95results about How to "Good pH responsiveness" patented technology

The invention discloses a preparation method and application of pH-responsive amino sodium lignosulphonate. The preparation method comprises the following steps: dissolving sodium lignosulphonate in water to prepare a sodium lignosulphonate water solution, regulating the pH of the solution to be 10-13, and activating at 50-70 DEG C for 0.5-1.0 hour; adding an amination modifier, dropwise adding an aldehyde reagent, and reacting at 70-90 DEG C for 2-4 hours after the dropwise adding, so as to obtain an amino sodium lignosulphonate water solution; extracting the obtained amino sodium lignosulphonate water solution by virtue of an alcohol reagent, washing residual solids by virtue of petroleum ether after the extraction, and carrying out freeze drying on washed remnants. The amino sodium lignosulphonate prepared by virtue of the preparation method has remarkable pH response characteristic; by regulating the pH of the water solution of the product, the molecular configuration and the aggregation extent of the product can be changed, and a regular nanoparticle structure can be spontaneously formed; the amino sodium lignosulphonate can be used as a wall material to be applied field of pesticide microcapsules and is hopefully applied to the field of lignin-based nanometer materials.

The invention provides a gel-based pH sensor and a preparation method thereof, belonging to the technical field of intelligent high molecules and sensors. The pH sensor is a composite material which takes polyvinyl alcohol gel as a matrix, and immobilizes and buries poly(acrylamide/methylacrylic acid) gel microspheres and immobilizes Congo red. The preparation method comprises the following steps: preparing a poly(acrylamide/methylacrylic acid) gel microsphere suspension; adding the microsphere suspension to polyvinyl alcohol aqueous liquor to crosslink and gelatinize; soaking a gel film in the Congo red for soaking, alkali treatment and washing to obtain a product. The gel-based pH sensor provided by the invention has the characteristics of absorbancy response and color response, so that visual simple measurement and precise measurement of pH value can be realized, and the using agility and application field of the pH gel sensor can be remarkably improved.

The invention provides a conductive photo-thermal self-healing composite hydrogel dressing as well as a preparation method and application thereof.The preparation method comprises the following steps:grafting acrylic acid on chitosan to obtain an N-carboxyethyl chitosan polymer; the preparation method comprises the following steps: grafting p-hydroxybenzaldehyde on a triblock copolymer to obtainan aldehyde-terminated polymer (PF127-CHO); the preparation method comprises the following steps: preparing an aldehyde-terminated polymer into a solution, adding carbon nanotubes into the polymer solution, and carrying out ultrasonic treatment in an ice bath to obtain an aldehyde-terminated/carbon nanotube dispersion liquid; the preparation method comprises the following steps: preparing an N-carboxyethyl chitosan polymer into a solution, mixing the solution with an aldehyde group-terminated/carbon nanotube dispersion liquid, and carrying out mutual crosslinking at 20-45 DEG C for 5-400 seconds to obtain the conductive, adhesive, self-healing, photo-thermal and nano composite hydrogel. The hydrogel has excellent adhesion, self-healing, pH response, biocompatibility and hemostatic performance, can show a photo-thermal behavior after being exposed to a near-infrared (NIR) region, causes physical damage to bacteria, and has huge potential for treating infected wounds.

The invention discloses a preparation method of a pH-responsive graphene /polymer nanometer hybrid material. The preparation method comprises the following steps: under the protection of inert gas of argon or nitrogen, carrying out an esterification reaction by using a reversible addition-breakage chain transfer polymerization chain transfer agent of hydroxyl and terminal carboxyl on the surface of graphene oxide to obtain a macromolecular chain transfer agent for reversible addition-breakage chain transfer polymerization; and then, carrying out reversible addition-breakage chain transfer polymerization under initiation of azodiisobutyronitrile to obtain the pH-responsive grapheme/polymethylacrylic acid-N,N-lignocaine ethyl ester nanometer hybrid material. The graphene oxide/polymer nanometer hybrid material not only ensures that the dispersibility of graphene in water is greatly improved but also has pH responsiveness, and can be widely applied to the fields of drug controlled release carriers, biosensors, intelligent nanometer materials and the like. The preparation method is simple and easy, and industrial production of materials can be realized, so that the method has good popularization and application values.

The invention discloses an amphiphilic waterborne segmented copolymer medicament carrier with pH responsiveness and biodegradability and a preparation method thereof. An amphiphilic waterborne segmented copolymer consists of a chain segment which is modified with polyphosphoester and polymethacrylate hydroxyethyl and contains carboxyl. A polyanion chain segment can be reversely converted into a hydrophilic or hydrophobic chain segment by adjusting the pH value of a medium. The amphiphilic polymer is self-assembled into a micelle under the condition of certain PH, and a shell of the micelle formed by a hydrophilic polyphosphoester chain segment can be used for better stabilizing the micelle. A hydrophobic polyanionic chain segment is used for forming an inner core of the micelle, is used for coating a hydrophobic medicament, and serves as a medicament carrier. The polyphosphoester chain segment has high biocompatibility and high biodegradability, and long in-vivo circulation of a medicament-carrying micelle can be realized. Under a weakly alkaline condition, the aims of dissociating the micelle, releasing a medicament and realizing controllable release are fulfilled.

