45 results about "Dihydroxyphenylalanine" patented technology

The invention relates to a method for separating and purifying mussel mucin by using a mixed adsorption chromatography. Mussel mucin contains a group of L-3,4- -Dihydroxyphenylalanine (L-DOPA), a phenohydroxyl group thereof can act as the supplier for hydrogen bond, the benzene ring thereof can generate a hydrophobic effect, and the lysine thereof with strong positive charges is capable of forming a static bond. On the basis of the properties of mussel mucin, a mixed adsorption chromatography (i.e. the adsorption chromatography based on three principles of adsorption with hydrogen bond, adsorption with hydrophobic effect, and static adsorption) is adopted to overcome the problem of low yielding rate of mussel mucin in the prior art for separating and purifying mussel mucin. An strong acid extraction is adopted to eliminate small-molecular compounds from a desalting column, an argar medium with high concentration and high cross-linking degree to separate and purify mussel mucin, and an acetic acid-urea- polyacrylamide gel electrophoresis is used to differentiate mussel mucin through specific chromogenesis with nitro blue tetrazolium. Three principles adopted with one separation medium to separate mussel mucin achieve high selectivity, simplify the purification technology, and decrease production cost.

The invention relates to dihydroxyphenylalanine derivatives, the production thereof, and pharmaceutical compositions containing said dihydroxyphenylalanine derivatives. The invention further relates to the use of said dihydroxyphenylalanine derivatives and pharmaceutical compositions for the treatment and prevention of movement disorders, neurodegenerative diseases, Alzheimer, Parkinson's disease, hemiatrophy hemiparkinsonism, Parkinson's syndrome, Lewy bodies disease, frontotemporal dementia, Lytico-Bodig disease (Parkinsonism-dementia-amyotrophic lateral sclerosis, striatonigral degeneration, Shy-Drager syndrome, sporadic olivopontocerebellar degeneration, progressive pallidal atrophy, progressive supranuclear palsy, Hallervorden-Spatz disease, Huntington's disease, X chromosome-linked dystonia (Morbus Lubag), mitochondrial cytopathy with striatal necrosis, neuroacanthocytosis, restless leg syndrome, Wilson's disease.

The inventors disclose here a novel, facile approach to the synthesis of acetonide-protected catechol-containing compounds having at least one amine group. In specific embodiments, the invention provides novel methods of synthesizing 3,4-dihydroxyphenylalanine (H-DOPA(acetonide)-OH (6)), Fmoc-protected H-DOPA(acetonide)-OH (Fmoc-DOPA(acetonide)-OH (7)), Fmoc-protected dopamine (Fmoc-dopamine(acetonide) (10)), TFA-protected dopamine (TFA-dopamine(acetonide) (13)) and acetonide-protected 4-(2-aminoethyl)benzene-1,2-diol (acetonide-protected dopamine (14)).

The inventors disclose here a novel, facile approach to the synthesis of acetonide-protected catechol-containing compounds having at least one amine group. In specific embodiments, the invention provides novel methods of synthesizing 3,4-dihydroxyphenylalanine (H-DOPA(acetonide)-OH (6)), Fmoc-protected H-DOPA(acetonide)-OH (Fmoc-DOPA(acetonide)-OH (7)), Fmoc-protected dopamine (Fmoc-dopamine(acetonide) (10)), TFA-protected dopamine (TFA-dopamine(acetonide) (13)) and acetonide-protected 4-(2-aminoethyl)benzene-1,2-diol (acetonide-protected dopamine (14)).

Methods of synthesizing a DOPA-melanin (DM) polymer are disclosed, as well as compositions comprising the DM polymer and uses thereof. The method comprises contacting a reactant such as 3,4-dihydroxyphenylalanine (DOPA) with a high concentration aqueous salt solution under oxidative conditions. The resulting DM polymer may form as insoluble particles or as a coating on a substrate surface. Exemplary uses for the DM polymers include removing heavy metal ions from contaminated solutions or capturing and delivering cationic drugs such as gentamicin.

The invention relates to a preparation method and applications of a polyvinylamine polymeric flocculant containing dihydroxyphenylalanine functional groups, which belong to the technical field of environment-friendly water treatment. The polyvinylamine polymeric flocculant is prepared through the steps of mixing, coupling-reacting and separating. Compared with the existing traditional polymeric flocculant, the polyvinylamine polymeric flocculant as well as a flocculant and a mud cake dehydrant applied to sewage treatment are greatly enhanced in flocculation effect, thereby greatly reducing the turbidity of sewage under low concentration dosage of chemical agents.

