11results about How to "Avoid sudden release" patented technology

The invention relates to the technical field of bactericides, and discloses an oilfield flooding bactericide containing plant bactericidal components and a preparation method thereof. The preparation method comprises the following steps: loading the plant-based traditional Chinese medicine extract and the isothiazolinone-based corrosion inhibitor on the silver-loaded cyclodextrin metal organic framework to prepare an antibacterial agent / silver-loaded cyclodextrin metal organic framework composite material, and mixing the antibacterial agent / silver-loaded cyclodextrin metal organic framework composite material with methyl methacrylate to prepare the antibacterial agent / silver-loaded cyclodextrin metal organic framework composite material. The bactericide obtained by carrying out copolymerization reaction on modified hydroxyquinoline, vinyl quaternary phosphonium salt and methacrylic acid through an in-situ polymerization method can effectively kill and inhibit the breeding of sulfate reducing bacteria and other bacteria in oilfield reinjection water, and has a certain corrosion inhibition effect.

The invention relates to the technical field of chemical pharmacy, in particular to a preparation method and application of troxerutin, and hydroxyethylation reaction is carried out on phenolic hydroxyl groups on a rutin flavone skeleton. Specific two-stage reaction is adjusted, and catalysts sodium hydroxide and sodium methoxide are selected in the first stage; in the second stage, the pH value is adjusted, and the high-purity and high-yield troxerutin is prepared under certain conditions by adopting a catalyst with a specific combination and a specific ratio, the purity can reach 99% or above after simple purification, and the yield reaches 93% or above. Furthermore, the invention also relates to an orally disintegrating tablet and a multi-layer slow-release dressing.

This application provides a composite wound dressing and its preparation method, belonging to the field of medical dressing technology. The composite wound dressing includes an outer support layer and an inner functional layer. The outer support layer is a modified ramie fiber nonwoven fabric, the modification including low-temperature plasma treatment and acetylation modification of the ramie fibers. The inner functional layer is a composite of ramie woven fabric and low-antigen collagen sponge grafted with carvacrol. The collagen sponge penetrates the yarn gaps and pores of the woven fabric, forming a structure in which the collagen sponge and ramie fibers mutually wrap and interweave. The dual-layer structure design of the dressing, with its outer support layer and inner functional layer, provides stable mechanical support through the outer layer to maintain the dressing's shape, while the inner layer enables efficient absorption of exudate and sustained release of antibacterial components, actively promoting wound healing. It exhibits excellent biocompatibility and low immunogenicity risk.

The invention provides a preparation method of a drug carrier of paclitaxel nanoparticles wrapped in bacterial outer membrane vesicles, the preparation method comprising the following steps: (1) preparing outer membrane vesicles of Helicobacter pylori mutant strain QS003 (Helicobacteri pyloriΔfutBΔlpxEΔlpxFΔsncRNA‑2509025ΔtolB with plasmid Hbp+AffiHER2‑AffiEGFR1‑AffiVEGF); (2) mixing the obtained outer membrane vesicles with polylactic acid nanoparticles loaded with paclitaxel and mechanically extruding them to prepare outer membrane vesicles wrapped in paclitaxel nanoparticles. The drug carrier of paclitaxel nanoparticles wrapped in bacterial outer membrane vesicles obtained by the invention can well avoid the sudden release of the drug, the release ratio within 2 hours in the gastric fluid environment is less than 11%, the damage of gastric acid can be prevented, the degree of drug release in the stomach is reduced, and the drug utilization is improved.

This invention belongs to the field of biomedical materials and relates to a method for preparing a multi-dynamically bonded hydrogel based on polysaccharides from the traditional Chinese medicine *Solanum nigrum* and its application. *Solanum nigrum* is initially extracted and precipitated with alcohol to obtain crude polysaccharides. The polysaccharides are then deproteinized using the Sevag method to obtain a crude polysaccharide solution. After dialysis and freeze-drying, crude polysaccharide is obtained. The crude product is separated and purified to obtain homogeneous polysaccharides. The homogeneous polysaccharide solution is reacted with sodium periodate solution in the dark, followed by dialysis, purification, and freeze-drying to obtain oxidized *Solanum nigrum* polysaccharide OBY. OBY is dissolved in boric acid solution to obtain solution A. Carboxymethyl chitosan is dissolved in polyvinyl alcohol solution to obtain solution B. After the solutions A and B have fully reacted, they are placed in a mold to obtain a multi-dynamically bonded hydrogel based on *Solanum nigrum* polysaccharides. This hydrogel can be applied to the preparation of drugs for chronic wound repair, providing a novel material system and application strategy for developing new wound dressings with excellent physicochemical properties, intelligent response characteristics, and active repair functions.

