ester to synthesize a redox-responsive and disulphide bonded double fatty chain substituent phosphatidylethanolamine-s-s-chitosan. Using the synthesized double fatty chain substituent phosphatidylethanolamine chitosan, by a post-insertion and self-assembly method, to modify liposome, to construct a double fatty chain substituent phosphatidylethanolamine chitosan-liposome drug carrier having a redox-responsive chitosan brush on the surface thereof. The chitosan-liposome constructed in the present invention not only has the strong cell adhesion property and the antiserum property, but also has environmental response properties, being suitable for the intravenous injection. The present invention also provides the use of the chitosan-liposome encapsulating super-paramagnetic ferroferric oxide nanoparticles in drug delivery, which has high drug delivery efficiency and high biocompatibility, and has broad application prospects.

The invention discloses a preparation method and application of a tumor microenvironment and redox step-by-step responsive nano drug delivery system, and relates to preparation of a high-load cis-platinum polymer prodrug and a double-terminal aldehyde polyethylene glycol cross-linked cis-platinum nano drug delivery system, and can be used for tumor treatment. According to the invention, polyethyleneimine serves as a framework; cystamine containing redox responsive disulfide bonds is selected to react with succinic anhydride and then complexed with cis-platinum to acquire a cis-platinum complex; the acquired cis-platinum complex is covalently bound with polyethyleneimine to acquire the high-load cis-platinum polymer prodrug, and the outer layer is crosslinked by adopting double-terminal aldehyde polyethylene glycol to acquire the cis-platinum nano drug delivery system with tumor microenvironment and redox step-by-step responsiveness; compared with traditional chemotherapeutic drug cis-platinum, the cis-platinum drug delivery system provided by the invention has the advantages that polyethylene glycol shell removal and intracellular redox step-by-step responsive drug release in an extracellular microenvironment of tumors can be realized, and effective uptake of the cis-platinum drug delivery system and responsive release of drugs in tumors are ensured; the antitumor effect of thecis-platinum drug delivery system is better exerted; and the cis-platinum drug delivery system has a good clinical treatment application prospect.

The invention provides a preparation method of a quaternary ammonium salt-type antibacterial coating allowing stimulating responsive medicine releasing. The coating not only has excellent antibacterial effect but also achieves responsive releasing of a medicine for therapy. The preparation method of the coating includes the steps of: preparing a polymer, poly-1-bromododecyl dimethylaminoethyl methacrylate quaternary ammonium salt-co-N-[2-(pyridine-2-dithioalkyl)-ethyl]-acrylamide-co-methyl methacrylate (PPDM), which has redox-responsiveness, through free radical polymerization, and furthermoredissolving the polymer and a small-molecular medicine in an organic solvent to prepare redox-responsive drug-carrying colloid particles through a selective solvent method; and finally with a water dispersion liquid of the drug-carrying colloid particles as a deposition liquid, forming the coating on the surface of 316L stainless steel through electrophoretic deposition. The coating has excellentinhibition effect on escherichia coli and staphylococcus aureus and can achieve controllable releasing of a medicine by means of responsiveness to a reductive substance, e.g., glutathione. The preparation method has simple process and controllable conditions, is wide in adaptability on substrates, and is high in carrying rate of the medicine.

Provided is a method of preparing a stimuli-responsive multifunctional nanoparticle, including in sequence the steps of: (a) conjugating covalently an active targeting moiety to a hydrophilic polymer to form a targeted polymer, (b) conjugating covalently a redox-responsive moiety to the hydrophilic polymer of the targeted polymer to form a targeted redox-responsive polymer, (c) conjugating covalently a pH-responsive moiety of a drug complex to the redox-responsive moiety of the targeted redox-responsive polymer to form a targeted stimuli-responsive polymer-drug conjugate, wherein the drug complex includes a hydrophobic drug covalently linked to the pH-responsive moiety, and (d) adding the targeted stimuli-responsive polymer-drug conjugate and optionally an imaging agent into an aqueous liquid to allow self-assembly into a stimuli-responsive multifunctional nanoparticle, wherein the hydrophobic drug of the stimuli-responsive multifunctional nanoparticle forms a hydrophobic core, and the imaging agent is incorporated within the hydrophobic core.

The invention discloses a drug delivery material with pH and dual redox responsiveness and a preparation method and application thereof. According to the preparation method, an esterification productof N,N'-bis(tertbutyloxycarbonyl)-L-cystine and polyethylene glycol reacts with 2-Bromoisobutyryl bromide to obtain a macroinitiator; and then through atom transfer radical polymerization, deprotection and coupling with doxorubicin, (doxorubicin)2-cystine-(macrogol ester)2-b-(polymethylacrylic ferrocene methanoylethyl ester)2, namely the drug delivery material is obtained. The material is convenient to prepare, can be used as a drug carrier for physical coating of paclitaxel or a dimer thereof. The drug loaded micelle has high drug content, strong stability and good biocompatibility and has pH, dual or triple redox responsiveness. As the product contains at least one anti-cancer drug, the material can improve multi-drug resistance of human body, and effective treatment of tumors is achieved through different therapeutic mechanisms.

The invention relates to a redox response polypeptide hydrogel as well as a preparation method and application thereof, and belongs to the technical field of biomedical materials. The invention provides a polypeptide that can be self-assembled to form hydrogel, the polypeptide is dissolved in water and then forms a redox response hydrogel under crosslinking of H2O2. The hydrogel has a compact fiber network structure, relatively strong mechanical properties and good biocompatibility. The hydrogel has high sensitivity to glutathione (GSH), and the GSH responsive release of the drug can be realized by loading the doxorubicin hydrochloride into the hydrogel. The drug-loaded hydrogel is implanted into a tumor part through injection, so that the anti-tumor effect of the drug can be improved, and the toxic and side effects of the drug on normal tissues are effectively reduced.

The invention discloses redox sensitive polypeptide based on cell-penetrating peptide and application of the redox sensitive polypeptide in a vaccine vector. The sequence of the polypeptide is shown by SEQ ID NO:1. The polypeptide can be subjected to an electrostatic interaction with an antigen carrying a negative charge first, then cross-linking is performed with sulfydryl of cysteine, and the antigen is tightly wraped to form a stable polypeptide / antigen nano composite. In the nano composite, the sulfydryl of cysteine conducts spontaneous oxidation to form a disulfide bond, and the polypeptides are subjected to cross-linking to form a denser peptide / antigen condensation product. The redox sensitive polypeptide disclosed by the invention integrates the advantages of cell-penetrating peptide and the redox responding type disulfide bond cross-linking agent; by adopting new cell-penetrating peptide mediated redox responding type polypeptide as a vaccine adjuvant, the redox sensitive polypeptide overcomes the shortcoming that traditional immunologic adjuvant cannot induce an organism to generate strong antigen-specific cellular immunity, and is expected to be applied to clinical vaccine therapy.