The invention provides an aromatic amino acid polymer which is prepared by using aromatic ring-containing amino acids such as L-beta-p-hydroxybenzoate alanine (L-tyrosine, Tyr), 2-hydroxyphenylalanine (2HPA), L-3,4-dihydroxyphenylalanine (dopa, L-DOPA ) and the like as monomers, protecting the amino, performing fusion polycondensation, and then de-protecting under an acidic condition to obtain the finish product. The polymer provided by the invention is quite good in degradability and biocompatibility, and can be used as degradable materials for organization engineering materials, package materials, environmentally friendly cleaning agents, detergents and other fields, and also for adsorption of inorganic particles.

Acrylate adhesive composition comprising N-methacryloyl-3,4-dihydroxyphenylalanine and / or N-acrylol-3,4-dihydroxyphenylalanine. The adhesive composition ensures an adhesion of substrates under moist conditions, in particular a biocompatible and waterproof adhesion to human skin.

The invention discloses an autism diagnosis kit, the autism diagnosis kit comprises a reagent for detecting the intestinal microbial metabolite concentration, wherein the intestinal microbial metabolite comprises at least one of acetic acid, tyramine, histamine, gamma-aminobutyric acid, dihydroxyphenylalanine and norepinephrine. The acetic acid content and the score of the severity degree of the autism are in a negative correlation relationship; the contents of tyramine, histamine, gamma-aminobutyric acid, dihydroxyphenylalanine and norepinephrine are respectively in positive correlation withthe severity of autism, and the autism is diagnosed through the intestinal microbial metabolite level of an excrement sample, so that the kit has relatively high accuracy. Therefore, the intestinal microorganism metabolite combination level of a subject can be used as an index for screening and diagnosing autism under the conditions of scientific research and clinical application.

This invention relates to protein-based adhesives that are capable to adhere to a substrate in a dry, wet, moist, or an aqueous environment. Particularly, said adhesives comprise a crosslinking agent and an elastin-like polypeptide (ELP) that contain tyrosine, lysine, cysteine, dihydroxyphenylalanine (DOPA) or trihydroxyphenylalanine (TOPA) amino acid residue, or a combination thereof, on the polypeptide chain of said ELP. Among others, the adhesives disclosed herein may find broad applications in medical treatments and surgical operations. Compositions and methods of use are within the scope of this application.

The invention discloses an orthopaedic material surface coating for promoting osteogenesis and immunoregulation and a preparation method thereof. The coating is attached to the surface of an orthopaedic material through a medium by active peptides of a bone morphogenetic protein 2 , the amino acid sequence of the active peptides of the bone morphogenetic protein 2 is KIPKASSVPTELSAISTLYL, and the medium is a peptide sequence which includes a plurality of 3,4-dihydroxyphenylalanine DOPA. The preparation steps of the coating are simple and feasible, large equipment is not needed, the reaction is stable, and the environment will not be polluted. Experimental results show that compared with a coating prepared through a traditional material surface modification method, the material surface coating prepared through the preparation method has the functions of promoting osteogenesis and immunoregulation, and a new way is provided for further application of orthopedic materials to the fields of trauma and scaffold for tissue engineering.

The invention belongs to the field of cell separation and analysis and particularly relates to mussel bionic polypeptide composite magnetic beads and a preparation method and application thereof. Themussel bionic polypeptide composite magnetic beads utilize the boron affinity reaction of phenylboronic acid and 3,4-dihydroxyphenylalanine to fix a mussel bionic polypeptide with one end containing atumor cell specific recognition sequence to the surface of a magnetic microsphere modified by a phenylboronic acid-based high molecular polymer, and are used for capturing and releasing circulating tumor cells. The mussel bionic polypeptide composite magnetic beads have the advantages of adoption of the simple and easily available raw materials, low cost, simple preparation process, mild reactionconditions, difficult deterioration, degradation and the like of the mussel bionic polypeptide, and have strong practicability.

It is an object to provide a radical scavenger, an active oxygen-scavenging agent and the like, which are highly efficacious clinically and novel, and so as to attain the object, 3,4-dihydroxyphenylalanine derivatives such as N-β-alanyl-5-S-glutathionyl-1-3,4-dihydroxyphenylalanine (5-S-GAD) or pharmaceutically acceptable salts thereof are contained as an active ingredient.

