126 results about "PAMAM dendrimer" patented technology

A polymer comprising recurring units represented by formula (I):

• • wherein X is selected from the group consisting of C(O)OR¹, C(O)SR¹, C(O)NR¹R², and VZ, where R¹ and R² are each individually selected from the group consisting of hydrogen, C₁ to C₁₀ alkyl, and C₆ to C₁₀ aryl, where V is a labile linker group, and where Z is selected from the group consisting of poly(ethyleneimine), poly(propyleneimine), poly(lysine), PAMAM dendrimer, octaamine dendrimer, and hexadecaamine dendrimer; and wherein Y is selected from the group consisting of —(CH₂)₂—, —(CH₂)₂—O—(CH₂)₂—, —(CH₂)₂—O—(CH₂)₂—, and —(CH₂)₃—NHC(O)—(CH₂)₆—C(O)NH—(CH₂)₃— is useful in nucleic acid delivery applications. Polyacetals of the formula (I) are preferably made by reacting appropriate diols and divinyl ethers. In preferred embodiments, complexes formed between polyacetals of the formula (I) and polynucleotides are useful as transfection reagents.

The invention relates to application of polyamide-amine (PAMAM) dendrimer coated ZnX (X=S, Se, Te) semiconductor quantum dots in fingerprint development, belonging to the technical field of material preparation. The method comprises the following steps: synthesizing a PAMAM dendrimer coated ZnX semiconductor quantum dot solution; and carrying out fluorescence labeling on latent fingerprints by using the PAMAM dendrimer coated ZnX semiconductor quantum dot solution. The method provided by the invention avoids the problem of toxicity of heavy metal ion Cd<2+> in the existing developing reagent, and the PAMAM dendrimer coated ZnX semiconductor quantum dots are harmless to the environment and users; the addition of the metal ion M<2+> can further enhance the fluorescence-emission strength of the ZnX semiconductor quantum dots; and by using the interaction between the PAMAM dendrimer and the fingerprint residue, the invention reserves the high development efficiency in the physical development method, and overcomes the defect of insufficient detailed development of fingerprint lines in the physical development method, thereby enhancing the precision and accuracy of the latent fingerprint development.

The invention relates to a preparation method of a silica gel-bonded polyamidoamine (PAMAM) dendrimer adsorbent. The preparation method comprises the following steps that 1, an amino functional group-containing silane coupling agent as a central nucleus and methyl acrylate undergo a Michael addition reaction to produce a semi-generation product G0.5 containing ester groups as terminal groups, the semi-generation product G0.5 and ethanediamine undergo an amidation reaction to produce a whole-generation product G1.0 containing amino groups as terminal group, and the Michael addition reaction and the amidation reaction are repeated to produce G0.5-G4.0 PAMAM dendrimers, and 2, the G0.5-G4.0 PAMAM dendrimers and a silica gel precursor tetraethoxysilane are mixed according to a mole ratio of 1: 1 to 1: 16 and undergo a synthesis reaction by a sol-gel method, and the reaction system respectively undergoes hydrolysis copolycondensation reactions in the presence of a pore forming agent and in the absence of the pore forming agent so that the silica gel-bonded PAMAM dendrimer adsorbent are obtained. The silica gel-bonded PAMAM dendrimer adsorbent has a large metal ion adsorption capacity, can be used for treatment on heavy metal ion wastewater and has a unique advantage in practical application.

The present invention discloses new types of poly(amidoamine) (PAMAM) dendrimer-cross-linked polyimide membranes and methods for making and using these membranes. The membranes are prepared by cross-linking of asymmetric aromatic polyimide membranes using a PAMAM dendrimer as the cross-linking agent. The PAMAM-cross-linked polyimide membranes showed significantly improved selectivities for CO₂/CH₄ compared to a comparable uncrosslinked polyimide membrane. For example, PAMAM 0.0 dendrimer-cross-linked asymmetric flat sheet poly(3,3′,4,4′-diphenylsulfone tetracarboxylic dianhydride-3,3′,5,5′-tetramethyl-4,4′-methylene dianiline) (DSDA-TMMDA) polyimide membrane showed CO₂ permeance of 135.2 A.U. and CO₂/CH₄ selectivity of 20.3. However, the un-cross-linked DSDA-TMMDA asymmetric flat sheet membrane showed much lower CO₂/CH₄ selectivity (16.5) and higher CO₂ permeance (230.8 GPU).