The present invention belongs to the technical field of pharmaceutical preparations, and specifically relates to a gel sustained-release preparation with a sparingly soluble salt as a pH regulator, and a preparation method and application thereof. The gel sustained-release preparation with a sparingly soluble salt as a pH regulator is obtained by blending sparingly soluble salt crystalline powder, alkaline coatings and polymer solutions. This type of preparation is injectable and can be converted into a gel state after being injected into the body, so as to achieve the slow release of the coating at the injection site. The sparingly soluble salt reduces the solubility of the coating in the gel by adjusting the pH inside the gel, so that part of the coating is dispersed in the gel network in the form of crystals. In the early stage, the sudden release of the coating from the gel is prevented, and in the later stage, as the acidic degradation products of the gel accumulate, the sparingly soluble salt gradually dissolves, thereby achieving the sustained release of the coating. This technology can be applied to the fields of long-acting analgesia, medical cosmetology and anti-tumor.

The invention provides propranolol temperature-sensitive hydrogel as well as a preparation method and application thereof, and belongs to the technical field of medicines. The propranolol temperature-sensitive hydrogel disclosed by the invention is prepared from chitosan-beta-sodium glycerophosphate hydrogel and nano microspheres loaded on the chitosan-beta-sodium glycerophosphate hydrogel, wherein the chitosan-beta-sodium glycerophosphate hydrogel is a chitosan-beta-sodium glycerophosphate hydrogel; the nano microspheres are chitosan microspheres which are used for encapsulating propranolol; the mass of the nano microspheres is 1%-20% of the mass of the chitosan-beta-sodium glycerophosphate hydrogel. The propranolol temperature-sensitive hydrogel provided by the invention is a dual slow-release temperature-sensitive hydrogel system, not only has remarkable controlled release performance, can release drugs more continuously and stably, but also has good drug loading property and stable rheological property.

The invention discloses empagliflozin and metformin compound sustained-release granules and a preparation method thereof.The empagliflozin and metformin compound sustained-release granules comprise empagliflozin quick-release granules and metformin sustained-release coating granules, each metformin sustained-release coating granule comprises a core layer and a coating layer, the core layer is a mixture of metformin hydrochloride, an adhesive and sodium polystyrene sulfonate, and the coating layer is a mixture of metformin hydrochloride, an adhesive and sodium polystyrene sulfonate. The sodium polystyrenesulfonate accounts for 10%-30% of the total weight of the metformin sustained-release coated granules; the coating layer is a mixed material of polyvinyl acetate, triacetin and Tween 80, and the mass ratio of polyvinyl acetate to triacetin to Tween 80 is (75-85): (10-15): (5-10). Sodium polystyrenesulfonate and metformin hydrochloride are mixed and then coated with the coating layer, so that the bitter taste of metformin hydrochloride can be completely covered.

This invention discloses a pH-responsive nanodiamond drug delivery system and its preparation method, belonging to the field of nanomedicine carrier technology. The delivery system uses polyglycerol-modified nanodiamond (NDPG) as the base carrier, covalently loading doxorubicin (DOX) via pH-sensitive hydrazone bonds, and combining it with hyaluronic acid (HA) to achieve targeted modification and surface-stabilized coating, ultimately forming an HA-DOX / NDPG composite system or an NDPG-DOX@HA core-shell structure. The preparation method includes: in-situ ring-opening polymerization grafting of polyglycerol onto the nanodiamond surface to obtain NDPG; activation of hyaluronic acid followed by coupling with adipic acid dihydrazide, then forming hydrazone bonds with doxorubicin to obtain HA-DOX; activation of NDPG followed by grafting of connecting arms, then coupling with doxorubicin to obtain NDPG-DOX, and finally coating with hyaluronic acid to obtain the core-shell product. The carrier of this invention exhibits good water dispersibility, stable drug loading rate, low drug leakage under physiological conditions, rapid drug release in the weakly acidic environment of tumors, and also possesses active targeting capability and good biocompatibility. It can be used to prepare highly effective and low-toxicity antitumor drugs, and has high clinical application and translational value.

The application provides a kind of pneumatic monorail crane brake spring assembly and pneumatic monorail crane brake device, including first spring seat assembly, second spring seat assembly, brake spring, compression release mechanism and guide mechanism;First spring seat assembly and second spring seat assembly are oppositely arranged along brake spring axial direction, and brake spring is arranged between the two pressing plates;Compression release mechanism includes a plurality of pull rods threaded through the two pressing plates and nuts threaded with the pull rods, and the distance between the two pressing plates is changed and limited by adjusting the position of the nuts;Guide mechanism includes positioning guide cylinder and positioning guide rod inserted therein, for guiding the axial relative movement of the two spring seat assemblies.The assembly can be installed as a whole to the brake part or removed from the brake part, reducing the difficulty of brake spring assembly and maintenance;The cooperation of pull rod and nut can realize spring compression, release and locking, reduce the risk of sudden release;The cooperation of guide cylinder and guide rod can limit the bending deformation of spring, improve the stress state and prolong the service life.

This invention relates to the field of medical technology, specifically to an injectable antioxidant hydrogel adapted to the mechanical properties of the nucleus pulposus, its preparation method, and its applications. The hydrogel uses a polypeptide-polymer copolymer as its backbone, and by adjusting the polymer network structure to match the mechanical properties of the nucleus pulposus, it achieves synergistic optimization of antioxidant properties, mechanical support, and biocompatibility. Because it does not rely on any drug bioactive factors, it can also effectively solve the problems of burst release and over-release of loaded drugs, exhibiting excellent overall performance and possessing broad market application potential.