The invention relates to a preparation method of an external wall dustproof coating, and belongs to the technical field of external wall coatings. The preparation method disclosed by the invention comprises the steps as follows: firstly, using malvaceae pollen with a micron-sized particle size as a raw material, and performing a reaction on the malvaceae pollen and 3,4-dihydroxyphenylalanine underthe action of catechol oxidase to obtain reaction filter residues; then performing a reaction on the reaction filter residues and a mixed saline solution of iron salt and sodium bicarbonate to obtaina self-made dustproof filler; then using organic silicon modified acrylic resin as a paint base stock; and finally, mixing the self-made dustproof filler with the organic silicon modified acrylic resin as well as other auxiliary materials to prepare paint, then brushing the paint on a wall surface, applying magnetic field processing to the brushed paint, and finally, naturally curing to form theexternal wall dustproof coating. The dustproof coating prepared with the preparation method disclosed by the invention is very excellent in dustproof effect; and as time goes by, a double-micro-synaptic-junction structure is generated on the surface of the coating, and thus, a contact angle is further increased, the dustproof effect is very excellent, and the coating has a wide application prospect.

The invention discloses a method for efficiently preparing melanin under photo-induction. According to the method, efficient preparation of melanin is realized under photo-induction by taking any one or more of L-tyrosine, L-phenylalanine, L-tryptophan, 3, 4-dihydroxyphenylalanine, L-arginine and L-alanine as reaction precursors and any one of transition metal complex / persulfate, thioxanthone or dye / tertiary amine as a photo-initiation system. A photo-initiation system and an amino acid reaction precursor are mixed, and the mixture is irradiated under light with a specific wavelength to react for a certain time to obtain a reaction product; and the product is further centrifuged, filtered, dried, the residual photoinitiator, unreacted amino acid and the like are removed, and finally a melanin product is obtained. Compared with the prior art, the method is simple in preparation process, convenient to operate, high in efficiency and low in cost.

The invention relates to a method for preparing a tyrosinase mimetic enzyme, the preparation method takes Beta-cyclodextrin as a model, the tyrosinase mimetic enzyme with the natural enzyme activity is obtained by the complexation with Cu2+ on the basis of cyclodextrin dual-histidine derivatives which are obtained by preparation, the tyrosinase mimetic enzyme can catalyze the oxidation of tyrosine to generate dihydroxyphenylalanine; compared with the prior art, the preparation method is characterized by high catalytic activity, no inactivation, and the like.

The invention provides a fluorescent copper nano-cluster as well as a preparation method and application thereof. The preparation method comprises the following steps: mixing 2-20 parts by volume of a3, 4-dihydroxyphenylalanine aqueous solution of 0.01-0.1 mol.L <-1 > and 2-20 parts by volume of a copper salt aqueous solution of 0.01-0.1 mol.L <-1 >, uniformly stirring the mixed solution, and carrying out microwave heating to obtain a fluorescent copper nano-cluster solution. The invention has the advantages of simple preparation process, low instrument requirements, controllable reaction conditions, short treatment time, low cost and the like; addition of reducing agents such as hydrazine hydrate and ascorbic acid is avoided; the prepared copper nano-cluster has the advantages of small size, good water solubility, strong photobleaching resistance and the like; the copper nanocluster prepared by the method can generate fluorescence, the fluorescence emission peak of the copper nanocluster is about 514nm, the quantum yield of the fluorescent copper nanocluster can be up to 0.58%, and the prepared copper nanocluster has high sensitivity and selectivity to body iron ions and can be used for constructing an iron ion sensing system.

The invention discloses a production technology of Mucuna Pruriens extract products, and belongs to the technical field of advanced processing of Mucuna Pruriens. The technology comprises the following steps: processing Mucuna Pruriens to obtain Mucuna Pruriens powder; adding vitamin B3 and citric acid into water to achieve dissolving, adding the Mucuna Pruriens powder, performing uniform mixing,carrying out ultrasonic extraction, then carrying out refluxing extraction, adjusting the pH value of the obtained solution to 4.5-5.5, standing the obtained solution for precipitation to obtain an extract liquid, centrifuging the extract liquid, and drying the obtained precipitate and mother liquor to obtain Mucuna Pruriens extract I; and concentrating the above obtained supernatant to obtain a crude product, and refining, drying, crushing, mixing and packaging the crude product to obtain Mucuna Pruriens extract II. The technology has the advantages of less flow, no pollutant emission, high yield and high purity of the Mucuna Pruriens extract products, small consumption of an extractant, and easiness in industrial production. The cost of the technology is far lower than that of traditional technologies, and is close to the blending cost of low-content dihydroxyphenylalanine. A series of products containing 10-99% of the Mucuna Pruriens extract products can be produced through the technology, so the technology can meet demands of different clients, and ensures the sales quality of the products.