The invention provides a preparation method of a new adsorbent, the method uses a dendritic polymer to modify a graphene oxide adsorption material, and the graphene oxide adsorption material modified by the dendritic polymer can effectively adsorb lead ions, cadmium ions, manganese ions, copper ions and other heavy metal ions in wastewater. The method is as follows: first using graphite powder as a raw material to prepare multilayer graphene oxide by concentrated sulfuric acid, potassium permanganate and hydrogen peroxide oxidation, fully dissolving the graphene oxide in ethanol with the aid of ultrasonic, then adding a certain amount of the dendritic polymer for water bath reaction at 30-80 DEG C for 6 to 48 hours, performing vacuum suction filtration of an obtained product, then washing with the ethanol, and then drying at 50-100 DEG C to obtain a heavy metal adsorption material. SEM (scanning electron microscope) pictures show that the adsorbent has a loose structure, and the adsorbent has a good application prospect in heavy metal adsorption field. Adsorption experiments show that, under the condition of normal temperature, the adsorbent has a good adsorption capacity to the lead ions, cadmium ions, manganese ions and copper ions, and especially has a strong adsorption capacity to the lead ions, and the maximum adsorption amount can reach 300mg/g above.

The invention relates to an activation method for electromagnetic shielding fabrics before chemical plating based on PAMAM (polyamidoamine)/palladium ligand. The activation method includes four steps of preparing PAMAM dendrimer solution; preparing dendrimer PAMAM-palladium activating finishing liquor; performing fabric activation; and performing chemical plating. Compared with the prior art, theinvention provides a simple, convenient and stable preparation method for an activating agent with a high-efficient catalysis effect and the activation processing method before chemical plating. Accordingly, the activation method has excellent advantages that metal chemical initial plating of the electromagnetic shielding fabrics is easy, a plating layer is uniform and firm, and the like.

The invention relates to a method for preparing a superparamagnetic nanoparticle photocatalyst with a Fe3O4-PAMAM-TiO2 core-shell structure by using polyamide-amine (PAMAM) dendrimer as a template and an isolation layer in a low-temperature aqueous solution. The method is characterized by comprising the following steps: firstly, with the PAMAM dendrimer as the template, preparing a superparamagnetic Fe3O4-PAMAM nanoparticle colloidal solution by using a co-precipitation method; then adding the PAMAM dendrimer with different terminal groups and coating Fe3O4-PAMAM nanoparticles so as to form a dendrimer isolation layer; finally, dropwise adding a TiCl4 absolute ethanol solution, and carrying out normal pressure reaction and hydrothermal reaction so as to obtain the nanoparticles with the Fe3O4-PAMAM-TiO2 core-shell structure and a complete TiO2 shell layer; and carrying out washing and redispersion so as to obtain the nanoparticle photocatalyst with the Fe3O4-PAMAM-TiO2 core-shell structure.

The invention relates to a method for gene transfection by utilizing a PEG (polyethylene glycol) functionalized PAMAM (poly(amidoamine)) dendrimer carrier encapsulating gold nanoparticles. The method comprises the following steps: (1) preparing an activated mPEG (methoxypolyethylene glycol) solution, weighing a fifth-generation PAMAM dendrimer and dissolving the fifth-generation PAMAM dendrimer in DMSO (dimethyl sulfoxide), then adding the activated mPEG solution and carrying out magnetic stirring under room temperature to react to obtain a G5.NH2-mPEG10 solution; (2) dropwise adding an HAuCl4 aqueous solution to the G5.NH2-mPEG10 solution and quickly adding a NaBH4 solution after stirring to obtain a reaction product; (3) preparing a carrier/gene compound solution with the reaction product and pDNA (plasmid deoxyribonucleic acid) or siRNA (small interfering ribonucleic acid); (4) carrying out cell transfection by adopting the carrier/gene compound solution. The prepared carrier has the advantages of mild transfection conditions, easiness in operation, high transfection efficiency, good specificity and the like when being used for gene transfection and has good application prospect in cancer therapy and the like.

