46results about How to "Low burst rate" patented technology

The invention provides sustained-release microparticles. According to the invention, a preparation method of the sustained-release microparticles is conducted at normal temperature or low temperature in a whole course, which is quite conducive to high-temperature sensitive drugs, in particular compositions which polymer matrixes prepared from protein, nucleic acid and peptide drugs. Compared with public technologies, the preparation method disclosed by the invention can keep bioactivity of active substances to the greatest extent in the entire technological process; meanwhile, the prepared sustained-release microparticles have an excellent sustained-release effect close to a zero level, and drug concentration is kept stable in a sustained-release period, so that shortcomings of microparticles, which are prepared by a conventional S / O / W (solid-in-oil-in-water) process which needs to prepare the drug microparticles in advance, that drug release fails to occur in an early stage while rapid drug release happens in a late stage are overcome; and moreover, the sustained-release microparticles are relatively high in drug loading ratio and drug entrapment efficiency.

The invention provides sustained-release microparticles. According to the invention, a preparation method of the sustained-release microparticles is conducted at normal temperature or low temperature in a whole course, which is quite conducive to high-temperature sensitive drugs, in particular compositions which polymer matrixes prepared from protein, nucleic acid and peptide drugs. Compared with public technologies, the preparation method disclosed by the invention can keep bioactivity of active substances to the greatest extent in the entire technological process; meanwhile, the prepared sustained-release microparticles have an excellent sustained-release effect close to a zero level, and drug concentration is kept stable in a sustained-release period, so that shortcomings of microparticles, which are prepared by a conventional S / O / W (solid-in-oil-in-water) process which needs to prepare the drug microparticles in advance, that drug release fails to occur in an early stage while rapid drug release happens in a late stage are overcome; and moreover, the sustained-release microparticles are relatively high in drug loading ratio and drug entrapment efficiency.

The invention relates to a method that a functional drug is enveloped into a polymeric material with biodegradability to form a nano-micron microsphere system. The method comprises that the polymeric material and simvastatin are dissolved in an organic liquor to form uniform dispersion which is then added into an liquor containing emulsifier Tween 80 and biologically nontoxic electrolytic polyvinyl alcohol or sodium dodecyl benzene sulfonate (SDBS), and then the obtained liquor is stirred, evaporated at a reduced pressure, centrifugalized, washed and vacuum dried, finally the simvastatin-contained delayed-release microsphere system is obtained. The surface of the microsphere is smooth and round, the granule thereof is regular without conglutination, and the granule diameter, the drug-loading rate (1-10 percent) and the encapsulation rate (above 40 percent) are all controllable, and the delayed-release time exceeds 2 months. The prepared simvastatin-contained delayed-release microsphere system can be processed into various preparations used in bony tissue absorption or bony defect parts, the microsphere system is degraded at a proper speed, thus the simvastatin can be further released; the degradation of the polymer can provide bony tissue with subsequent recuperating space to complete the repair of the bony defect parts.

A polypeptide-medicine-slow-releasing microsphere preparation. The preparation method for the preparation comprises the steps: dissolving a polylactic acid-glycolic acid polymer or a polylactic acid together with a protective agent and polypeptide medicine in an organic solvent to form a uniform mixed solution; adding the mixed solution to an oil phase to form an emulsion; removing the organic solvent, centrifuging, washing, and freezing and drying to obtain the polypeptide-medicine-slow-releasing microspheres. By using the 0 / 0 method, outward diffusion of the medicine into water phase is eliminated, and the medicine embedding rate is raised to 60% to 95%. The release time for a bioactive polypeptide medicine can last several weeks to several months, and in vitro release approximately matches zero-order release.

The invention relates to cubic liquid crystal in-situ gel injection of local anesthetic, and a preparation method of the injection. The injection is prepared from the local anesthetic, a liquid crystal material and an organic solvent and / or a release regulator; the local anesthetic is amide local anesthetic and the mass concentration of the local anesthetic is 0.1 to 8 w / w%; the organic solvent is an organic solvent which is mutually soluble with water, the liquid crystal material is mono-oleic acid glycerolipid, and the mass ratio of the liquid crystal material to the organic solvent is (1-9):1; and the release regulator is selected from at least one of medium chain triglyceride, oleic acid, tocopherol and tocopheryl acetate, and the mass concentration of the release regulator is 0 to 30 w / w%. The cubic liquid crystal in-situ gel injection of the local anesthetic has very good long-acting sustained release effect, low sudden release raten high compliance and small adverse effect, can reduce administration times and can avoid the peak valley phenomenon.

The invention discloses a preparation method of sustained-release microparticles, which comprises the following steps: 1) preparing a solid dispersion of water-soluble medicine and a biodegradable and biocompatible poorly water-soluble polymer; 2) preparing the prepared solid dispersion Dissolve in organic solvent C to form a solid dispersion emulsion; 3) inject the obtained solid dispersion emulsion into an oil solution containing a surfactant to form a uniform emulsion; 4) solidify the particles in the emulsion by solvent volatilization or solvent extraction , collecting microparticles, washing and drying to obtain the sustained-release microparticles; the present invention also discloses the sustained-release microparticles prepared by the preparation method of the sustained-release microparticles and the application of the sustained-release microparticles in implantable sustained-release pharmaceutical compositions . The preparation method of the sustained-release microparticles of the present invention is at normal temperature or low temperature throughout the process, which is very beneficial for the preparation of polymer matrix compositions for high-temperature sensitive drugs; at the same time, the prepared sustained-release microparticles have an excellent sustained-release effect close to zero order, and the drug concentration is between Stable during sustained release.