The present invention relates, generally to a method of determining and assessing L-3,4-dihydroxyphenylalanine (a.k.a., Levodopa; L-dopa; or LD) metabolic capacity in an individual mammalian subject via a breath assay, by determining the relative amount of 13CO2 exhaled by the subject upon intravenous or oral administration of a 13C-labeled substrate, such as levodopa. The present invention is useful as an in vivo phenotype assay for individualizing LD / Carbidopa(CD) therapy in Parkinsons disease patients by optimizing the dose and timing of the dose of dopamine decarboxylase (DDC) inhibitor like CD for systemic suppression of dopamine metabolism by evaluating DDC enzyme activity using the metabolite 13CO2 in expired breath.

The invention relates to a single-component self-crosslinking waterborne polyurethane flame-retardant dispersion liquid as well as a preparation method and application thereof, and belongs to the technical field of coatings. The technical problem that in the prior art, a single-component polyurethane coating is cured under the influence of humidity and temperature is solved, and the comprehensiveperformance of the single-component polyurethane coating is further improved. The dispersion liquid disclosed by the invention is prepared from, by weight, 60-70 parts of polyhydric alcohol, 25-30 parts of isocyanate, 2-8 parts of a compound flame retardant, 20-25 parts of 3,4-dihydroxyphenylalanine, 5-10 parts of amphiphilic carbon nanodots, 3-5 parts of wax oil modified activated carbon, 8-12 parts of dimethylolbutyric acid, 5-10 parts of ethylene glycol, 1-2 parts of azodiisobutyronitrile, 6-12 parts of triethylamine, 0.5-2 parts of lauryl sodium sulfate, 1-2 parts of isooctyl alcohol phosphate and 150-250 parts of water. The water-based polyurethane coating containing the dispersion liquid is good in mechanical property and good in weather resistance, strong in adhesive force, good incorrosion resistance, good in flame retardancy and simple in construction.

Methods of synthesizing a DOPA-melanin (DM) polymer are disclosed, as well as compositions comprising the DM polymer and uses thereof. The method comprises contacting a reactant such as 3,4-dihydroxyphenylalanine (DOPA) with a high concentration aqueous salt solution under oxidative conditions. The resulting DM polymer may form as insoluble particles or as a coating on a substrate surface. Exemplary uses for the DM polymers include removing heavy metal ions from contaminated solutions or capturing and delivering cationic drugs such as gentamicin.

Prostate cancer comes in various forms and has proven difficult to treat. Provided herein are various methods and compositions for treating all forms of prostate cancers with dopa decarboxylase (DDC) inhibitors. These dopa decarboxylase inhibitors include carbidopa (α-Methyl-dopahydrazine), MFMD (α-monofluoromethyldopa), NSD-1015 (3-hydroxybenzylhydrazine), Methyldopa (L-α-Methyl-3,4-dihydroxyphenylalanine) or benserazide, and the inhibitors may be used in combination. DDC inhibitors may also be used to inhibit the progression of prostate cancer to androgen-independence and neuroendocrine prostate cancer.

The invention discloses an orthopedic medical bonding material with an antibacterial effect and a preparation method thereof, and the orthopedic medical bonding material comprises the following raw materials in parts by weight: 45-60 parts of self-made modified calcium phosphate bone cement, 12-18 parts of N-octyl-alpha -cyanoacrylate, 15-24 parts of dopamine, 4-10 parts of sodium alginate, 3-6 parts of lecithin, 5 to 10 parts of 3, 4-dihydroxyphenylalanine, 11 to 16 parts of collagen, 8 to 15 parts of chitosan, 3 to 5 parts of tyrosine, 3 to 5 parts of phenylalanine and 3 to 6 parts of 3-p-chlorophenoxy-1, 2-propylene glycol. The medical binding material for the orthopedics department prepared by the invention has excellent antibacterial and bactericidal effects and good compressive strength.