The invention belongs to the technical field of preparation of detection materials, and relates to a preparation method of a magnetic ferroferric oxide nanosphere-based novel pH-responsive imprinted material. The preparation method comprises the following steps: firstly preparing ferroferric oxide nanoparticles and synthesizing mesoporous silicon dioxide coated ferroferric oxide nanospheres, and then performing chemical double bond modification on the mesoporous silicon dioxide coated ferroferric oxide nanospheres; finally, preparing the magnetic nanosphere-based pH-responsive imprinted material. The pH-responsive imprinted material prepared according to the preparation method provided by the invention can solve the problem that the surface of a base material is difficult to be directly coated with a molecularly imprinted polymer layer; the imprinted material adopts a significant core-shell structure consistent with the purpose of the invention; in addition, through combination of theperformance of the molecularly imprinted material and a pH-responsive intelligent material, the pH-responsive imprinted material is successfully applied to efficient detection of sulfamethoxazole.

The invention discloses a preparation method of an amphiphilic triblock copolymer modified ultrafiltration membrane with pH-responsive property. The method comprises the following steps: taking methylmethacrylate (MMA) and acrylic acid (AA) as raw materials, and preparing PAA-b-PMMA-b-PAA (PAMA) with a controllable structure by adopting reversible addition-fragmentation chain transfer (RAFT) polymerization. The amphiphilic triblock copolymer modified ultrafiltration membrane is directly prepared by adopting immersion precipitation phase inversion. According to a segregation behavior of the modifier on the membrane surface, the ultrafiltration membrane has a certain hydrophilic property and pollution resistance. The PMMA chain segments in the modifier PAMA adopted in the invention and polyvinylidene fluoride have excellent compatibility, and the membrane is kept stable in the application process. The PAA serving as a hydrophilic segment is enriched on the membrane surface and membranepores, the hydrophilic property of the membrane is improved, and adhesion of pollutants on the membrane surface and membrane pores is avoided. In addition, the ultrafiltration membrane has high anti-pollution capacity and retention rate of proteins and exists effective aperture conversion at the pH value of 3-8, and effective pore size regulation under external environmental stimulation is realized.

The invention relates to a cell membrane coated ultra-small ferroferric oxide nanocluster, and a preparation method and an application thereof. The method comprises the following steps: preparation ofultra-small ferroferric oxide nanoparticles, preparation of surface aminated ultra-small ferroferric oxide nanoparticles, preparation of ferroferric oxide nanoclusters, preparation of adriamycin-loaded ferroferric oxide nanoclusters, preparation of a cell suspension, and preparation of cell membrane coated ultra-small ferroferric oxide nanoclusters. After the nanocluster provided by the inventionis injected into a mouse body through a tail vein, T1/T2 bimodal MR imaging conversion can be achieved; meanwhile, the anti-tumor effect can be exerted; the chemotherapy effect of the nanocluster canbe further enhanced through a UTMD auxiliary means; and the nanocluster has potential clinical application value.

The invention relates to an electrical stimulation and pH dual response antibacterial injectable hydrogel and a preparation method and application thereof, first, a chitosan-polyaniline copolymer is prepared by grafting polyaniline onto chitosan; the chitosan-polyaniline copolymer is prepared into a solution, and the solution is mixed with an oxidized dextran solution for crosslinking at 25-40 DEGC for 30-800 seconds to get the electrical stimulation and pH dual response antibacterial injectable hydrogel; the mass ratio of chitosan-polyaniline copolymer and oxidized dextran is (1-5): (1-8). The CP / OD hydrogel has dual response to electrical stimulation and pH, meets the demand for specific time administration and has excellent antibacterial properties.

The invention belongs to the technical field of biomedical functional material preparation, and relates to a preparation method of a dynamic pH response chain based on a boric acid type metal organiccomplex. Therefore, a boronate ligand is introduced by utilizing the metal organic complex, then an anti-cancer drug doxorubicin (DOX) is loaded on through the porous structure of the metal organic complex, and hydrophilic biologic chain (PEG-NHS-PDA) is attached to serve as the dynamic response chain to achieve the purpose of sustained releasing and preventing the anti-cancer drug from releasingat will. Finally sialic acid on the surfaces of cancer cells is identified through the metal organic complex, and growing of the cancer cells is inhibited through a thermal therapy effect.