The invention discloses a dentritic heparin nano-material and a modified biological type artificial blood vessel. The dentritic heparin nano-material provided by the invention has a terminal branch unit shown in formula I, and is obtained by a reaction between polyamidoaminedendrimers using hydrazide group as a terminal group and heparin, wherein the inner core of the polyamidoaminedendrimers is cystamine, and the dentritic frame of the polyamidoamine dendrimers is hydrazide modified polyamidoamine including -0.5, 0.5, 1.5, 2.5, 3.5, 4.5, 5.5, 6.5 and 7.5; and the connection between the heparin and polyamidoamine is a glycosidic bond formed a reaction between the hydrazide on the surface of the polyamidoamine and the heparin reducing terminal. The disulfide bond in the dentritic heparin nano-material is cut through a reducing agent to obtain a sulfydryl site which can react with an intravascular stent material; and the surface in a blood vessel can be activated through a coupling agent of a two-way functional group, and the heparin with a branch structure can be fixed on the inner surface of the blood vessel material through chemical bond covalence, so that a composite artificial blood vessel with an anticoagulation effect can be obtained.

The invention provides a preparation method of a ZnO/graphene oxide composite photocatalysis material. The ZnO/graphene oxide composite photocatalysis material is a ZnO/PAMAM/graphene oxide composite material. The preparation method of the ZnO/graphene oxide composite photocatalysis material comprises the following steps: introducing amino groups to the surface of graphene oxide, forming PAMAM dendrimers on the surface of graphene oxide through using a Michael addition reaction of methyl acrylate and ethylene diamine, and forming ZnO on the surface of the PAMA dendrimer modified graphene oxide in an in situ manner by using the coordination between Zn<2+> and tertiary amino groups and amido groups on the PAMAM and hydroxyl groups and carboxyl groups on the surface of graphene oxide. The composite material prepared in the invention has excellent adsorption performance and photocatalytic activity on common organic pollutants.

The invention discloses a preparation method for dressing polyamidoamine dendrimer by amino acid. The reaction is performed in organic solvent, hydroxyl benztriazole HOBt, 2-(1H-benzotriazole)-N, N N`, N`-tetramethyluroniumhexafluorophosphate HBTU, N and N-diisopropylethylamine DIPEA are taken as catalyzer, to ensure that 2, 2, 4, 6 and 7-pentamethyldihydrobenzofuran-5-sulfonyl Pbf and 9-fluorenylmethyloxycarbonyl Fmoc dual-protection amino acid and terminal hydroxyl group PAMAM dendrimer can generate the condensation reaction. The refinement is performed through adopting dextran gel chromatography, to ensure that trifuoroacetic acid and piperidine can respectively divest of the Pbf protecting group and the Fmoc protecting group of the amino acid and the depurant amino acid can be obtained to dress the PAMAM dendrimer of the terminal hydroxyl group. The operation of the preparation method is simple, the condition is moderate, the price is low, the purer end product can be obtained, the preparation process can not damage the activation of the guanidino in the amino acid, and the preparation method is suitable for a great quantity of preparation and industrialized production.

The present invention relates to a method for preparing superparamagnetic Fe3O4-PAMAM-ZnO / TiO2 nanoparticles with a core-shell composite structure by using a polyamide-amine (PAMAM) dendrimer as a template and a spacer layer in a low temperature aqueous solution. The method is characterized by comprising the following steps: first preparing a superparamagnetic Fe3O4-PAMAM nanoparticle colloidal solution by using a PAMAM dendrimer as a template, then adding a right amount of PAMAM dendrimer to wrap the Fe3O4-PAMAM nanoparticles, under alkaline condition adding a solution of soluble zinc salt and a titanium tetrachloride solution at the same time; conducting atmospheric reaction and a hydrothermal reaction to obtain the superparamagnetic Fe3O4-PAMAM-ZnO / TiO2 nanoparticles with core-shell composite structure and with a complete ZnO/TiO2 composite shell layer. The particles can be dispersed in the form of individual particle in solution, and has high photocatalytic activity and magnetic recovery rate.

The invention provides a preparation method for 2.0 generation of polyamidoamine (PAMAM) dendrimer, and belongs to the technical field of polymer materials. The method adopts a 'one-pot method' to synthesize PAMAM dendrimer, which greatly reduces synthetic procedures, lowers preparation cost, greatly reduces raw material and solvent consumption, and reduces separating frequency and dendrimer synthesize cost. The method can accelerate the realization of large-scale application of the PAMAM dendrimer in related industrial fields.