The invention belongs to the field of bone injury repair medical materials, and discloses scattering-resistant and high-strength composite calcium phosphate bone cement, a method for preparing the same and application of the scattering-resistant and high-strength composite calcium phosphate bone cement. The scattering-resistant and high-strength composite calcium phosphate bone cement comprises calcium phosphate bone cement and hydroxypropyl benzoic acid-g-chitosan. The weight of the hydroxypropyl benzoic acid-g-chitosan is 0.2-3% of the weight of the calcium phosphate bone cement, and 3, 4-dihydroxyl phenylpropionic acid or 3, 4-dihydroxy phenyl acetic acid and chitosan are coupled with each other to obtain the hydroxypropyl benzoic acid-g-chitosan. The scattering-resistant and high-strength composite calcium phosphate bone cement, the method and the application have the advantages that the scattering-resistant and high-strength composite calcium phosphate bone cement is excellent inbiocompatibility as compared with ordinary calcium phosphate bone cement, the strength, the scattering-resistant performance and the biocompatibility of the calcium phosphate bone cement can be improved by the aid of the excellent adhesion properties of Dopa-CS (dihydroxyphenylalanine-chitosan) and the excellent biocompatibility of the CS, the original solidification characteristics of the calciumphosphate bone cement further can be kept, and the solidification time of the calcium phosphate bone cement rarely can be affected; the scattering-resistant performance and the compressive strength can be obviously improved, and the scattering-resistant and high-strength composite calcium phosphate bone cement can be applied to the field of bone injury repair.

The invention discloses a novel method for synthesizing danshensu. The method uses tyrosine ammonia lyase, phenylpyruvate reductase and glucose dehydrogenase to catalyze levodopa to produce danshensu. Specifically, 0.5-1.5mol of levodopa (3,4-dihydroxyphenylalanine), 10-30g / L of wet bacterium of tyrosine ammonia lyase, and 10-30g of wet bacterium of phenylpyruvate reductase / L, 10-30g / L of wet cells of glucose dehydrogenase were placed in a reactor and mixed evenly, the pH value was adjusted to 7.0, the temperature was 30°C, and the catalytic reaction was carried out for 16-20h to obtain Danshensu. For the first time, the method uses tyrosine ammonia lyase, phenylpyruvate reductase and glucose dehydrogenase to produce danshensu enzymatically with levodopa as a substrate, saving raw materials and avoiding the pollution of chemical synthesis.

The invention provides a preparation method of a circulating nanoparticle enhanced antistatic PET packaging material. The preparation method comprises the following steps: S1, preparing ethylene glycol phthalate; s2, dissolving a multifunctional branching agent in dimethyl sulfoxide, then adding into sodium hydrogen sulfate, adding 3, 4-dihydroxyphenylalanine at a certain temperature, and reacting to obtain a modified branching agent; s3, dissolving the modified branching agent in a metal chloride solution to obtain a metal complexing branching agent; s4, preheating a metal complexing branching agent and a functional branching agent, adding the metal complexing branching agent and the functional branching agent into the ethylene glycol terephthalate prepared in the step S1, adding a thermal stabilizer, and reacting to obtain a metal-branched PET copolyester chip; and S5, processing the metal-branched PET copolyester chip into any form needing the PET packaging material. According to the invention, an antistatic agent does not need to be directly added, and metal is directly used as an effective component in a PET molecular chain, so that a lasting antistatic effect is achieved.

The invention discloses a preparation method of a 3, 4-dihydroxyphenylalanine chelated cerium ion composite proton exchange membrane with high chemical durability, which comprises the following steps: adding perfluorosulfonic acid resin into a mixed solvent of water, n-propyl alcohol and DMSO, and stirring at room temperature to obtain a uniform PFSA ionomer solution; the preparation method comprises the following steps: mixing and stirring 3, 4-dihydroxyphenylalanine and cerium salt in a water-ethanol solution to obtain a 3, 4-dihydroxyphenylalanine cerium complex dispersion liquid; the preparation method comprises the following steps: adding a 3, 4-dihydroxyphenylalanine cerium complex dispersion liquid into a PFSA ionomer solution, stirring to obtain a uniformly dispersed ionomer solution, dispersing the solution by using an ultrasonic cleaning machine, pouring the solution onto plate glass, blade-coating by using a winding bar, and finally drying, annealing and forming a film to obtain the product. The operation steps are simple, and the chemical durability of the composite proton exchange membrane is improved on the premise that the proton conductivity loss of the proton exchange membrane is not large. The invention aims to solve the problem of durability in the field of proton exchange membranes, and has a better popularization prospect.