The invention relates to a pH (Potential of Hydrogen) responsive fluorescent carbon nanoparticle hybrid microgel and a preparation method thereof. The preparation method comprises the following steps: (1) weighing fluorescent carbon nanoparticles, using methylene dichloride to dissolve and prepare a fluorescent carbon nanoparticle solution, adding acyl chloride monomers, reacting for 10 h under room temperature, removing a reaction solvent, adding water, and drying through rotation; (2) weighing to obtain double-bonded fluorescent carbon nanoparticles, adding the double-bonded fluorescent carbon nanoparticles into distilled water, transferring the liquid into a reaction container, adding a cross-linking agent, sodium dodecyl sulfate and pH responsive polymer monomers after exhausting air, introducing nitrogen gas to exhaust the air, heating, and adding an initiating agent into a three-opening bottle after reaction liquid begins to backflow; (3) continuously introducing nitrogen gas and stirring, and carrying out a backflow reaction for 5-20 h at 50-90 DEG C; (4) filtering after cooling to room temperature, taking filter liquor, and placing the filter liquor in a dialysis bag for dialyzing for 48 h. The obtained product is free of biological toxicity, the grain diameter of the product is about 760 nm, fluorescent light has good pH responsiveness under the excitation of the same wavelength, and the product has a good application in the fields of drug release, pH sensing and catalysis.

The invention discloses a conductive collagen heart patch preparation method. The preparation method comprises the steps of preparing carbon nano tube dispersion liquid, crosslinking collagen and preparing a final patch. The method is simple and effective; the prepared conductive collagent heart patch has high mechanical property and strong electron conductivity and further has good biocompatibility, safety and easiness in biodegradation; the limitation that an ordinary heart patching material has poor toughness and electron conductivity and the like in a use process is solved; the conductivecollagen heart patch has a wide application prospect in the field of biological medical materials of tissue engineering and the like.

The invention discloses high-strength responsive hydrogel based on a block copolymer and a preparation method thereof, and belongs to the technical field of preparation of materials. A reactive amphiphilic triblock copolymer capable of self-assembling in water to form micelles is subjected as an intra-system macromolecular crosslinking point instead of the traditional crosslinker N,N-methylene diacrylamide to free radical polymerization with a monomer so as to obtain high-strength hydrogel having uniform crosslinking density. The reactive amphiphilic triblock copolymer is not electrically charged; the size and stability of the reactive amphiphilic triblock copolymer are scarcely influenced by ion strength or charge in a solution; therefore, the reactive amphiphilic triblock copolymer is applicable to most free radical polymerized monomers, and synthesis of intelligent functional hydrogel is facilitated. The preparation method herein is simple to perform; preparing is easy; the raw materials are good in safety and stability and are easy to store; the preparation process is green and safe, has short time and low byproduct production; a means is provided to prepare multifunctional high-strength hydrogel. The prepared hydrogel has excellent pH response and mechanical properties.

The invention discloses an injectable hydrogel dressing with pH response as well as a preparation method and application thereof. A polymer monomer and a tissue cross-linking agent monomer are subjected to free radical polymerization reaction to prepare the injectable hydrogel dressing with pH response. A double-bonded amino acid or a double-bonded amino acid derivative is subjected to an esterification reaction with -OH on NHS (N-hydroxysuccinimide) through -COOH of the double-bonded amino acid or the double-bonded amino acid derivative, and the tissue cross-linking agent monomer is prepared.The preparation method is simple to operate; the used raw materials are easy to obtain and low in price; and meanwhile, the prepared hydrogel dressing has good adhesiveness, pH responsiveness, injectability, self-healing performance and hemostatic performance, can effectively promote stomach hemostasis and wound healing after endoscopic therapy, and has huge application value in the fields of stomach hemostasis and wound healing.

The invention discloses a method for preparing double-stimulation responsive surface through secondary photopolymerization, relating to the field of grafting and modification of various base material surfaces. The method comprises the following steps: I, grafting pH responsive compound onto the surface by adopting a cracking type photoinitiator, wherein the pH responsive compound grafted onto the surface can be used as a hydrogen donor and a co-initiator of the next step reaction; and II, performing photopolymerization reaction on the basis by adopting a hydrogen abstracting type initiator, and grafting the double bond-modified photoresponse compound. The method not only has the advantage that the photopolymerization is efficient, energy-saving, economical, environment-friendly, and the like, but also the compound is difficult to drop after being grafted onto the surface through a covalent bond manner. The prepared intelligent surface has good photoresponsiveness, pH responsiveness, and the swelling property and wettability of the surface polymer can be reversibly controlled. The surface has potential application on the aspects of surface molecule switches, surface controlled release and ion adsorption due to good controllable wettability and mechanical effect.

The invention relates to a fibronectin-coated tannic acid/iron complex drug-loaded nano material and a preparation method and application thereof. The method comprises the following steps: adding doxorubicin hydrochloride into triethylamine for deprotonation, mixing an obtained hydrophobic doxorubicin solution and a tannic acid solution, adding iron salt for reaction, and mixing, stirring and extruding an obtained drug-loaded nano material of the tannic acid/iron complex loaded with doxorubicin and a fibronectin solution. The drug-loaded nano material prepared by the method not only can realize T1MR imaging, but also can play an anti-tumor immune effect through immunogenic death caused by chemotherapy and ferroptosis, and has potential clinical application value.