The invention relates to an amphiphilic self-assembled nanomicelle based on nano Low-generation PAMAM (polyamidoamine) dendrimer and application thereof, particularly obtained conjugating low-generation PAMAM dendrimer and a hydrophobic agent and self-assembling in water via ultrasonic vibration. The nanomicelle has active molecules or a prodrug with drug loading capacity; the chemical conjugation of the hydrophobic agent and the low-generation PAMAM dendrimer helps improve the defects of poor solubility of the hydrophobic drug and low bioavailability, and a new idea is provided to solve the problem that traditional clinical chemotherapeutics are high in toxicity and low in safety coefficient; the nanomicelle can also function as a nanocarrier to carry other hydrophobic drugs, enabling joint use of drugs and enhancing therapeutic effect.

The present invention discloses a method for separating flavonoid substances in Camellia nitidissima Chi based on a magnetic nanoparticles-PAMAM nano composites, which comprises the following steps: preparing PAMAM dendrimer, then using the PAMAM dendrimer to prepare the magnetic nanoparticles-PAMAM nano composites, then adding the obtained magnetic nanoparticles-PAMAM nano composites in a Camellia nitidissima Chi extract, extracting and performing magnetic separation on the flavonoid substances in Camellia nitidissima Chi under ultrasound or microwave condition. According to the present invention, flavonoid substances with faintly acid characteristics are extracted and adsorbed in a plant concentrate such as Camellia nitidissima Chi or Hedyotis diffusa etc. based on the magnetic nanoparticles-PAMAM nano composites, in a successive step, high efficiency separation of the flavonoid substances can be realized by the technologies such as magnetic separation and microwave-assisted extraction.

The invention discloses a PHBV (poly(3-hydroxybutyrate-co-3-hydroxyvalerate)) composite material as well as a preparation method and applications thereof. The preparation method comprises the following steps: adding PHBV resin in a solvent, stirring at the temperature of 55-65 DEG C, and performing condensation reflux for 3-5 hours to prepare a PHBV solution; adding a polyamide-amine dendrimer solution in the PHBV solution, heating and stirring for 4-6 hours to prepare a mixed solution of PHBV/polyamide-amine dendrimer; pouring the mixed solution of PHBV/polyamide-amine dendrimer into a mould, spreading a film and volatilizing the solvent to obtain the PHBV composite material. According to the preparation method of the PHBV composite material, the special three-dimensional structure of PAMAM (polyamide-amine) dendrimer and a large number of cavity structures in the PAMAM dendrimer are utilized to destroy the regularity of PHBV, and the molecular chain segments of PHBV are allowed to extend towards all directions to reduce the crystallinity of PHBV, so that the toughness of the PHBV composite material is enhanced.

The invention discloses a preparation method for magnetic carbon fibers with a good interface property. The preparation method comprises the following steps: step 1, carrying out acid oxidation treatment on carbon fibers; step 2, carrying out acylating chlorination treatment on the carbon fibers; step 3, grafting a PAMAM (Polyamide Amide) dendrimer on the surfaces of the carbon fibers; step 4, preparing a nano iron-cobalt alloy on the surfaces of the carbon fibers. The PAMAM dendrimer is highly symmetrical; the surface of the PAMAM dendrimer contains a lot of amino functional groups and the interior of the PAMAM dendrimer contains a lot of nano cavities to be used as a template to obtain nano iron-cobalt alloy grains on the surfaces of the carbon fibers, so that the magnetism of the carbon fibers is functionalized and the carbon fibers can be used for preparing an electromagnetic shielding material; the interface bonding strength between the carbon fiber and base body resin can be greatly improved and the interface performance of a composite material is improved.

The present invention provides compositions comprising PAMAM dendrimers conjugated with one or more biologically active agents, and their use systemically to target activated microglia/macrophages in retina/choroid and generally, inflammatory and/or angiogenic diseases of the eye.

The invention provides a modified multi-walled carbon nanotube modified cement-based composite material, which comprises the following components by weight: 24-30 parts of cement, 60-90 parts of riversand, 15-30 parts of siliceous lime, 5-10 parts of reinforced fiber, 3-5 parts of modified multi-walled carbon nanotubes, 0.5-1.5 parts of a polycarboxylate-type water reducing agent, 1-2 parts of adefoaming agent and 10-15 parts of water. According to the preparation method, hydroxyl and polyamide-amine dendritic polymers are adopted for jointly modifying the multi-walled carbon nanotubes for the first time, so that the properties such as compressive strength and breaking strength can be remarkably improved; the reinforced fibers are uniformly dispersed in the slurry structure so as to be firmly combined with a cement-based material, so that the crack resistance and the excellent impact resistance of the cement-based composite material are improved.

The invention relates to a composite thin film anode catalyst applied to a direct methanol fuel cell (DMFC), in particular to a self-assembled composite film of polyoxometallate-Ptnano and PAMAM dendrimer which is applied to the anode catalyst for the DMFC, and a preparation method thereof. At first, a glassy carbon electrode substrate is cleaned, and then, a layer-by-layer self-assembling method is utilized to prepare the anode catalyst capable of being applied to the DMFC, the procedure is characterized in that: putting the cleaned glassy carbon electrode substrate in p-amino thiophenol alcohol solution to carry out cationization, carrying out first-time circular scanning in the solution containing polyoxometallate and chloroplatinic acid; and finally putting in PAMAM dendrimer solution which takes HCl solution as solvent to carry out the second-time circular scanning; and repeating the above scanning process for 2-7 times. The prepared composite thin film has good catalytic activity on the oxidization of methanol, the activity is reinforced with the increasing of the layer number of the thin film, and polyoxometallate and PAMAM in the composite film have good promotion function on the oxidization of Pt-catalyzed methanol.

The invention discloses a PAMAM dendrimer supported Schiff base compound as well as a preparation method and an application thereof. According to the preparation method, ethylenediamine is taken as a kernel, a Micheal addition reaction and an amidation of ester between the ethylenediamine and methyl acrylate are performed repeatedly to obtain a branch, and a Schiff base compound is grafted on the tail end of branch to obtain the PAMAM dendrimer supported Schiff base compound. The prepared PAMAM dendrimer supported Schiff base compound has the characteristics of large adsorption quantity and high adsorption capacity for heavy metal in smoke, the effect of reduction of the release amount of the heavy metal in main stream smoke of cigarettes can be effectively realized if a few compounds are added to cigarette filter sticks, and the compound is simple in preparation process and suitable for industrial production.

The invention relates to a method for preparing paramagnetic Fe3O4-PAMAM-ZnO-TiO2 core-shell-shell-structured nanoparticles by taking polyamide-amine(PAMAM) dendrimers as a template and a separation layer in a low-temperature aqueous solution. The method is characterized in that firstly, the PAMAM dendrimers are firstly taken as the template, and a paramagnetic Fe3O4-PAMAM nanoparticle colloidal solution is prepared by adopting a coprecipitation method; secondly, the PAMAM dendrimers are added to wrap Fe3O4-PAMAM nanoparticles; thirdly, under the alkaline condition, soluble zinc salt is added to generate a ZnO shell layer; fourthly, a titanium tetrachloride solution is added to generate a TiO2 shell layer, and then the paramagnetic Fe3O4-PAMAM-ZnO-TiO2 core-shell-shell-structured nanoparticles with the complete ZnO shell layer and TiO2 shell layer are prepared. The nanoparticles can be dispersed into a solution in a single particle mode and have the higher photocatalytic activity and magnetic recovery rate.

The invention discloses a preparation method of high-content troxerutin and belongs to the technical field of pharmaceutical chemistry. The preparation method is characterized in that the preparationmethod of high-content troxerutin comprises the following steps: carrying out acetylation and purification of crude rutin used as a raw material, then hydrolyzing the crude rutin to obtain high-content rutin with a content being higher than 99.0%; reacting the high-content rutin under the catalysis action of a catalyst which is a third-generation PAMAM dendrimer to prepare troxerutin; and purifying the troxerutin to obtain the high-content troxerutin with a content being higher than 99.0%. According to the method, the high-quality rutin with the content being higher than 99.0% is used as the raw material, so that the high-content troxerutin crude drug is prepared; the method is low in cost and simple and convenient in steps, is economical and environmentally friendly, and is suitable for industrial production; the content of the prepared troxerutin can reach 99.0% or above.